Tanta University Faculty of Agriculture Plant protection BIOLOGICAL AND CHEMICAL CONTROL FOR SOME PESTS OF AGRICULTURAL CROPS AND ITS SIDE EFFECTS. By Sabry AbdEl-Monem Abd-ElAal Abd-AllAh. B.Sc. Agric., (Pesticides), Tanta Univ., 1991. M.Sc. Agric., (Pesticides ), Tanta Univ., 1998. Thesis Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Supervision's Committee 1-Prof. Dr. Tsamoh Khatab Abd El-Raof Emeritus Prof. of Pesticides, Faculty of Agric. Tanta University. 2-Prof. Dr. Helmy Aly Ibrahim Anber Prof. of Pesticides, and Dean of the Faculty of Agric. Tanta University. 3- Prof. Dr. Abd-ElRahim. S. Metwally Head of Field Crops Pests Department, Plant Protection Research Institute, Agric. Research Center, Cairo, Egypt. 4- Dr. El-Sayed A. Kishk Lecturer of Pesticides. Faculty of Agriculture, Tanta University. (2008)
197
Embed
Sabry AbdEl-Monem Abd-ElAal Abd-AllAh(2008) PHD Thesis English
This is my PHD. My name:Sabry AbdEl-Monem Abd-El-Aal Abd-Allah The title: BIOLOGICAL AND CHEMICAL CONTROL FOR SOME PESTS OF AGRICULTURAL CROPS AND ITS SIDE EFFECTS. Abstract Series of field and laboratory experiments had been carried out in Faculty of Agriculture, Tanta University, for determination the efficiency of some substitute implement as a part of integrated pest management for European Corn Borer Ostrinia nubilalis (Hb.). The results obtained can be summarized as follows: The toxicity of the Biofly to the aphid species and red spider mite using leaf disk dipping technique could be arranged descendingly as follows: Tetranychus cinnabarinus > Rhopalosiphum maidis > Aphis craccivora > Aphis gossypii. While, the toxicity of the different oils against spider mite T. cinnabarinus using leaf-disc dipping technique could be arranged descendingly as follows: corn oil> cotton oil caster oil mineral oil>canola oil> paraffin oil. Most tested mixtures of corn and cotton oils with Beauveria bassiana (Biofly) were less toxic than the Biofly formulation. while, the mixtures which consists of 3 parts of Biofly and 1 part caster oil or canola or mineral and paraffin oils more toxic than Biofly formulation against T. cinnabarinus. All tested photostablizers and pigments mixtures with Biofly had increased the mixtures' toxicity to T. cinnabarinus mites. But when increasing the concentration ratio to 1% the toxicity decrease. Mixtures of Biofly + 0.1% acetophenon or 4-nitro acetophenon or 7-nitophenol or benzophenon, Biofly + 0.1% or 0.2% or 0.5%congo red and Biofly + 0.1% or 0.2% or 0.5% titan yellow mixtures had increased the toxicity of the Biofly formulation against adult T. cinnabarinus. The most persistence mixtures were 3Biofly:1paraffin oil, 3Biofly:1 castor oil, and Biofly+0.1% benzophenon, or +0.5% congo red or +0.1% 7-nitrophenol. Cultivars S.C.13 and T.W.C. 351 were the most tolerant cultivars against ECB infestation while, T.W.C.323 and 324 cultivars were the most susceptible cultivers. There are a positive relationship between %grain protein and the %damaged grain. The most potent insecticides against ECB infestation were diazinon and fenpropathrin but methomyl was the least toxic one. Diazinon followed by chlorpyrifos insecticides had the highest values in 100grain weight and grain yield/10plants. Spraying with diazinon, mixture No.4 [150ml Biofly + 50ml paraffin oil+ 0.1% benzophenon(0.2gm)+ 500ml diazinon] and mixture No.3 [(375gm Agrine + 125ml paraffin oil+ 0.1% benzophenon(0.5gm) + 500ml diazinon] had been reduced holes No./100internodes and cavities No./10plants. Diazinon, mixture No.4 and mixture No.3 had increase both 100 grain weight and grain yield/10plants Agerin (a Bacillus thuringiensis formulation), Agerin mixtures with oil or/with benzophenon and paraffin oil had no toxicity against adults of predator, Paederus alfierii. The toxicity of the rest biochemicals could be arranged descendingly as follows: mixture No.4 > mixture No.3 > diazinon. While mixture No.2 [150ml Biofly + 50ml paraffin oil+ 0.1% benzophenon(0.2gm)] were more toxic than Biofly.
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Tanta UniversityFaculty of Agriculture Plant protection
BIOLOGICAL AND CHEMICAL CONTROL FOR SOME PESTS OF AGRICULTURAL CROPS AND ITS
ThesisSubmitted in partial fulfillment of the requirements for the degree of Doctor
of PhilosophySupervision's Committee1-Prof. Dr. Tsamoh Khatab Abd El-RaofEmeritus Prof. of Pesticides, Faculty of Agric. Tanta University.
2-Prof. Dr. Helmy Aly Ibrahim AnberProf. of Pesticides, and Dean of the Faculty of Agric. Tanta University.
3- Prof. Dr. Abd-ElRahim. S. Metwally Head of Field Crops Pests Department, Plant Protection Research Institute, Agric. Research Center, Cairo, Egypt.
4- Dr. El-Sayed A. KishkLecturer of Pesticides. Faculty of Agriculture, Tanta University.
Date:30/7/2008
Head of Department Vice Dean for hight studies and researchers
Prof. Dr. Ibrahim I. Mesbah Prof. Dr. Ibrahim I. Mesbah
Tanta UniversityFaculty of Agriculture
Plant protection
BIOLOGICAL AND CHEMICAL CONTROL FOR SOME PESTS OF AGRICULTURAL CROPS AND ITS
SIDE EFFECTS.
Presented by
Sabry AbdEl-Monem Abd-El-Aal Abd-AllAhFor the degree of
Doctor of Philosophy in Agriculture Sciences (pesticides).
Examiners committee Approved by1-Prof. Dr. Tsamoh Khatab Abd El-Raof.Emeritus Prof. of Pesticides, Faculty of Agric, Tanta University.
------------------------------
2-Prof. Dr. Attiah Youssef KeratumProf. of Pesticides chemistry, Kafer El-Sheikh University
------------------------------
3- Prof. Dr. Helmy Aly Ibrahim Anber.Prof. of Pesticides, and Dean of the Faculty of Agric. Tanta University.
------------------------------
4- Prof. Dr. Ibrahim I. Mesbah.Prof. of Economic entomology, Head of the Plant Protection Dept. and Vice Dean of Faculty of Agric., Tanta University.
-----------------------------
Date 30 / 7 /2008
Name:Sabry AbdEl-Monem Abd-El-Aal Abd-AllahTitle: BIOLOGICAL AND CHEMICAL CONTROL FOR SOME PESTS OF
AGRICULTURAL CROPS AND ITS SIDE EFFECTS.Degree:Doctor of Philosophy in Agriculture Sciences (pesticides) Plant
production Departments, Faculty of Agricultural, Tanta University.Abstract
Series of field and laboratory experiments had been carried out in Faculty of Agriculture, Tanta University, for determination the efficiency of some substitute implement as a part of integrated pest management for European Corn Borer Ostrinia nubilalis (Hb.). The results obtained can be summarized as follows:
● The toxicity of the Biofly to the aphid species and red spider mite using leaf disk dipping technique could be arranged descendingly as follows: Tetranychus cinnabarinus > Rhopalosiphum maidis > Aphis craccivora > Aphis gossypii. While, the toxicity of the different oils against spider mite T. cinnabarinus using leaf-disc dipping technique could be arranged descendingly as follows: corn oil> cotton oil >caster oil > mineral oil>canola oil> paraffin oil.
● Most tested mixtures of corn and cotton oils with Beauveria bassiana (Biofly) were less toxic than the Biofly formulation. while, the mixtures which consists of 3 parts of Biofly and 1 part caster oil or canola or mineral and paraffin oils more toxic than Biofly formulation against T. cinnabarinus. All tested photostablizers and pigments mixtures with Biofly had increased the mixtures' toxicity to T. cinnabarinus mites. But when increasing the concentration ratio to 1% the toxicity decrease. Mixtures of Biofly + 0.1% acetophenon or 4-nitro acetophenon or 7-nitophenol or benzophenon, Biofly + 0.1% or 0.2% or 0.5%congo red and Biofly + 0.1% or 0.2% or 0.5% titan yellow mixtures had increased the toxicity of the Biofly formulation against adult T. cinnabarinus.
● The most persistence mixtures were 3Biofly:1paraffin oil, 3Biofly:1 castor oil, and Biofly+0.1% benzophenon, or +0.5% congo red or +0.1% 7-nitrophenol.
● Cultivars S.C.13 and T.W.C. 351 were the most tolerant cultivars against ECB infestation while, T.W.C.323 and 324 cultivars were the most susceptible cultivers. There are a positive relationship between %grain protein and the %damaged grain.
● The most potent insecticides against ECB infestation were diazinon and fenpropathrin but methomyl was the least toxic one. Diazinon followed by chlorpyrifos insecticides had the highest values in 100grain weight and grain yield/10plants.
● Spraying with diazinon, mixture No.4 [150ml Biofly + 50ml paraffin oil+ 0.1% benzophenon(0.2gm)+ 500ml diazinon] and mixture No.3 [(375gm Agrine + 125ml paraffin oil+ 0.1% benzophenon(0.5gm) + 500ml diazinon] had been reduced holes No./100internodes and cavities No./10plants. Diazinon, mixture No.4 and mixture No.3 had increase both 100 grain weight and grain yield/10plants
● Agerin (a Bacillus thuringiensis formulation), Agerin mixtures with oil or/with benzophenon and paraffin oil had no toxicity against adults of predator, Paederus alfierii. The toxicity of the rest biochemicals could be arranged descendingly as follows: mixture No.4 > mixture No.3 > diazinon. While mixture No.2 [150ml Biofly + 50ml paraffin oil+ 0.1% benzophenon(0.2gm)] were more toxic than Biofly.
CONTENTS CONTENTS LIST OF TABLES..........................................................................................V
LIST OF FIGURES......................................................................................IX
V - SUMMARY...........................................................................................147
VI - REFERENCES....................................................................................151
List of TablesList of TablesTable III.1: Some physical and chemical characters of the experiment soils.63
Table III.2: The monthly average of temperature and relative humidity during 2003 season in both locations.......................................................63
Table III.3: The mixtures used in the field experiments and their application rates ..............................................................................................66
Table III.4: The monthly average temperatures and relative humidity during the two growing seasons 2004 and 2005.....................................66
Table IV.1: Toxicity of Beauveria bassiana against some aphid species and two-spotted spider mite Tetranychus cinnabarinus by using slide dipping and leaf-disc dipping technique respectively...................73
Table IV.2: Toxicity of some botanical oils and mineral oil against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique..........................................................................77
Table IV.3: The toxicity of Biofly mixtures with different oils by the ratio (1:3 v/v) on two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique................................................81
Table IV.4: The toxicity of Biofly mixtures with different oils by the ratio (1:2 v/v) on two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique................................................82
Table IV.5: The toxicity of Biofly mixtures with different oils by the ratio (1:1 v/v) on two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique................................................83
Table IV.6: The toxicity of Biofly mixtures with different oils by the ratio (2:1 v/v) on two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique................................................84
Table IV.7: The toxicity of Biofly mixtures with different oils by the ratio (3:1 v/v) on two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique................................................85
Table IV.8: Toxicity of the Biofly mixtures with the acetophenone (photostabilizer) against two-spotted spider mite Tetranychus
VI List of Tables
cinnabarinus by using leaf disk dipping technique.....................88
Table IV.9: Toxicity of the Biofly mixtures with the 4-nitro acetophenon (photostabilizer) against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.....................89
Table IV.10: Toxicity of the Biofly mixtures with the 7-nitophenol (photostabilizer) against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.....................90
Table IV.11: Toxicity of the Biofly mixtures with the benzophenon (photostabilizer) against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.....................91
Table IV.12: Toxicity of the Biofly mixtures with the titan yellow pigment against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique................................................92
Table IV.13: Toxicity of the Biofly mixtures with the congo red pigment against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique................................................93
Table IV.14: The effect of exposure to UV radiation interval on the efficiency of Beauveria bassiana mixtures with botanical and mineral oils against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique................................................94
Table IV.15: The effect of exposure to UV radiation interval on the efficiency of Beauveria bassiana mixtures with some photostabilizers against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique................................................95
Table IV.16: Susceptibility of ten corn cultivars to infestation with ECB in El-Gharbia and El-Behira governorates under natural infestation conditions(2003 season). .............................................................99
Table IV.17: 100 grain weight, grains yield and grains yield reduction as a result of natural infestation with ECB on ten corn cultivars at El-Gharbia and El-Behira governorates..........................................100
VII List of Tables
Table IV.18: Efficiency of four chemical insecticides against ECB infestation on ten corn cultivars evaluated by holes number/100 internodes in the two locations.........................................................................116
Table IV.19: Efficiency of four chemical insecticides against ECB infestation on ten corn cultivars evaluated by cavity number/10plants in the two locations...............................................................................117
Table IV.20: Efficiency of four chemical insecticides against ECB infestation on ten corn cultivars evaluated by larvae number/10plants in the two locations...............................................................................118
Table IV.21: Efficiency of four chemical insecticides against ECB infestation on ten corn cultivars evaluated by holes number/10 ear stalks in the two locations.........................................................................119
Table IV.22: Efficiency of four chemical insecticides against ECB infestation on ten corn cultivars evaluated by damage grains% in two locations......................................................................................120
Table IV.23: Effect of chemical insecticides treatments and corn cultivars on grains protein percentage............................................................121
Table IV.24: Effect of chemical insecticides treatments and corn cultivars on grains phosphors percentage.......................................................122
Table IV.25: Effect of chemical insecticides treatments and corn cultivars on 100 grains weight (g.).................................................................123
Table IV.26: Effect of chemical insecticides treatments and corn cultivars on grains yield/10plants (kg.)..........................................................124
Table IV.27: Some chemical and physical parameters of ten corn cultivars. 126
Table IV.28: Efficiency of biocides treatments against ECB infestation on three corn cultivars evaluated by holes number/100 internodes, during 2004 and 2005 seasons....................................................139
Table IV.29: Efficiency of biocides treatments against ECB infestation on three corn cultivars evaluated by cavity number/10 plants, during
VIII List of Tables
2004 and 2005 seasons...............................................................140
Table IV.30: Efficiency of biocides treatments against ECB infestation on three corn cultivars evaluated by larvae No./10 plants, during 2004 and 2005 seasons...............................................................141
Table IV.31: Effect of biocides treatments and corn cultivars on 100 grain weight(g.), during 2004 and 2005 seasons.................................142
Table IV.32: Effect of biocides treatments and corn cultivars on grains yield/10plants (kg.), during 2004 and 2005 seasons ..................143
Table IV.33: Toxicity of biochemicals against adults of the predator, P. alfierii exposed to surface deposit technique.........................................146
List of figuresList of figuresFig IV.1: Probit regression lines for the toxicity of Biofly to some Aphis spp
and two-spotted spider mite Tetranychus cinnabarinus. ..................74Fig IV.2: Probit regression lines for the toxicity of some botanical oils and
mineral oil to two-spotted spider mite Tetranychus cinnabarinus. . .78
ACKNOWLEDGMENTACKNOWLEDGMENT
I strongly owe my thanks to ALLAH for lighting me the way and
directing me across every success.
The author wishes to express his deep thanks to Prof. Dr. Tsamoh
Khatab Abd El-Raof Professor of Pesticides, Plant Protection Department,
Faculty of Agriculture, Tanta University, for suggesting the problem and her
supervision during the course of these studies and during revision of the
manuscript.
Sincere thanks, appreciation and deep gratitude to Prof. Dr. Helmy
Aly Ibrahim Anber Prof. of pesticides, and Dean of the Faculty of
Agriculture, Tanta University, for his supervising in my committee and for his
continuous support through the period of study.
Deepest and sincere gratitude to Dr. Abd-ElRhim. S. Metwally Head
of Field Crop Pests Department, Plant Protection Research Institute, Agric.
Research Center, Cairo, Egypt for supervising the work, efforts in revising
the manuscript and discussing data, providing technical help and valuable
scientific assistance.
The author wishes also to thank Dr. EL-Sayed A. Kishk Lecturer of
Pesticides. Faculty of Agriculture, Tanta University, for his valuable
supervision, scientific suggestions, guidance, and kind help during the period
of the work .
I wish to express my deep gratitude to Prof. Dr. Ibrahim I. Mesbah
Chairman of the plant protection Department and Vice Dean of Faculty of
Agriculture, Tanta University, for his kind help and advice through this study.
Deep thank are also to all members in pesticides Department Faculty
of Agriculture, Tanta University, for their continuous encouragement and
offering all facilities through out this work.
I - I - INTRODUCTIONINTRODUCTIONCorn (Zea mays L.) is one of the most important grains crops in Egypt.
The amount of corn needs is far greater than that produced locally. To
overcome this problem and increase production under limited arable lands in
Egypt, it may be through cultivate corn in the early season (in the beginning
of March) and in the late season (in the beginning of July) as well. But,
European corn borer (ECB) Ostrinia nubilials (Lepidoptera: Pyraustidae)
infestation increases in the late season and become a limiting factor to
increase the corn production, it causes a stalk damage that results in great
grains yield reductions reached to 45 % (Lutfalla and Sherif 1992).
Over use of insecticides led to increase problems of pest resistance,
destruction of beneficial insects or non-target organisms, insecticides residues
and human hazards.
The increased public awareness and concern for environmental safety
has directed research to the development of alternative control strategies such
as the use of microbial control agents for controlling ECB by using Beauveria
bassina and Bacillus thuringiensis formulations.
One of the major challenges to use the microbial biopesticides is their
lack of persistence in the field due to environmental factors such as sunlight,
high temperature, and water stress. Sunlight particularly UVB (280-320 nm
portion) is likely the most destructive of these environmental factors by the
direct structural effects on DNA or indirect damage caused by the formation
of reactive oxygen molecules (Ignoffo and Garcia, 1978, 1994; Ignoffo,
1992). The half- life of most entomopathogenic fungal conidia ranges from 1
to 4 hr in stimulated sunlight and 4 to 400 hours in natural sunlight on foliage.
Many researchers have screened many additives materials to protect
bioinsecticides from degradation by sunlight. A number of laboratory and
2 INTRODUCTION
field studies indicates that oil formulations and photo-protective agents
improve the efficacy of entomopathogenic formulations (Inglis et al. 2002;
Moore et al 1993 and Alves et al 1998).
So, the goal of this study is to achieve an integrated biocontrol for the
European Corn Borer(ECB) especially in late season through the following:
1- Enhanced the persistence of bioinsecticides formulations against
UV radiations by mixing them with some botanical oils, mineral oils, some
photostablizer compounds and some pigments.
2- Selection of the most tolerant commercial corn cultivars to use as a
major key of integrated pest management of ECB infestation.
3- Choose the most potent insecticides of the common insecticides
used to control ECB in the late season.
4- Finally, use the mixtures of enhanced bioagents with the most
effective insecticides (in a minimum concentration) and the most tolerant
commercial corn cultivators to obtain the most effective biochemical control
of ECB infestation under the field conditions.
II - II - REVIEW OF LITERATUREREVIEW OF LITERATURE
II.1 Pesticides efficiency against the European corn borer (ECB) Ostrinia nubilalis (Hubner).
Barbulescu (1971), stated that endosulfan (Thiodan), diazinon
(Basudin), bromophos, carbaryl (Sevon) and disulfoton (Solvirex) gave very
good results in controlling the Ostrinia nubilalis (Hb.) larvae, while those
afforded by trichlorphon (Dipterex) were less satisfactory. No significant
differences in the effectiveness of the compounds were observed between the
different hybrids.
Berry et al. (1972), found that granules of diazinon at 1 libra (lb)
toxicant/acre, Velsicol VCS-506 at 1.5 lb, carbofuran at 0.5 lb, Pennwalt
TD-5032 (hexamethylditin) at 0.75 lb, monocrotophos at 0.75 lb and DDT at
1 lb and sprays of DDD (TDE) at 1.5 lb, Bay 79845 at 1 lb, carbofuran at 1 lb,
Chevron 9006 at 1 lb and DDT at 1 lb were the most effective against the
first generation of ECB larvae. On the other hand, granules of Pennwalt
TD-5032 at 0.75 lb, carbofuran at 1 lb and Velsicol VCS-506 at 1.5 lb and
sprays of Bay 79845 at 1 lb, carbofuran at 1 lb and Bay 93820 at 1 lb were
the most effective against the second-generation larvae of Ostrinia nubilalis .
Hills et al. (1972), studied the effect of insecticide applications timing
for controlling larvae of Diabrotica virgifera Lec. and first generation larvae
of Ostrinia nubilalis (Hb.) on maize. They found that, the most effective
control of Ostrinia was given by the post-sowing treatments applied on 2nd
July. The timing of applications was particularly critical with diazinon,
which was about the most effective material, but not so critical with Dyfonate,
fensulfothion or carbofuran, which also gave good results.
4 REVIEW OF LITERATURE
McClanahan and Founk (1972), reported that in laboratory tests
parathion was the most effective ovicide against Ostrinia nubilalis (Hb.).
The larvae were more susceptible than the eggs. In 1970 and 1971, heavy
populations of the multivoltine strain of O. nubilalis were controlled on sweet
maize and peppers [Capsicum] by twice-weekly sprays of carbaryl, methomyl
(Lannate) and Phosvel. Carbofuran (Furadan) applied weekly provided good
control, and several experimental compounds were effective.
Gerginov (1973), investigated the effectiveness of some chemical
preparations for the control of the maize stem borer Ostrinia (Pyrausta)
nubilalis (Hb.). He found that, the best results were achieved with 5%
endosulfan (Thiodan), 5% diazinon and 5% bromophos (Nexion) applied in
granules manually at 1 g/plant, which gave 92.25, 81.79 and 77.91% mortality
of first generation larvae and increased the yield by 833, 617 and 653 kg/ha,
respectively. Also with two applications of 5% endosulfan at 0.5 g/plant,
larval mortality was 96.8%. While it was 92.7% with one application of
endosulfan in granules followed by a wettable powder spray of the same
toxicant.
Melia Masia and Almajano Contreras (1973), applied granular
formulations containing 3% phosmet (Imidan), 2.5% diazinon or 5%
monocrotophos at rates of 25, 25 and 20 kg/ha, respectively, to the upper part
of the maize plants on 12th, 14th July, 2- 4 days after the adults flight peak.
They showed that there were no significant differences between the
treatments, on average yield, the populations of Ostrinia had been reduced
by 82.4% as compared with control.
Harrison (1974), investigated the chemical control of ear-infesting
5 REVIEW OF LITERATURE
insects of sweet corn Heliothis zea (Boddie), Ostrinia nubilalis(Hb.) and
Carpophilus lugubris Murr, in field tests and indicated that Dursban
(Lorsban) and leptophos were as effective as carbaryl.
Hudon and Castagner (1976), tested 13 insecticides in the field for
the control of a natural outbreak of Ostrinia nubilalis(Hb.) on maize. They
indicated that only chlorpyrifos (as Lorsban 10G) gave good results, with only
4% of ears attacked. Chlorpyrifos, triazophos (Hostathion 5G), FMC 33297
4EC, N 2596 10G and carbaryl 85W gave satisfactory results.
McWhorter et al. (1976), evaluated the effectiveness of the spray and
granular formulations of some insecticides (toxaphene, diazinon, carbaryl,
EPN, carbofuran and malathion) for the control of artificial infestations of the
Ostrinia nubilalis (Hb.) first generation on maize in field plot tests. They
made the infestations by placing egg-masses at the black-head stage on plants
at the mid-whorl stage at 2, 4, 6 and 8 days after treatment. They indicated
that, the granular formulations were effective for the entire eight day period,
whereas the spray formulations were less effective than the granules after five
days.
Mustea (1977), studied the effectiveness of several different
insecticides for the control of Ostrinia nubilalis (Hb.) in maize fields. He
found that the granules reduced attack by 58-71%, with a definite relationship
between the amount of insecticide applied and the numbers of damaged
plants. The best control of the borer was obtained with diazinon (Basudin),
carbofuran (Furadan) and kelevan (Despirol), all in 5% granules, whereas the
highest maize yields were obtained with 5% granules of chlorfenvinphos
(Birlane), carbofuran and gamma BHC (Lindatox) applied in two treatments
6 REVIEW OF LITERATURE
each at 1 kg toxicant/ha. The lower yields recorded for some compounds such
as diazinon, disulfoton (Disyston) and carbaryl (Sevin) were due to phytotoxic
effects of the compounds. He attributed the generally poor results of the most
insecticides to the long flight period of the pest, the late application of the
compounds and their loss of toxicity with time and weathering.
Straub (1977), studied the role of pre-silk applications and leaf
feeding resistance. He found that insecticide spray applications to silks alone
did not provide acceptable control. Multiple pre-silk applications were
unnecessary when methomyl at 0.5 kg/ha or encapsulated methyl-parathion at
0.6 kg were used; a single late-whorl application of either insecticide followed
by 3 silk sprays was sufficient. Carbaryl was ineffective. Use of B49XB68, a
leaf- feeding resistant dent genotype, coupled with 3 silk sprays of any tested
materials, provided a degree of control comparable to a full program (2 whorl
and 3 silk sprays) with the best insecticides on susceptible sweet maize.
Thompson and White (1977), carried out Field-plot tests to
determine the effectiveness of several insecticides applied in granules or as
sprays to whorls for the control of populations of Ostrinia nubilalis(Hb.) on
silage maize. They assumed that all treatments significantly reduced the
number of larval cavities/plant recorded at the harvest. Carbofuran, parathion,
diazinon, fonofos, permethrin (NRDC-143), WL 43775, N-2596 and
fensulfothion gave the best control. Silage yields were not significantly
affected by any of the treatments, despite excellent larval control. However, a
significant increase in the grain component of the silage was observed in 1974
from plots treated with carbofuran, parathion, carbaryl and diazinon.
Martel and Hudon (1978), stated that only chlorpyrifos and
7 REVIEW OF LITERATURE
permethrin of 14 insecticides laboratory tested against first instar larvae of
Ostrinia nubilalis(Hb.), were more effective than DDT and carbaryl.
Carbofuran and primidophos were only slightly less effective than DDT and
carbaryl. Also they showed that carbofuran, diazinon, fonofos, N-2596, and
chlorpyrifos were promising as granular treatments, but carbaryl was
ineffective in greenhouse tests with commercial formulations applied to maize
plants at the whorl stage.
Raemisch and Walgenbach (1983), evaluated the effectiveness of
emulsifiable concentrates of permethrin or cypermethrin and granular
formulations of fonofos, carbofuran, phorate or chlorpyrifos at various rates
for the control of 1st generation larvae of Ostrinia nubilalis(Hb.) on maize.
They found that all the treatments significantly reduced borer damage, as
measured by cavity counts within the stalk. The liquid treatments proved to be
as effective as the granular treatments when both were applied over the row.
Also they evaluated the impact of 1st generation larvae on silage yield in two
tests; they found that, in each case, dry-matter yield was reduced by such
infestations. The yield in untreated controls was 14.1 and 14.7% lower than in
cypermethrin treated plots with 0.11 kg a.i./ha.
Straub (1983), evaluated the effectiveness of granular whorl
treatments with several insecticides for the control of 1st generation larvae of
Ostrinia nubilalis(Hb.) on sweet maize fields. They showed that, when
infestation pressure was light to moderate, a single granular application
compared favourably with multiple foliar sprays of the standard treatment
(methomyl at 0.5 kg a.i./ha), but supplementary sprays were necessary under
heavy infestation pressure. Terbufos at 1.12-2.24 kg, and chlorpyrifos, fonofos
8 REVIEW OF LITERATURE
and isofenphos all at 1.12 kg were the best granular treatments. They
concluded that, use of granular whorl treatments could effectively reduces the
number of treatments and could fit well into pest management programmers
for sweet maize.
Khasan and D'Yachenko (1984), determined the effectiveness of the
insecticides diflubenzuron (Dimilin), parathion-methyl (metaphos) and
diazinon (Basudin), Lepidocide [ Bacillus thuringiensis var. kurstaki
formulation] and mixtures containing Lepidocide and parathion-methyl or
diazinon against the European corn borer Ostrinia nubilalis (Hb.) on maize.
They stated that, the most effective treatments were the mixtures of
Lepidocide at 2 liters/ha with either parathion-methyl at 0.15 litre/ha or
diazinon at 0.1 litre/ha.
Mestres and Cabanettes (1985), investigated the target and non target
effects of chemical control measures against the maize pyralid Ostrinia
nubilalis in about 60 trials throughout France in about 1980-84. They
reported that, a granular formulation of chlorpyrifos, (a reference compound)
afforded a mean efficacy of 77% against larvae in the ears and 82% against
those in the stems. Yields were only weakly correlated with the extent of
larval infestation, but the results of treatment were strongly correlated with
yields when yields exceeded 75 quintal(100kg)/hectare.
Molinari and Mazzoni (1986), fulfilled investigations to determine
the damage level caused by natural infestation of several maize hybrids by the
pyralid Ostrinia nubilalis (Hb.) and also the effectiveness of a deltplane for
application of insecticide for the control of the ECB. They assessed the level
of infestation by means of pheromone traps for the adults and visual counts of
9 REVIEW OF LITERATURE
egg masses, entrance holes and (at the harvest) mature larvae of the 2nd
generation. They assumed that yield losses were found to be significantly
correlated with the numbers of entrance holes and not with the numbers of
mature larvae; maize plants with 2-4 holes yielded 2.96% less and those with
5 or more holes yielded 14.8% less than uninfested plants. In control tests,
applied a preparation containing Bacillus thuringiensis subsp. kurstaki, by
deltaplane at 2.4×1010 International Unite/hectare (IU/ha) against the 2nd
generation only, and chlorpyrifos at 470 g/ha either once against the 2nd
generation alone or twice against the 1st and 2nd generations reduced the
infestation significantly.
Voinescu and Barbulescu (1986) tested the effectiveness of granules
of eight insecticides, each applied at 2 kg a.i./ha, on maize plants artificially
infested with Ostrinia nubilalis at higher rates than those likely to occur in
nature. They declared that, the best results (in terms of stalk cavity length,
number of larvae per plant, percentage of plants with cob damage, and grains
yield) were afforded by diazinon, chlormephos, chlorpyrifos, carbofuran and
profenofos.
Aguilar et al. (1987), determined the optimum timing for insecticides
applications to control the pyralid Ostrinia nubilalis and the noctuid Sesamia
nonagrioides in maize. They applied Ethyl chlorpyrifos to maize at 3 sites
as 17 applications throughout the crop growth period, 7 applications during
the 1st generations of the pests, 10 applications during the 2nd generations of
the pests and an untreated control. They found that, crops which applied with
insecticide against the 2nd generations of the pests contained significantly
lower numbers of borers and fallen plants than the untreated control. They
10 REVIEW OF LITERATURE
indicated that the 2nd generations of the maize borers are responsible for the
greatest damage in maize.
Felip et al. (1987), determined the efficacy and persistence of
nine insecticides, against the maize stem borers Ostrinia nubilalis and
Sesamia nonagrioides. They found that, the granular insecticides tended to be
less effective than liquid insecticides. Numbers of O. nubilalis larvae in
lindane and B. thuringiensis treatments and also numbers of both species in
these applications and methamidophos treatments were not lowered than those
in untreated controls. Grain yields and numbers of fallen plants were not
significantly different among treatments when compared with the untreated
control. The best control of O. nubilalis was achieved using chlorpyrifos
(granules and liquid), fenitrothion and trichlorfon liquid formulations and
granular permethrin.
Rinkleff et al. (1995), conducted field and laboratory studies using
selected carbamate, organophosphate and pyrethroid insecticides to quantify
their toxicity to Ostrinia nubilalis eggs and the residual mortality to neonate
larvae. They reported that, insecticides with the greatest ovicidal activity in
field trials, in decreasing order, included methomyl> encapsulated methyl
parathion> permethrin> thiodicarb> zeta-cypermethrin and lambda-
cyhalothrin. With the exception of methomyl, significant larval mortality was
also observed for each material. They conducted laboratory bioassays to
estimate the LC50 for insecticides showing the greatest ovicidal activity in the
field. Insecticides with the greatest ovicidal activity included, in decreasing
[thiram], monocrotophos and chlorpyrifos were found moderately tolerable to
the same fungus. Metarhizium anisopliae showed higher tolerance than B.
bassiana. However, both the pathogens were sensitive (70-100% growth
inhabitation) to carbendazim and baynate (thiophanate methyl) even at lower
concentrations (10 and 100 ppm). Nicast stimulated the growth of
Metarhizium anisopliae by 40-50% and no growth inhibition was observed in
B. bassiana. Sugar mill effluent was also found well tolerated by both the
fungi to the extent of 5% in Czapek's agar medium.
Xu, et al. (2002), showed that there are negative effects of the
pesticides on the germination of B. bassiana conidia increased with the
increasing pesticide concentrations. Two fungicides, chlorothalonil 75% WP
and mancozeb 70% WP, killed almost all the conidia of B. bassiana at all
concentrations. Five insecticides, including imidacloprid 10% WP, yashiling
22% WP (a mixture of imidacloprid and buprofezin), methomyl 20% EC,
triazophos 20% EC, and fipronil 5% FF, exhibited high compatibility with B.
bassiana conidia with germination rates exceeding 90% even at the highest
concentration. The other two insecticides, chlorfluazuron 5% EC and
fenvalerate 20% EC, greatly reduced the germination rate of B. bassiana at
the field-spray concentrations recommended, however, at lower
concentrations, the germination rates increased by a big margin. Abamectin
0.5% EC was highly incompatible with B. bassiana conidia at all the
concentrations tested.
Ashutosh, et al. (2005), assessed the compatibility between the
different rates of chemical pesticides and multineem [Azadirachta indica]
with Beauveria bassiana. Their treatments was comprised of : 0.05, 0.025
32 REVIEW OF LITERATURE
and 0.0125% endosulfan; 0.03, 0.0225 and 0.015% chloropyrefos 0.20, 0.15
and 0.10% mancozeb; 0.03 and 0.06 multineem and the control. They found
that, an increase in the concentration of the chemicals decreased the radial
growth of B. bassiana. However, the least toxic effect was mancozeb.
Multineem showed similar results.
II.3.1.d Effect of ultraviolet radiations (UV) on the Beauveria bassiana efficiency. Inglis, et al. (1995), determined the effect of ultraviolet light (UV)
protectants on the persistence of conidia of the entomopathogenic fungus
Beauveria bassiana. They found that, the survival of conidia applied in water
onto glass coverslips or crested wheatgrass (Agropyron cristatum) leaves was
reduced by >95% after 15 minute exposure to UV-B radiation. Substitution of
oil and water increased the survival of conidia on both substrates. However,
conidial survival in oil was more pronounced on glass (74% mortality after 60
min.) than on leaves (97% mortality after 60 min.). Also they found that, the
water-compatible the fluorescent brightener, Tinopal LPW and a clay
emulsion significantly increased the survival of conidia compared to the
water control, whereas Congo Red and the optical brightener, Blankophor
BSU, were ineffective. Conidial survival, in the field was not enhanced by
the 3 oil-compatible adjuvants tested (oxybenzone, octyl-salicylate and ethyl-
cinnamate). They concluded that, the use of UV-B protectants in formulations
can increase conidial survival and may enhance the efficacy of B. bassiana for
controlling insect pests in epigeal habitats.
Velez and Montoya (1995), studied the effect of exposure to
ultraviolet radiation on the germination of conidia of Beauveria bassiana in
33 REVIEW OF LITERATURE
the laboratory, using oil and water suspensions. They hadn't observed any
direct germination of conidia sprayed to coffee leaf discs and exposed to
ultraviolet radiation for 0-60 minutes. However, B. bassiana sprayed on to
leaf discs in a standard mixture of oils was viable after 60 minute exposure.
They observed differences between different formulations of B. bassiana
sprayed on coffee berries. An increase in exposure time to sunlight resulted in
lower viability.
Fargues, et al. (1996), irradiated conidia from 65 isolates of
Beauveria bassiana, 23 of Metarhizium anisopliae, 14 of Metarhizium
flavoviride and 33 isolates of Paecilomyces fumosoroseus by artificial
sunlight for 0, 1, 2, 4 and 8 hours. They found that, survival decreased with
increased exposure to simulated sunlight. Overall, isolates of M. flavoviride
were the most resistant to irradiation followed by B. bassiana and M.
anisopliae. Conidia of P. fumosoroseus were most susceptible. There was
also an intra species variation.
Hu, et al. (1996), evaluated the pathogenicity of Beauveria bassiana
to the coreid Riptortus linearis in a series of laboratory tests. They found that,
at 25 ° C and above, pathogenicity of B. bassiana decreased with increase in
temperature. They due that to the adverse effect of high temperatures on the
germination of conidia. Ultraviolet irradiation of conidia reduced
pathogenicity of B. bassiana to R. linearis.
Morley-Davies, et al. (1996), screened Metarhizium and Beauveria
spp. conidia with exposure to simulated sunlight and a range of temperatures.
They exposed the isolates to 4, 8, 16 and 24 hours UV light from a sunlight
simulator at 40 °. They found that, conidial viability decreased markedly in
34 REVIEW OF LITERATURE
all isolates with increasing UV exposure. Germination ranged between 10 and
50% after 24 hours exposure to UV.
Varela-A and Morales-R (1996), studied the characterization of some
Beauveria bassiana isolates and their virulence toward the coffee berry borer
Hypothenemus hampei. They found that, the viability of conidia decreased
between 45 and 50°C, with total mortality at 55°C for all isolates. There were
significant differences in susceptibility to ultraviolet radiation and in daily
lipase production.
Tang, et al. (1999), found that, resistance to heat and ultraviolet
radiation of conidia of Beauveria bassiana with different moisture contents
varied significantly within different strains. The effects of radiation occurred
more at higher (RH 85 and 93%) and the lowest (5%) moisture contents,
while 10 and 55% RH had less effect on conidial viability.
Edgington, et al. (2000), found that, unprotected B. bassiana spores
were almost completely inactivated by exposure to 60 minutes of direct
sunlight or 20 second of UV light of 302 nm wave length.
Cagan and Svercel (2001), studied the influence of different doses of
ultraviolet (UV) light on the pathogenicity of the entomopathogenic fungus B.
bassiana against the European corn borer, O. nubilalis, and on the radial
growth of the fungus under laboratory conditions. They found that UV light
exposure significantly influenced the pathogenicity of B. bassiana isolates
against O. nubilalis larvae. Variant SK99C showed the highest level of
infectivity. There are a significant differences between these variants.
Nong, et al. (2005), conducted laboratory experiments to study the
UV-screen effect of 17 UV-protectants and 4 combinations for the conidia of
35 REVIEW OF LITERATURE
Beauveria bassiana, Metarhizium anisopliae and Verticillium lacanii
[Verticillium lecanii]. They found that, UVP-2 (benzotriazole ) was confirmed
to be the most effective protectant. Protective efficiency of UVP-2 to spores
of entomopathogenic fungi was over 90%, and the other 4 UVPs
(benzotriazole 3, oxybenzone 2, sodium uranine and Congo red) were
approximately 60% after 30 minutes exposure of spores to UV. The mixture
of UVPs did not show higher effectiveness compared to single UVPs. The
mixture of groundnut oil and n-hexane was a suitable solute for UVP-2. The
effective concentration of UVP-2 should be higher than 0.75% for the
protection of fungal conidia. After 40 and 180 minute exposure of fungal
conidia to UV light (at lambda 254 nm, lambda 312 nm or lambda 365 nm),
the protective efficiency of UVP-2 could be increased over 90 and 56-77%,
respectively.
II.3.2 Efficiency of Beauveria bassiana against Aphis sp and two-spotted spider mite, Tetranychus cinnabarinus.
Feng, et al. (1990) bioassayed aphid-derived isolates of Beauveria
bassiana (SGBB8601) and Verticillium lecanii (DNVL8701) against 6
species of globally distributed cereal-infesting aphids. And they found that,
B. bassiana was more virulent than V. lecanii. The LC50`s for B. bassiana and
V. lecanii were 2.1×106 and 8.9×105 on Rhopalosiphum maidis. The LT50`s at
all concentration varied between the pathogens and among the aphid hosts,
with B. bassiana tending to kill aphids more rapidly.
Saenz de Cabezon Irigaray Francisco, et al. (2003) determined the
effects of the mycoinsecticide Naturalis-L (Beauveria bassiana conidial
36 REVIEW OF LITERATURE
formulation) on the two spotted spider mite Tetranychus urticae. The lethal
concentration to kill 50% (LC50) for the juvenile stages was 3184 viable
conidia/ml and 1949 viable conidia/ml for adults.
Simova and Draganova (2003) evaluated the virulence of four
isolates of Beauveria bassiana (isolates 311, 312, 339 and 340) and one
isolate each of Metarhizium anisopliae (isolate 17), Paecilomyces farinosus
(isolate 112) and Verticillium lecanii (isolate 289) to the two-spotted spider
mite, Tetranychus urticae. They established that: The isolate 339 of B.
bassiana was the most virulent in experiments with T. urticae. The calculated
values of the median lethal time (LT50) varied within a narrow confidence
interval with 95% confidence limits from 1.293 to 1.420 days; the average
value was 1.355 days.
Nirmala, et al. (2006) studied the pathogenicity of 12 fungal isolates
belonging to Beauveria bassiana, Metarhizium anisopliae and Verticillium
lecanii against Aphis craccivora, Aphis gossypii and Rhopalosiphum maidis
using detached leaf bioassay technique. They found that, all 12 isolates of the
three fungi were pathogenic to A. gossypii, Aphis craccivora and R. maidis.
R. maidis was relatively less susceptible to the three fungi than A. craccivora
and A. gossypii.
II.3.3 Role of Bacillus thuringiensis on the biological control of European Corn Borers Ostrinia nubilalis (Hb.).Coppolino et al. (1984), found that granular formulations of Bacillus
thuringiensis kurstaki more effective than wettable powders, and more
suitable for application in fields containing low densities of Ostrinia nubilalis
37 REVIEW OF LITERATURE
and parasites populations (which are less affected by microbial than by
chemical insecticides).
Lokaj and Marek (1986), found that, Decis [deltamethrin] was
highly effective against Ostrinia nubilalis on maize. Cymbush [cypermethrin]
was also effective. Biological preparations based on Bacillus thuringiensis
and insect growth regulators (Dimilin [diflubenzuron] and Nomolt
[teflubenzuron]) were less effective. They concluded that the success of
treatments depends on the correct timing of applications. The importance of
environmental considerations is emphasized.
McGuire et al. (1990), tested an encapsulated Bacillus thuringiensis
subsp. kurstaki within maize-starch granules with the feeding stimulant Coax
or the UV screen Congo red at 2 field sites against Ostrinia nubilalis feeding
in whorl-stage maize. They found that, all treatments with B. thuringiensis
significantly reduced tunneling by O. nubilalis. At one site, they observed a
significant effects of addition of the phagostimulant. When they added the
coax at 1 or 10% of starch dry weight with 400 IU B. thuringiensis/mg dry
granule weight, the response of O. nubilalis was equivalent to that obtained
with granules containing no feeding stimulant and 1600 IU/mg. Also, granules
with the coax and 400 IU/mg gave a response similar to that obtained with the
commercial product Dipel 10G formulated at 1600 IU/mg. At the other site,
the effect of phagostimulants was not significant, primarily because O.
nubilalis infestation levels were excessively low for precise discrimination
among treatments.
Mile (1993), studied the integrated pest management of European corn
borer (Ostrinia nubilalis Hb) in maize. He reported that, in field trials in
38 REVIEW OF LITERATURE
1990-92, two preparations based on the Bacillus thuringiensis subsp. kurstaki
(Biobit WP at 1.5 kg/ha and Biobit XL at 2.0 liters/ha) gave good results
against the pest.
Burgio et al. (1994), studied the efficacy of Bacillus thuringiensis
Berliner subsp. kurstaki based preparations against European corn borer
infesting pepper Capsicum annuum in greenhouses. They reported that, in
1991, one- and three-week interval treatments using Delfin reduced damage
caused by O. nubilalis compared with the untreated control. In 1992, both
Lepinox and Delfin reduced damage compared with the untreated control, but
there was no statistical difference between the two formulations. Two
treatments against 2nd generation larvae were sufficient to reduce damage.
When attacks by O. nubilalis were high, as in 1992, when the percentage
damage ranged between 34.8 and 43.7, spray intervals of six - seven days
were suggested for effective control. The spreader-sticker Vapor Gard
(pinolene) did not affect the efficacy of B.t. subsp. kurstaki and/or its
persistence.
McGuire et al. (1994a), investigated residual insecticidal activity of
Bacillus thuringiensis encapsulated in corn starch. In the 1st test, they stated
that during a wet year (1990) insecticidal activity of B. thuringiensis
encapsulated in starch granules was greater than that of B. thuringiensis in a
commercial formulation. In a dry year (1989), there were no significant
differences in activity. In 1991, the commercial formulation had less activity
than the two of the starch formulations. In the 2nd test, They examined the
effect of an early (1st day of insect infestation) versus a late application (7th
day of infestation) of toxicants when whorl-stage plants were infested with
39 REVIEW OF LITERATURE
laboratory reared larvae of O. nubilalis over a period of 10 days. They found
that, late application was significantly more effective than early application.
Granules of B. thuringiensis consistently prevented damage by O. nubilalis as
well as or better than a chemical insecticide for the length of the study.
McGuire et al. (1994b), explored the survival of Ostrinia nubilalis
(Hubner) after exposure to Bacillus thuringiensis Berliner encapsulated in
flour matrices. They found that, in the greenhouse and at all 3 field sites, 5 of
these formulations were just as effective as Dipel 10G, a commercially
available B. thuringiensis product, for control of larvae of the pest. In all
greenhouse studies and at one of the three field sites, the dose of B.
thuringiensis could be reduced by as much as 75% when a phagostimulant
was added to flour granules without significant loss of control of O. nubilalis.
The phagostimulant dose response was not observed at the other two field
sites in which larval infestations were relatively low. Flour type had no
significant effect on control of O. nubilalis under greenhouse and field
conditions. Greenhouse evaluations provided results significantly similar to
results from two of the field sites, indicating the usefulness of the technique.
Ridgway et al. (1996), developed a low-cost, granular matrix
formulation of Bacillus thuringiensis subsp. kurstaki, composed primarily of
corn flour and containing a feeding stimulant composed of cottonseed flour
and sugars, for use against Ostrinia nubilalis, on whorl-stage maize. In
laboratory experiments, they indicated that a maize flour agricultural
commodity product was a suitable carrier, that the feeding stimulant enhanced
the activity of B. thuringiensis, and that the granular matrix protected B.
thuringiensis from photo-degradation. In greenhouse test they showed that,
40 REVIEW OF LITERATURE
there was a higher mortality of O. nubilalis on maize plants treated with the
granular matrix than on plants treated with a standard commercial granular
formulation of B. thuringiensis. Mortality with either treatment was increased
by application of simulated rainfall. In a field test, They found that, the
granular matrix applied at a rate of 5.5 kg/ha gave control comparable with
that achieved by the commercial standard applied at a rate of 11 kg/ha. They
indicated that, increased efficacy or reduction in costs of management of O.
nubilalis with B. thuringiensis should be possible through the use of the
granular matrix formulation.
Hafez et al. (1998), reported that, inorganic salts, such as, calcium
oxide, calcium carbonate, zinc sulphate and potassium carbonate at 0.1%
potentiate the activity of the product Dipel 2X (B. t. var. kurstaki) against
Chilo agamemnon and Ostrinia nubilalis in varying degrees. With regard to
protein solubilizing agents, urea, sodium thioglycollate and EDTA enhanced
the potency of B. t. against O. nubilalis with 1.4-2.3 fold increase . The lipid
emulsifying agent Tween 80 (0.5%) caused 1.3 fold increase in the potency of
B. t. With respect to C. agamemnon, sodium thioglycollate and EDTA (0.1%)
were effective in potentiating the activity of B. t. with 3.1 and 1/2 fold
increase, respectively, while urea caused a decrease in the potency of B. t. as
compared with the control. The lipid emulsifying agent Tween 80 (0.5%)
caused 1.3 fold increase in the potency of B. t. The potentiating effect of
aromatic compounds is not obvious with respect to the tested insect species.
With amino acids and amides, it appeared that some of the tested compounds
enhanced the potency of B. t. against the tested insect species but in varying
degrees.
41 REVIEW OF LITERATURE
Ivezic et al. (1998), treated maize (in a field experiment) with 3 liters/
ha of Biobit XL (Bacillus thuringiensis-based) for controlling Ostrinia
nubilalis at the beginning and/or at the end of July, They found that,
infestation levels had of 53, 35 and 37%, respectively, compared with 83% in
the untreated control.
Raspudic et al. (1999), carried out a biological control of ECB on
silage maize with biological preparation Biobit XL (based on Bacillus
thuringiensis) at a dose of 3 liters/ha. They reported that, intensity of attack
was lower for 41%. The number of cavities and larvae/plant also decreased.
On treated plots 0.64 cavities and 0.67 larvae/plant were found, whereas on
the control plots there were 1.61 cavities and 1.79 larvae/plant. Both cavities
and larvae were above the ear, because these were the larvae of the second
generation. Length of damage of maize stems in the control plots was 4.11
cm, and on treated plots 1.28 cm/plant.
Ridgway and Farrar (1999), compared five commercial granular
formulations of Bacillus thuringiensis Berliner marketed for controlling the
European corn borer, Ostrinia nubilalis (Hubner). They stated that, three
formulations, Dipel 10G(R), Full-Bac ECBG(R), and Strike BT(R), were
similar in terms of both mortality and speed of kill. A formulation containing
a strain of B. thuringiensis developed by plasmid fusion, Condor G(R), caused
mortality similar to the other three formulations, but the speed of kill was
slower. A fifth formulation containing a B. thuringiensis toxin produced by
Pseudomonas fluorescens Migula, M-Peril(R), caused substantially less
mortality than any of the other formulations. An experimental water
dispersible formulation, based on a previously developed granular matrix
42 REVIEW OF LITERATURE
formulation containing B. thuringiensis and a nutrient-based phagostimulant,
caused significantly higher mortality of the European corn borer than a similar
formulation without the phagostimulant.
Tamez Guerra et al. (2000), found that, B. thuringiensis stability,
after simulated sunlight (xenon light/8 h) and rain (5 cm/50 min), was
improved using formulations based on lignin, corn flours, or both, with up to
20% of the active ingredient, when compared with technical powder or Dipel
2X in laboratory assays a lignin and lignin + pregelatinized corn flour (PCF)
based formulation showed significantly higher residual activity than Dipel
2X, four and seven days after application.
Pierce et al. (2001), determined the larval susceptibility to
Bacillus thuringiensis for Nosema pyrausta infected and uninfected European
corn borers, Ostrinia nubilalis (Hubner). They disseminated that, LC50 values
for N. pyrausta infected larvae were significantly lowered (P<0.0001) than for
uninfected larvae and declined with increasing levels of infection. LC50 values
for a 15 days bioassay using field colony first instar were 0.006 and 0.027 mg
of Dipel ES/kg of diet for larvae moderately infected by N. pyrausta and
uninfected larvae, respectively. Nosema pyrausta infected larvae reared on
Dipel ES-amended diets produced 70-fold fewer spores (P<0.0001) than
larvae reared on standard diet. Infected larvae also weighed less and failed to
mature on Dipel ES-amended diets. They suggested that B.t corn will have a
direct adverse effect on the survival and continual impact of N. pyrausta as a
regulating factor on European corn borer populations.
43 REVIEW OF LITERATURE
II.4 Oils efficiency against spider mites Tetranychus spp
Rock and Crabtree (1987) examined the activity of petroleum and
cottonseed oils against adult females of Tetranychus urticae and P. ulmi. They
found that, cottonseed oil was less effective against the mites than petroleum
oil.
Butler and Henneberry (1990a) found that, various mixtures of
maize, coconut, palm, safflower, sunflower, groundnut and soyabean oils in
combination with 5 different liquid detergents effectively reduced numbers of
Tetranychus spp. on bush beans Phaseolus vulgaris, peppers and squash.
Butler and Henneberry (1990b) evaluated the acaricidal activity of
cottonseed oil, raw cottonseed oil and insecticidal soap against spider mites,
Tetranychus spp. (on celery). They found that, cottonseed oil induced high
levels of mortality on spider mites.
Sawires (1992) carried out laboratory and field studies to evaluate the
toxicity of maize and camphor oils on Tetranychus arabicus. They showed
that maize oil was more toxic and repellent than camphor oil.
El-Duweini and Sedrak (1997) studied the efficacy of jojoba
(Simmondsia chinensis) oil (canola oil) against different stages of the
phytophagous mite, Tetranychus arabicus, and the adult female of the
predaceous mite Euseius scutalis. They found that, the LC50 and LC90 for T.
arabicus larvae, deutonymphs, adult females and eggs were 0.53 and 4.28,
1.21 and 5.17, 1.60 and 6.35, and 2.53 and 10.86, respectively.
Amer, et al. (2001) tested the direct toxicity of some mineral and plant
oils to the two spotted spider mite Tetranychus urticae Koch eggs and
44 REVIEW OF LITERATURE
females. He found that KZ oil was toxic to the egg stage compared to adult
female. In contrast, the vegetable oil Natur'l has a close toxic effect for both
stages of T. urticae. Bio-dux oil was proved to be toxic to adult female and
relatively in toxic to egg stage.
Lancaster, et al. (2002) evaluated the summer sprays of soyabean oil
for their efficacy against two spotted spider mites (Tetranychus urticae)
(TSSM) on burning bush (Euonymus alatus). They reported that, single
sprays of 1, 2, or 3% soyabean oil or 1% SunSpray reduced TSSM
populations by 97-99% compared to water-sprayed controls. In a second
experiment, a single spray of 0.75, 1.0, or 1.5% soyabean oil reduced the
TSSM population by >95%, compared to the water control. A second spraying
of 0.25-1.5% soyabean oil resulted in <more or ≥ 93% control of TSSM
compared to the water control. A third spray provided little additional TSSM
control.
Lee, et al. (2005) evaluated Bionatrol, specified emulsion nano-
particle soyabean oil, for it's insecticidal efficacy on two spotted spider mites
(Tetranychus urticae), aphids (Aphis gossypii), and white flies (Trialeurodes
vaporariorum) on greenhouse grown english cucumber (Cucumis subsp.
Kasa). They found that, Bionatrol had a relatively high mortality rate against
insects. Bionatrol reduced populations of the insects examined by 88-95%.
II.5 The side effect of bioinsecticides on some beneficial insects.
El-Husseini (1980), showed that treatment with Bactospeine (a
formulation of Bacillus thuringiensis var. thuringiensis was harmless
45 REVIEW OF LITERATURE
against the beneficial insects Labidura riparia and Coccinella
undecimpunctata.
Salama and Zaki (1984), studied the impact of Bacillus thuringiensis
Berl. on the predator complex of Spodoptera littoralis (Boisd.) in cotton
fields. They found that the population curve of the coccinellids (Coccinella
undecimpunctata L., Scymnus interruptus (Goeze) and S. syriacus Mars., the
staphylinid Paederus alfierii Koch, the anthocorids Orius albidipennis (Reut.)
and O. laevigatus (Fieb.) and the chrysopid Chrysoperla carnea (Steph.)
(Chrysopa carnea)) was slightly affected as a result of spraying; this effect
was thought to be related to the population reduction of Spodoptera littoralis,
and the predator populations affected could rebuild together with that of the
host.
Langenbruch (1992), determined the efficacy of B.t. subsp.
tenebrionis on young larvae of Coccinella septempunctata when they had
fed on contaminated aphids [Aphididae]. Larvae of the predator were
unaffected by the recommended dose in the field.
Jayanthi and Padmavathamma (1996), studied the cross infectivity
and safety of nuclear polyhedrosis virus, Bacillus thuringiensis subsp.
kurstaki Berliner and Beauveria bassiana (Balsamo) Vuille to pests of
groundnut (Arachis hypogaea Linn.) and their natural enemies. They found
that Bacillus thuringiensis subsp. kurstaki was highly effective against the
larvae of lepidopterous pests but not against homopteran insects. B.t. was also
safe to coccinellid predators and larval parasitoids of A. modicella, except
adults of C. carnea. Beauveria bassiana was pathogenic to groundnut pests
and coccinellid predators.
46 REVIEW OF LITERATURE
Masarrat and Humayun (1997), showed that the entomogenous
fungus Beauveria bassiana was highly pathogenic to the predatory coccinellid
Coccinella septempunctata.
El-Hamady (1998), found that the commercial preparation of
(L.) Wliczek seedlings were used for rearing aphids' Aphis gossypii, Aphis
craccivora and Rhopalosiphum maidis, respectively according to Zein, et al.
(1982). After 7-15 days aphids were transferred from infested to healthy
seedlings by cutting the heavily infested leaves and placed on the healthy
seedlings.
Contamination between cultures was prevented by placing the
seedlings in special chambers 50×50×60 cm covered with muslin on their
sides. These cultures were kept in a breeding room under the temperature of
25±2°C, 65±5 relative humidity (R.H) and 12 hours daily illumination by
using two fluorescent bulbs of 40 watts each .
III.2 Rearing technique of the two spotted Spider mite, Tetranychus cinnabarinus (Boisduval).
Spider mite T. cinnabarinus (Boisduval) colonies were obtained from
castor bean plants Ricinus communis (L.) at El-Gharbia Governorate and
reared under laboratory conditions on castor bean leaves for about six months
50 MATERIALS AND METHODS
away from any contamination of pesticides before starting the experiments
according to Zein, et al. (1987). About 6-10 seeds of castor bean were
planted in one pot (30 cm. diameter) and left under the green house
conditions for 7-10 days for germination.
After 7-10 days, seedlings were infested by clean culture of red
mites. Mites were always transferred from infested to healthy plants by
cutting heavily infested leaves into small sections and placed on sound
plants. Contamination was prevented by placing these seedlings in special
chambers 50×50×60 cm covered with muslin. These cultures were
maintained in a breeding room under of 25±2°C, 65±5 relative humidity
(R.H) and 12 hours daily illumination by using two fluorescent bulbs of 40
watts each. Mites were collected by placing the infested castor-oil bean
leaves on white paper, then the full mature individuals were chosen and
transferred by a fine brush to leaves discs (1.5 cm diameter) for
experimental tests .
III.3 Rearing technique of the predator, Paederus alfierii (Kock).
The tested predator P. alfierii (Kock) (Rove beetles) was collected
from untreated vegetables fields at Elgharbia Governorate by using an insect
trap.
Predators were placed in glass jars (one litter) covered with muslin.
Aphis sp and egg masses of cotton leaf worm Spodoptera littorals were
offered every day to the predator as a constant supply of food. Predators
were kept under laboratory conditions (temperature 25±2 °C and 65±5 RH
51 MATERIALS AND METHODS
and 12 hours daily illumination by fluorescent light) for at least 2 weeks
before testing (Abd-Allah, 1998).
III.4 Determination of the Beauveria bassiana (Balsamo) potency .
To evaluate the effect of UV radiation on Beauveria bassina
formulation (Biofly), the formulation potencies before and after UV
radiation were determined. Cultures of aphids and spider mite were
maintained under laboratory conditions. Many investigators found that
Beauveria bassina had hight efficiency against spider mites and aphids
(Feng, et al. 1990; Simova and Draganova 2003 and Nirmala, et al.
2006). This experiment aims to study the efficiency of Beauveria bassiana
formulation (Biofly) against three aphid species namely (Aphis gossypii
(Glover), Aphis craccivora (Kock) and Rhopalosiphum maidis (Fitch) and
also its efficiency against spider mite T. cinnabarinus. Both of slid dipping
and leaf-disc dipping techniques were used to determine the most
susceptible species.
III.4.1 Slide dipping technique.The slide dipping technique described by El- Sayed, et al. (1978)
was applied to assay the toxicity of Beauveria bassiana formulation (Biofly)
against aphids. A piece of double faced scotch tape was pressed tightly to
the surface of a glass slide. Using a moist brush, ten adults of aphids (1-2
days old) were stuck to the tape on their backs so that their legs and
antennae were kept free. The slides were then dipped in the Biofly dilutions
(50 : 50000 conidia/ml) and gently agitated for five seconds. Any excess of
52 MATERIALS AND METHODS
the solutions was removed using a filter paper and kept under the same
conditions of the breeding room. Three replicates were used for each
concentration. Forty of insects were also dipped in water according to the
above technique and considered as control check. Mortality counts were
recorded after 24 and 48 hours following treatments. Aphids responding to
touch of a fine brush were considered alive.
III.4.2 Leaf-disc dipping technique:
Four castor bean leaves discs (1.5 cm in diameter) were placed
upside down on a filter paper and put over a wet cotton pad in petri-dish, 9
cm in diameter. Treatments were carried out by immersing the leaf disc in
each pesticidal dilution for five seconds, and the treated discs were left to
dry and returned to the petri-dishes. Ten adult mites were placed on the
exposed surface of each disc and kept under the same conditions of the
breeding room. Each dish contained four discs which considered as four
replications for each dilution. Using microscopical examination, mortality
percentages were counted after 24 and 48 hours, and mites responding to
touch of brush were considered alive (Abo EL -Ghar and El-Rafie, 1961).
III.4.3 Determination the effect of ultra violet radiation on B. bassiana potency.Sunlight and ultra violet radiation significantly reduce the efficiency
of the biological control agents (fungus, bacteria and virus). So, for
obtaining a satisfy biological control, the effect of adding some chosen
photostablizers and oils to the biological agents formulations were
investigated. But this adding may be synergistic or inhibited their efficiency.
53 MATERIALS AND METHODS
So, the investigations divided into two parts as follow:
a- Study the effect of mixing certain oils and photostaplizers with
Beauveria bassiana formulation (Biofly) on its efficiency as a biocontrol
agent.
b-Study the stability of these mixtures under ultra violet radiation.
III.4.3.a Mixing Beauveria bassiana formulation (Biofly) with different oils.
III.4.3.a.a Chemical used :1-Mineral oil (KZ oil)Structural formula Mixture of CH3CnH2nCH3 were n=13-39 atoms and cyclic paraffins
were n=3-17 atoms
Molecular Formula : CnH2n+2 for alkanes and CnH2n for cyclic paraffins were n = 15:40 atoms.Called Volk oil, a refined grade colorless oil distillate on 350°F composed mainly of alkanes (15:40 carbons) and cyclic paraffins (15:40 carbons)
Formulations: :E.C. 95 %.Introduced by :Kafr El - Zayat Company.*Recommended rate of application : 750 cm3 / feddan.2- Paraffin oilStructural formula : the same structure of the mineral oil.Molecular Formula : the same molecular formula of the mineral oil.Introduced by :Elcabten company for oil extracting.
* According to the Ministry of Agricultural technical recommendation for controlling
agriculture pests (2001)
CH2CH2
CH2CH2
CH2
CH2
(CH2)n
(CH2)n
54 MATERIALS AND METHODS
3- Botanical oils: Corn and cotton oilsIntroduced by : Tanta Company for oils and soap. Castor oil Introduced by :Elkabten company for oil extracting.Canola oil Introduced from : National research center, Horticultural department.
4: Beauveria bassiana (Bio-fly)
Formulations : E C. containing 30×106 conidia/ml of Beauveria bassiana.
Introduced by : El-Nasr for biopesticides and fertilizers Company. (Bio.)
*Recommended rate of application : 200 ml/100L
Procedures:In the laboratory, Beauveria bassiana formulation (Biofly) was
mixed with four botanical oils (castor, canola, corn and cotton oil), mineral
and paraffin oils by the ratios of (1 Biofly:1oil, 1:2, 1:3, 2:1 and 3:1 v/v).
The toxicities of different mixtures were tested against spider mites T.
cinnabarinus by using leaf disk dipping method. Mortality percentages were
recorded after 48 hours and corrected according to Abbott`s formula
(1925), and LC50 values with their 95% confidence limits were estimated for
all treatments and compared with the LC50 for the Biofly formulation alone.
* According to the Ministry of Agricultural technical recommendation for controlling
agriculture pests (2001)
55 MATERIALS AND METHODS
III.4.3.b Mixing Beauveria bassiana formulation (Biofly) with Photostablizers and pigments.
Procedures:In laboratory test, Beauveria bassiana formulation (Biofly) was
mixed with 0.1, 0.2, 0.5 and 1% of four photostablizers (benzophenon, 4-
nitophenol, 4-nitro acetophenon and acetophenon) and two pigments, titan
yellow and congo red. All compounds were resolved in 1 ml methyl
alcohol to prepare all the mentioned mixtures. All mixtures and Biofly
formulation were tested against spider mite T. cinnabarinus by using leaf-
disc dipping technique. Mortality percentages were recorded after 48
hours and the LC50 were calculated and compared with the LC50 for the
OH
O O
N
SCH2
NN
OH
OO
N
SCH2
N
NH2
SOH
N N
O O
NH2
SOH
NN
OO
57 MATERIALS AND METHODS
Biofly formulation alone.
III.4.3.c Effect of Ultra Violet radiation (UV) on Beauveria bassiana .Only the most efficient mixtures from the previous experiments were
chosen to study the effect of UV radiation on B. bassiana in the laboratory.
25 ml of each mixtures and the Biofly formulation were placed in 50 ml
pyrex flask. Flasks were stoppered and gently shaken, then kept under UV
light radiation (λ= 254 nm) at 12 cm distance above flasks. Sample of 2.5
ml each was taken at 0, 1, 2, 3, 6, 12 and 24 hours after exposure to UV
light, placed in dark glass bottle. Samples were kept for bioassay test in a
refrigerator (at 4º C).
The LC84 values against spider mite T. cinnabarinus were
calculated from previous experiments and prepared for all mixtures
samples and Biofly formulation. Fifty adult mites were treated with
corresponding concentration by using leaf-disc dipping technique.
Mortality percentages was recorded after 48 hours and estimated the
concentration corresponding to all % mortality to calculate the half life time
T50 for each mixture using the following equation of Moye et al., 1987.
T50=ln 2
K=0.6932
K
K= 1
tx⋅ln abx
Where:
T50 = Half life time (the time needed to reduce the pesticide residue concentration to half )
58 MATERIALS AND METHODS
k = Rate of decomposition . tx = Time in days .
a = Initial residue of pesticide. bx = Concentration residue at x time.
III.5 The side effect of bioinsecticides against the predator, Paederus alfierii (Kock).
Surface deposit technique was used to determine the toxicity of
biochemicals, Agerin, Biofly and their mixtures with oils and
photostaplizers compared with diazinon against the predator Paederus
alfierii (Kock) as described by Moustafa et al., (1980) with slight
modification. The dry film of mixtures was prepared by applying 1 ml
methyl alcohol instead of acetone, containing the desired concentration of
each mixtures on 9 cm diameter petri dish, after the solvent was evaporated,
ten adults (previously exposed to low temperature 4°C for 10 min. to slow
their movement) of the predators were transferred to treated petri dishes and
each treatment was replicated four times. Mortality counts were recorded
after 48 hours after treatment.
III.6 L.D.P lines and statistical analysis.
All insects' mortality percentages results were corrected according
to Abbott`s formula (1925), and plotted on probit graph papers against
insecticide concentrations. Results were statistically analyzed according to
the method of Litchfield and Wilcoxon, (1949). The obtained data
including slopes of the regression lines and LC50 values with their 95%
confidence limits were calculated.
59 MATERIALS AND METHODS
III.7 Evaluation of some chemical insecticides efficiency against ECB on certain maize cultivatrs under natural infestation conditions.
III.7.1 Chemical insecticides used :
1- Diazinon ( Diazinox, Bausudin or Neocidal)Structural formula :
NN
CH3
(CH3)2CH
OP(OCH2CH3)2
S
Chemical name :O,O-diethyl O- 2- isopropyl- 6- methylpyrimidin- 4- yl phosphorothioate.
Molecular Formula :C12H21N2O3PSFormulation :60% E C.Introduced by : Kafr El - Zayat Company. *Recommended rate of application : 1L / feddan.2- Methymoyl (Lannate)
Structural formula :
CH3NHCO2N CSCH3
CH3
Chemical name :S- methyl N- (methyl carbamoyloxy) thioacetimidate.Molecular Formula :C5H10N2O2SFormulation : 90% SP.Introduced by : Kafr El - Zayat Company.* Recommended rate of application : 300 gm./ feddan.
* According to the Ministry of Agricultural technical recommendation for controlling
agriculture pests (2001)
60 MATERIALS AND METHODS
3-Fenpropathrin (Meothrin.)Structural formula :
OCHCNCO2
HCH3
CH3CH3
CH3
Chemical name :(RS)-∝-cyano-3- phenoxybenzyl 2, 2, 3, 3 tetra methyl-cyclopropane, carboxylate .
Molecular Formula :C22H23NO3
Formulation: :E.C. 20 %.Introduced by : Kafr El - Zayat Company.* Recommended rate of application : 750 cm3 / feddan.4-Chlorpyrifos. (Pyriban M)Structural formula
NCl
ClCl
OP(OCH2CH3)2
S
Chemical name :O,O-diethyl O-3, 5, 6- trichloro- 2- pyridyl phosphorothioate.
Molecular Formula :C9H11Cl3NO3PS.Formulation: :48% E C.Introduced by : El-Help for importing and exporting Co.*Recommended rate of application : 1L / feddan .Procedures:
Two field experiments were conducted at El-Gharbia governorate
(Tanta Agriculture Faculty Farm) and El-Behira governorate (OmEl-
Momnen village) during 2003 corn growing season, to evaluate the
* According to the Ministry of Agricultural technical recommendation for controlling
agriculture pests (2001)
61 MATERIALS AND METHODS
efficiency of certain chemical pesticides against ECB infesting different
corn cultivars. Eight white corn cultivars: open pollinated variety (Giza 2),
single cross 10 (S.C.10), S.C.13, S.C.123, three way cross 310 (T.W.C.310),
T.W.C.321, T.W.C.323, T.W.C.324 and two yellow corn cultivars T.W.C.351
and T.W.C.352 were planted at 10th of July(2003) in El-Gharbia region
and at 13th of July (2003) in El-Behira region. Seeds of corn cultivars were
supplied from Agricultural Research Center (A.R.C.), Egypt. The
experiment was designed as strip plot with three replicates. Vertical plots
assigned to the four insecticide treatments plus an untreated one (control).
All treatments were randomized distributed in each replication. Each
vertical strip plot were bordered on each side by two rows of untreated corn
cultivars to minimize the insecticide drift to adjacent plots.
The ten corn cultivars were allocated in horizontal plots which
randomize distributed in each replication as well.
Each plot was 10 rows. Each row (3 m long, 0.7 m apart) which
consisted of 13 plants. All plots received regular agricultural practices. The
pesticides were diluted with water at rate 200 liter/Fadden and sprayed using
a knapsack sprayer (Model CP3) fitted with one nozzle. The spray was
done twice 45 and 60 days after sowing (Metwally and Shehata, 1999). At
harvest time, a random sample consists of 10 plants was taken from each
plot to the laboratory for counting the total number of internodes and holes.
Number of holes per 100 internodes were calculated and recorded. The
stalks were dissected longitudinally to permit the counting of larvae and
cavities. A larvae borrowing cavity represented 2.5 cm long was counted as
one cavity. Also holes No./10 ear stalks and damaged grain percentages
62 MATERIALS AND METHODS
were recorded. The ears of each plot were shelled and weighted in the field.
Grain yields were adjusted to 15.5% grain moisture and a random sample
of 100 grains was weighted and recorded for each plot. 100g grain from
each plot were grained into fine powder and stored in paper package to
determinate nitrogen, protein and phosphorus percentage.
III.7.2 Soil analysis.Soil samples from the experimental sites were collected from
different soil depth (30 and 60cm) and analyzed for soil texture and
chemical properties (Table III.1). In general the soil of the first
experimental site (Experimental Farm of Faculty of Agric., Tanta) was clay
in texture, on the other hand, the texture of the second site (OmEl-Momnen
village - Wady El-Netron, El-Behira Governorate) was sandy in texture, all
soil had fairly uniforms without distinct changes in the texture and is not
saline or sodic. The physical and chemical properties of soil samples were
determined according to the outlined methods of Klute, (1986) and Page,
(1982), respectively.
III.7.3 Climatological elements.Climatological elements values were obtained from the Kotour (El-
Gharbia Governorate) and Wady El-Netron (El-Behira Governorate)
meteorological stations. The maximum and minimum air temperature
monthly means (°C) and averages of relative air humidity (RH%) at El-
Gharbia and El-Behira Governorate during the 2003 seasons are estimated
and summarized in Table (III.2).
63 MATERIALS AND METHODS
Table III.1: Some physical and chemical characters of the experiment soils.
LocationEl-Gharbia site El-Behira site
Soil depth (cm) Soil depth (cm)
Soil characteristics 0-30 30-60 0-30 30-60
Chemical analysis
E.C conductivity (paste extract) (dS/m)
2.6 2.1 2.3 2.2
pH 7.82 7.94 7.9 7.8
Organic matter % 0.91 0.53 1.88 1.42
Soil texture
Sand% 16.19 9.13 92.29 94.46
Silt% 40.14 42.14 2.4 1.34
Clay % 43.48 48.20 3.43 2.78
Table III.2: The monthly average of temperature and relative humidity during 2003 season in both locations.
Month
El-Gharbia site El-Behira site
Temperature º C
Max. Min. MeanRH%
Temperature º C
Max. Min. MeanRH %
July 35.14 24.91 30.03 66.47 35.4 21.7 28.55 48.5
August 35.72 24.54 30.13 66.18 35.8 22 28.9 52.2
September 33.59 22.18 27.89 64.55 33.2 20.2 26.7 50.5
October 28.87 18.17 23.52 64.63 30.7 17.8 24.25 54.2
November 28.7 19.5 23.8 52.4 26.1 14.9 20.5 60.8
64 MATERIALS AND METHODS
III.8 Evaluation of some microbial insecticides efficiency against ECB on certain maize cultivars compared with chemical insecticide under natural infestation conditions.
Chemical used:
Biopesticides
1-: Bacillus thuringiensis subsp. aegyptia.(Agerin)Formulation : 6% Wettable power containing 32×106 IU/mg of
Bacillus thuringiensis subsp. aegyptia.Introduced by : Bioagro-International-Egypt. It was used in Egypt by
permission from Agriculture Genetic Engineering Institute, Agriculture Research Center, Ministry of Agriculture.
Aphis gossypii (LC50`s:9.1×103, 5.65×104, 2.20×105, and 2.67×105 conidia/ml,
72 RESULTS AND DISCUSSION
respectively. From previously mentioned results it could be concluded that: the
most susceptible species against Beauveria bassiana formulation (Biofly) and
suitable to use as an indicator to Beauveria bassiana potency is the adults of
Tetranychus cinnabarinus mite. These results are accordance with many
investigators who had found that Beauveria bassiana had hight virulence against
two-spotted spider mite Tetranchus cinnabarinus and many aphid species such as
Nirmala, et al., 2006; Simova and Draganova, 2003; Saenz de Cabezon
Irigaray Francisco et al., 2003 and Feng, et al., 1990.
73 RESULTS AND DISCUSSION
Table IV.1: Toxicity of Beauveria bassiana against some aphid species and two-spotted spider mite Tetranychus cinnabarinus by using slide dipping and leaf-disc dipping technique respectively.
1085.7, 1559.2, and 2525.2 ppm respectively. Many authors had reported that
mineral and botanical oils had hight efficiency against spider mite either in
laboratory or under field conditions Lee et al., 2005; Lancaster et al., 2002;
Amer et al., 2001; El-Duweini and Sedrak, 1997; Sawires, 1992; Butler and
Henneberry, 1990a,b and Rock and Crabtree, 1987.
77 RESULTS AND DISCUSSION
Table IV.2: Toxicity of some botanical oils and mineral oil against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Fig IV.2: Probit regression lines for the toxicity of some botanical oils and mineral oil to two-spotted spider mite Tetranychus cinnabarinus.
79 RESULTS AND DISCUSSION
IV.2.1.b Effect of Beauveria bassiana mixtures with oils against two-spotted spider mite Tetranychus cinnabarinus.
The toxicity of Beauveria bassiana mixtures with certain botanical oils,
mineral oil and parraffin oil on the adults' spider mite Tetranychus cinnabarinus
(TablesIV.3:IV.7) Show that:
When Biofly mixed with oils by the ratio 1Biofly:3oils, 1Biofly:2oils, and
1Biofly:1 oil, the mixtures` toxicities decreased compared with the Biofly
formulation alone (Tables IV.3-IV.5). On the other hand in case of mixing Biofly
with oils by the ratio 2Biofly :1 oils (Table IV.6), all mixtures were more toxic
than the Biofly formulation alone except the mixture of corn oil which was less
toxic than Biofly formulation alone. In case of mixing Biofly with oils by the
ratio 3Biofly :1 oils (Table IV.7), the mixtures` toxicities increased compared
with the Biofly formulation alone except the mixture of cotton oil which was less
toxic of Biofly formulation alone.
From the previous data it could be concluded that: in all tested oils, there
are a negative relationship between oil ratio in the mixtures and mixtures
toxicities. Most tested mixtures of corn and cotton oils had decreased the toxicity
of the Beauveria bassiana formulation (Biofly) against Tetranychus
cinnabarinus adult mites. On the other hand, mixture No.5 (3Biofly:1oil) of
caster, canola, mineral and paraffin oils had increased the toxicity of the
Beauveria bassiana formulation (Biofly) against Tetranychus cinnabarinus adult
mites. Several working including Maranga et al., 2005;Wekesa et al., 2005;
Manjula et al., 2003; Kaaya, 2000; Ma, et al., 1999; Huang, 1995 and Batista-
Filho et al., 1994 found that conidia formulated in oil outperformed the ones
80 RESULTS AND DISCUSSION
formulated in water. These findings may be due to that oil had synergistic effect
to Beauveria bassiana (Batista-Filho, et al., 1995). That synergistic effect may be
due to enhanced the conidia germination ( Ramle et al., 2004 and Gurvinder et
al., 1999). Also, oil formulations had many advantages compared with water
formulations. Oil could protect the fungal conidia from the UV of sunlight (Moore
et al., 1993) and can give some protection to the conidia from heat (Scherer et al.,
1992). Oil formulations spread rapidly over the hydrophobic surface of leaves
(Burges, 1998) and oil drift evaporates more slowly than water, thus giving the
conidia more time to germinate and infect. Oil formulations also enhances
adhesion of the conidia to the insect cuticle, spreading of oil on the cuticle may
carry conidia into niches on the host cuticle (e.g., inter-segmental folds) that
provide moisture for germination and gave more protection from solar radiation
(Ibrahim et al., 1999). The other advantages of oil over water formulation include
the ready suspension of the lipophilic conidia of B. bassiana in oil (Prior et al.,
1988). But in case of corn oil the results disagree with the findings of Yasuda et
al., 2000, who found that, formulations of Beauveria bassiana conidia in a 10%
corn oil mixture showed more superior infectivity in both sexes of Cylas
formicarius than the formulation of conidia only in laboratory assays. Also,
(Grimm, 2001; Batista-Filho et al., 1995a, b; Smart and Wright, 1992)
reported that cottonseed, soybean, and mineral oils do not adversely affect the
viability of B. bassiana. The antagonism between B. bassiana, corn and cotton oil
may be due to their contents of fatty acids myristic, palmitic, stearic, oleic,
linoleic and arachidic which inhibited both growth and lipase production
(Hegedus and Khachatourians, 1988).
81 RESULTS AND DISCUSSION
Table IV.3: The toxicity of Biofly mixtures with different oils by the ratio (1:3 v/v) on two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Table IV.4: The toxicity of Biofly mixtures with different oils by the ratio (1:2 v/v) on two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Table IV.5: The toxicity of Biofly mixtures with different oils by the ratio (1:1 v/v) on two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Table IV.6: The toxicity of Biofly mixtures with different oils by the ratio (2:1 v/v) on two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Table IV.7: The toxicity of Biofly mixtures with different oils by the ratio (3:1 v/v) on two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
IV.2.2 Effect of Mixing Beauveria bassiana formulation (Biofly) with photostaplizers.All photostaplizers and pigments had no toxicity effect against adults of
two-spotted spider mite Tetranychus cinnabarinus up to 104 ppm. The toxicity of
the Biofly/photostaplizers mixtures to the adults of Tetranychus cinnabarinus, LC50
values and their confidence limits are recorded in Tables (IV.8:IV.12).
In case of mixing Biofly formulation with the acetophenone (Table IV.8):
results reveled that, The most toxic mixture was mixture No.1 (Biofly+0.1%
acetophenone) with LC50 value =6.45×103 conidia/ml while the lowest toxic one
was mixture No.4 (Biofly + 1% acetophenone) with LC50 value =2.68×105
conidia/ml.
In case of mixing Biofly formulation with the 4−nitro acetophenon
(Table IV.9), mixture No.1(Biofly + 0.1% acetophenon) was the most toxic one
(LC50 =2.48×102), on the other hand mixture No.4 (Biofly+1% acetophenon) was
the lowest toxic one (LC50 =9.68×104).
In case of mixing Biofly formulation with the 7−nitophenol (Table IV.10),
results revealed that: adding 0.1% 7−nitophenol (mixture No.1) to Biofly
formulation reduced the Biofly LC50 value to 5.57×103 conidia/ml, while adding
1% 7−nitophenol to Biofly formulation (mixture No. 4) make the mixture almost
non toxic to Tetranychus cinnabarinus mites (LC50 more than 107 conidia/ml).
In case of mixing Biofly formulation with the benzophenon(Table IV.11),
the mixture No.1(Biofly + 0.1% benzophenon) was the most toxic mixture where
LC50 value = 1.21×104 conidia/ml and the lowest toxic one was mixture No.4
(Biofly + 1% benzophenon) LC50 value = 3.07×104conidia/ml.
87 RESULTS AND DISCUSSION
In case of mixing Biofly formulation with the titan yellow pigment
(Table IV.12), data showed that, increasing of titan yellow pigment percentage
enhanced the toxicity of Biofly mixtures. There are a negative relationship
between pigment concentration in the mixture and the mixture toxicity . The most
value=4.89×102) and mixture No.4 (Biofly + 1% Titan yellow pigment) was the
lest toxic one (LC50 value =2.02×104 conidia/ml).
When congo red pigment mixed with Biofly formulation (Table IV.13),
also the mixtures` toxicities enhanced compared with the Biofly formulation alone
but with the increase of pigment ratio the LC50 values increased. Where, mixture
No.1 (Biofly + 0.1% congo red pigment) had LC50 value = 3.55×103 conidia/ml
while mixture No.4 (Biofly + 1% congo red pigment) had LC50 value = 9.90×104
conidia/ml.
Generally. All compound had increased the mixtures toxicities to Teteranychus
cinnabarinus mites, but when increasing the compound ratio to 1% the toxicity
decrease. Similar results were obtained by Nong et al., 2005 and Inglis et al.,
1995.
88 RESULTS AND DISCUSSION
Table IV.8: Toxicity of the Biofly mixtures with the acetophenone (photostabilizer) against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Table IV.9: Toxicity of the Biofly mixtures with the 4-nitro acetophenon (photostabilizer) against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Table IV.10: Toxicity of the Biofly mixtures with the 7-nitophenol (photostabilizer) against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Table IV.11: Toxicity of the Biofly mixtures with the benzophenon (photostabilizer) against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Table IV.12: Toxicity of the Biofly mixtures with the titan yellow pigment against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Table IV.13: Toxicity of the Biofly mixtures with the congo red pigment against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
IV.2.3 Effect of Ultra Violet radiation (UV) on Beauveria bassiana mixtures.The most efficient mixtures from the previous experiment (which had no
adverse effect on Beauveria bassiana potency), had been subjected to study it's
stability under UV radiation. The chosen mixtures had been exposed to UV
radiation for 1, 2, 3, 6 and 12 hours and after that, their potency against two-
spotted spider mite T. cinnabarinus had been evaluated by leaf disk dipping
technique and the half life T50 had been estimated from the corresponding
concentration (Tables IV.14 and IV.15).
In case of Biofly/oils mixtures(Table IV.14): based on the obtained data,
The most persistence mixtures were 3Biofly:1paraffin oil and 3Biofly:1 castor oil
(spider mites mortality % had 36 and 12 after 6hours of exposure to UV radiation
and T50= 1.47 and 1.74 hours respectively) while, 3 Biofly:1mineral oil had the
lowest value in this respect ( mortality % was 14% after exposure to UV
radiation for 3 hours and the T50 =0.90 hour).
Table IV.14: The effect of exposure to UV radiation interval on the efficiency of Beauveria bassiana mixtures with botanical and mineral oils against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
Oils Mixing ratio (v/v)UV irradiation time (hours)
In case of Biofly/photostablizers mixtures: from Table IV.15 , it could be
concluded that, the most persistence mixtures had Biofly + 0.1 % benzophenon,
95 RESULTS AND DISCUSSION
Biofly +0.5% congo red and Biofly+0.1% 7-nitrophenol mixtures (which had
64, 54 and 34 mortality percentage and T50 were 5.71, 4.981 and 3.141 hours
respectively) while acetophenon had the lowest values in this respect which had
lost there efficiency against the spider mites after exposure to UV radiation for
two hours of. These findings in somewhat agree with those of Nong, et al. (2005)
and Inglis, et al. (1995).
Table IV.15: The effect of exposure to UV radiation interval on the efficiency of Beauveria bassiana mixtures with some photostabilizers against two-spotted spider mite Tetranychus cinnabarinus by using leaf disk dipping technique.
grains percentage, 100 grains weight and grains yield/10 plants. Also, the total
nitrogen, protein and phosphorus percentage in corn grains were determined in all
treatments.
97 RESULTS AND DISCUSSION
IV.3.1 Susceptibility of corn cultivars at the late season to infestation with ECB under natural infestation conditions. Susceptibility of ten corn cultivars to infestation with ECB in El-Gharbia
and El-Behira governorates under natural infestation conditions is presented in
Table (IV.16).
In all locations and from average data it could be concluded that: single
cross hybrid 13 (S.C.13) and three way cross 351 (T.W.C. 351) were the most
tolerant cultivars while, T.W.C.323 and T.W.C.324 were the most susceptible
cultivers when ECB infestation evaluated by holes No./100 internodes, cavities
No./10plants and larvae No./10plants.
In case of holes No./10 ear stalks, the most susceptibility cultivers were
S.C10 and T.W.C.324 while S.C.13 and T.W.C. 351 were the most tolerant
cultivers in this regard.
In case of damaged grains percentage, cultivars T.W.C.324, T.W.C.310
and S.C.10 had recored the highest values in this respect while, cultivars
T.W.C.351 and S.C.13 had recored the lowest values.
There is a positive relationship between grain protein percentage and the
damaged grain percentage, while there is no relationship between phosphorous
percentage and damaged grains percentage.
Generally: The most tolerant cultivars against ECB infestations were
S.C.13, T.W.C. 351 and S.C.123 cultivars but the rank between them differed
from location to another and between studied parameters, also cultivars S.C.10 and
T.W.C. 324 had the highest values of holes No./10 ear stalks and damaged grain
percentage, because of S.C.10 cultivar has the longest ear stalk, a hight protein
98 RESULTS AND DISCUSSION
percentage in the grains, also cultivar S.C.10 had been planted for a long time in
Egypt which break down there tolerance to ECB infestation.
Cultivars T.W.C 310, T.W.C .324 and T.W.C. 321 had the highest values
in damaged grains percentage that because of the ear shelling did not cover the
top of the ears this allow the ECB larvae to tunneling the ears beside the hight
protein content of the cultivers grains. Cultivars T.W.C 351 had tolerant to ECB
infestations because of it's early mature, hardest grains and well ears shelled.
Cultivar S.C.13 had tolerant to ECB infestations due to low protein content in the
grain and its thin stem (lowest diameter between all cultivers).
Table (IV.17) shows the data of 100 grains weight, grains yield and grains
yield reduction as a result of natural infestation with ECB on ten corn cultivars
at El-Gharbia and El-Behira governorates. Cultivars S.C.10, T.W.C324 and Giza 2
had the highest values of 100 grain weight while T.W.C. 351, S.C.13 have the
lowest values, in both locations. Cultivars S.C10 and T.W.C324 had the highest
values in grain yield/10plants while T.W.C 323 and SC.13 had the lowest values in
this respect. From the obtained data we can conclude that: The rank of cultivars
differed from location to another, but within locations data, S.C.10 has the
highest values of 100 grain weight and grains yield/10 plants. Similar results
were reported by other researchers including Metwally and Barakat, 2003;
Sadek et al., 1997 and Lutfallah et al., 1991, who found that tested maize
cultivars show different responses to corn borer infestation. Cultivars S.C.10, 123,
129, S.C.161 and T.W.C.321 expresses resistant to Ostrina nubilalis infestation
and has less grain reduction T.W.C.310, 323, 324, S.C.122, 124 and 155
express susceptible to ECB infestation and have as much loss in yield as did other
cultivars.
99 RESULTS AND DISCUSSION
Table IV.16: Susceptibility of ten corn cultivars to infestation with ECB in El-Gharbia and El-Behira governorates under natural infestation conditions(2003 season).
El-Gharbia site
Cultivars Holes No./100 internods
Cavities No./10plants
Larvae No./10plants
Holes No./ 10 ear stalks
Damaged grains%
Grains protein %
Grains phosphorus%
Giza 2 22.4d* 26.3 b 17.7 c 8.67 cd 4.46 cd 3.96 b 0.48 aS.C.10 23.2cd 30.0 b 22.7 b 13.00 a 7.51 a 3.33 de 0.49 aS.C.13 8.4g 9.0 e 7.0 de 5.00 f 2.26 g 3.27 ef 0.43 bS.C.123 13.7ef 16.0 cd 11.3 d 6.33 d-f 4.39 de 4.50 a 0.50 a
T.W.C. 310 17.3e 19.0 c 17.0 c 8.00 c-e 9.01 a 3.83 bc 0.35 dT.W.C. 321 26.6bc 30.0 b 27.0 ab 8.33 cd 7.58 b 3.08 ef 0.48 aT.W.C. 323 32.9a 37.0 a 29.7 a 10.00 bc 3.48 ef 3.04 f 0.37 cdT.W.C. 324 30.2ab 35.7 a 30.0 a 11.33 ab 9.17 a 3.58 cd 0.40 bcT.W.C. 351 11.4fg 10.3 e 6.0 e 5.00 f 3.16 fg 4.02 b 0.50 aT.W.C. 352 14.3ef 13.3 de 9.0 de 5.67 ef 5.33 c 3.76 bc 0.51 aL.S.D (0.05) 3.796 3.796 4.828 2.414 0.1935 0.2625 0.0515
El-Behira siteGiza 2 10.7 e 13.3 e 11.3 d 7.67 de 4.37 d 4.17 a 0.49 aS.C.10 18.2 cd 24.0 cd 24.7 b 15.67 a 6.71 b 3.28 c 0.50 aS.C.13 6.7 f 8.7 e 6.0 e 7.00 e 2.29 f 3.22 c 0.42 bcS.C.123 9.1 ef 13.0 e 10.3 de 5.67 e 4.40 d 4.31 a 0.49 a
T.W.C. 310 18.3 cd 26.7 c 24.7 b 10.33 cd 8.95 a 3.71 b 0.35 deT.W.C. 321 15.3 d 20.0 d 18.0 c 10.67 c 7.33 b 3.24 c 0.47 abT.W.C. 323 25.4 ab 32.7 b 28.0 b 12.33 bc 3.47 e 3.05 c 0.40 cdT.W.C. 324 26.5 a 38.7 a 34.3 a 13.67 ab 8.61 a 3.57 b 0.34 eT.W.C. 351 10.4 ef 10.3 e 8.3 de 4.67 e 2.89 ef 3.81 b 0.52 aT.W.C. 352 22.1 bc 24.3 cd 18.0 c 7.67 de 5.54 c 3.61 b 0.50 aL.S.D (0.05) 3.880 5.496 4.546 2.819 0.8840 0.2675 0.05147
**Averaged data Giza 2 16.6 d 19.8 c 14.5 c 8.17 de 4.42 d 4.06 b 0.49 bcS.C.10 20.7 bc 27.0 b 23.7 b 14.33 a 7.11 b 3.31 e 0.50 abS.C.13 7.5 f 8.8 e 6.5 e 6.00 f 2.27 f 3.25 ef 0.42 dS.C.123 11.4 e 14.5 d 10.8 d 6.00 f 4.40 d 4.41 a 0.50 ab
T.W.C. 310 17.8 cd 22.8 bc 20.8 b 9.17 d 8.98 a 3.77 cd 0.35 fT.W.C. 321 21.0 b 25.0 b 22.5 b 9.50 cd 7.46 b 3.16 ef 0.48 cT.W.C. 323 29.1 a 34.8 a 28.8 a 11.17 bc 3.47 e 3.04 f 0.38 eT.W.C. 324 28.4 a 37.2 a 32.2 a 12.50 ab 8.89 a 3.57 d 0.37 eT.W.C. 351 10.9 e 10.3 de 7.2 e 4.83 f 3.02 e 3.92 bc 0.51 aT.W.C. 352 18.2 b-d 18.8 c 13.5 cd 6.67 ef 5.43 c 3.68 d 0.51 aL.S.D (0.05) 3.177 4.213 3.566 1.926 0.6886 0.2122 0.01628
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars.
100 RESULTS AND DISCUSSION
Table IV.17: 100 grain weight, grains yield and grains yield reduction as a result of natural infestation with ECB on ten corn cultivars at El-Gharbia and El-Behira governorates.
El-Gharbia site
Cultivars 100grains weight(g)Grains yield /10plants (kg)Mean Reduction%***
Giza 2 29.0 ab* 1.26 a 28.57S.C.10 31.4 a 1.51 a 33.77S.C.13 23.0 c 1.05 bc 22.86S.C.123 26.0 bc 1.46 a 30.82
T.W.C. 310 29.6 ab 1.16 a-c 25.86T.W.C. 321 29.5 ab 1.38 ab 28.26T.W.C. 323 25.7 bc 0.97 c 27.84T.W.C. 324 28.7 ab 1.47 a 36.05T.W.C. 351 27.0 b 1.37 ab 22.63T.W.C. 352 27.7 ab 1.30 a-c 36.15L.S.D (0.05) 3.894 0.366
El-Behira siteGiza 2 35.3 ab 1.37 d 23.36S.C.10 36.7 a 1.42 bc 26.76S.C.13 31.0 ef 1.18 e 33.90S.C.123 32.8 de 1.22 de 20.49
T.W.C. 310 33.2 cd 1.24 c 33.87T.W.C. 321 33.6 b-d 1.44 bc 19.44T.W.C. 323 32.0 d-f 1.05 a 21.90T.W.C. 324 35.0 a-c 1.47 a 27.89T.W.C. 351 30.8 f 1.30 b 16.92T.W.C. 352 31.0 ef 1.35 de 20.74L.S.D (0.05) 1.914 0.283
**Averaged dataGiza 2 32.15 a 1.31 ab 26.72S.C.10 34.05 a 1.47 a 29.93S.C.13 27 d 1.11 cd 29.73S.C.123 29.4 bc 1.34 a-c 26.12
T.W.C. 310 31.4 b 1.20 b-d 30.00T.W.C. 321 31.55 b 1.41 ab 23.40T.W.C. 323 30.4 b 1.01 d 24.75T.W.C. 324 31.8 ab 1.47 a 31.97T.W.C. 351 28.9 bc 1.34 a-c 19.40T.W.C. 352 29.95 b 1.33 a-c 27.82L.S.D (0.05) 2.032 0.252
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars.*** Reduction%=(Grain yield in diazinon treatments-Grain yield in control treatment)/ Grain yield in control×100
101 RESULTS AND DISCUSSION
IV.3.2 Insecticides efficiency against European Corn Borer Ostrinia nubilalis (Hb.) infestation.
IV.3.2.a Holes No./100 internodes. Efficiency of four chemical insecticides against ECB infestation on ten
corn cultivars evaluated by holes No./100 internodes at two different locations
are presented in Table (IV.18). At the two locations there are a significant
differences between the insecticides treatments.
At El-Gharbia site: diazinon treated cultivatar S.C.13 and S.C.123, and
chlorpyrifos treated cultiver S.C.13 had the lowest value in holes No./100
internodes.
Holes No./100 internodes values of chlorpyrifos treated cultivers were in
ascending order as follows: S.C.13< S.C.123< T.W.C. 351<T.W.C.
310<T.W.C.352< Giza 2<T.W.C. 324<T.W.C. 323<S.C.10<T.W.C. 321.While
diazinon treated cultivers could be arranged ascendingly as follows: S.C.13<
S.C.123< Giza 2< T.W.C. 310< S.C.10< T.W.C. 324< T.W.C.321<T.W.C. 351<
T.W.C. 352 <T.W.C. 323. Methomyl treated cultivers were in ascending order as
In all locations and from averaged data it could be concluded that: diazinon
treated cultivar S.C.10 and T.W.C.324, and chlorpyrifos treated cultivar T.W.C.324
treatments had the highest values in grain yield/10plants while untreated
T.W.C.323 and S.C.13 and methomyl treated cultivars T.W.C.323 had the
lowest values in this respect. Diazinon followed by chlorpyrifos treatments had
the highest value in grains yield/10plants, while the control and methomyl
treatments had the lowest values in this regard.
From the previous data we can conclude that:
● The most potent insecticides against ECB infestation were diazinon
followed by fenpropathrin. Which reduced the holes No./100 internodes,
cavities No./10plants, holes No./10 ear stalks and larvae No./10plants in
all locations, while methomyl was the least toxic one.
● In case of yield and yield component :Diazinon insecticide had the
highest values in 100grain weight and grains yield/10plants followed by
chlorpyrifos in both locations.
These findings are in accordance with those obtained by Barbulescu 1971 ;
Hills et al., 1972; Martel and Hudon, 1978; Melia Masia and Almajano
Contreras, 1973; Mustea, 1977; Thompson and White, 1977 and Voinescu and
Barbulescu, 1986 who is found that diazinon was the most potent insecticides
against ECB infestation.
This results may be due to that diazinon had high vapor pressure (1.2×10-2
115 RESULTS AND DISCUSSION
Pa at 25° ), stomach and respiratory actions, long half life (Sattar, 1991; Gonzalez
and Aravena-C, 1990 and Smith et al., 1998). On the other hand, Rinkleff et al.,
1995 found that methomyl had a low residual toxicity to Ostrina nubilalis
neonates. That maybe due to that methomyl had shortest half life (T50 =0.91days)
(Wilwam and Sundararajan, 1986) and low stability at room temperature in
aqueous solutions and the rate of decomposition increase in higher temperature, in
presence of sunlight and on exposure to air.
116 RESULTS AND DISCUSSION
Table IV.18: Efficiency of four chemical insecticides against ECB infestation on ten corn cultivars evaluated by holes number/100 internodes in the two locations.
El-Gharbia
CultivarsTreatments
Control Chlorpyrifos Diazinon Methomyl FenpropathrinMean Mean R%*** Mean R% Mean R% Mean R%
Giza 2 22.41d* 8.23 abc 63.30 3.57abc 84.09 15.17 b 32.30 3.82b 82.97S.C.10 23.24cd 10.77 a 53.65 4.23abc 81.80 16.14 b 30.54 8.87a 61.85S.C.13 8.38g 1.96 e 76.56 1.92c 77.07 4.36 d 47.91 4.11b 50.91S.C.123 13.65ef 3.41 de 75.05 2.94bc 78.44 9.88 c 27.63 4.36b 68.06
T.W.C. 310 17.26e 5.15 c-e 70.15 4.09a-c 76.30 8.39 c 51.35 5.11b 70.38T.W.C. 321 26.65bc 10.85 a 59.30 5.30a-c 80.10 24.57 a 7.80 6.43ab 75.87T.W.C. 323 32.92a 9.79 ab 70.27 7.10a 78.42 16.75 b 49.12 9.59a 70.87T.W.C. 324 30.23ab 9.57 ab 68.33 5.16a-c 82.92 16.52 b 45.35 4.46b 85.25T.W.C. 351 11.42 fg 3.54 de 69.03 5.33a-c 53.32 7.65 cd 33.04 3.87b 66.10T.W.C. 352 14.32ef 6.01 b-d 58.01 6.35ab 55.62 8.27 c 42.24 7.33ab 48.83
Mean 20.05A 6.93 C 65.45 4.60D 77.05 12.77 B 36.29 5.79CD 71.10L.S.D (0.05) for pesticides treatments =1.246 for interactions =3.796
El-BehiraGiza 2 10.70 d 3.54 a 66.94 2.65b 75.23 7.39 bc 30.96 2.77ab 74.13S.C.10 18.24bc 5.32 a 70.81 2.60b 85.76 9.03 ab 50.50 3.64ab 80.02S.C.13 6.66e 3.65 a 45.19 2.37b 64.45 5.93 bc 10.99 1.92b 71.14S.C.123 9.09de 2.46 a 72.91 1.55b 82.89 4.92 c 45.87 3.03ab 66.70
T.W.C. 310 18.28bc 5.69 a 68.90 2.45b 86.59 8.67 a-c 52.59 3.59ab 80.35T.W.C. 321 15.33c 3.69 a 75.94 3.05b 80.08 11.65 a 24.01 4.28ab 72.06T.W.C. 323 25.36a 4.17 a 83.56 2.33b 90.82 8.85 ab 65.09 3.52ab 86.10T.W.C. 324 26.49a 5.78 a 78.20 7.38a 72.15 12.44 a 53.04 4.21ab 84.11T.W.C. 351 10.42de 2.24 a 78.54 1.71b 83.63 5.86 bc 43.75 3.50ab 66.39T.W.C. 352 22.05b 5.65 a 74.38 3.98ab 81.95 12.22 a 44.59 6.10a 72.35
Mean 16.26A 4.22 C 74.06 3.01C 81.51 8.69 B 46.53 3.66C 77.51L.S.D (0.05) for pesticides treatments =1.525 for interactions =3.880
Average data**Giza 2 16.56d 5.88 ab 64.48 3.11ab 81.23 11.28 cd 31.87 3.29bc 80.11S.C.10 20.74bc 8.05 a 61.19 3.41ab 83.54 12.59 bc 39.32 6.25ab 69.84S.C.13 7.52 f 2.81 b 62.66 2.14b 71.48 5.15 g 31.56 3.02c 59.87S.C.123 11.37e 2.93 b 74.19 2.25b 80.22 7.40 e-g 34.92 3.69a-c 67.52
T.W.C. 310 17.77cd 5.42 ab 69.51 3.27ab 81.60 8.53 d-f 51.99 4.35a-c 75.51T.W.C. 321 20.99b 7.27 a 65.38 4.18ab 80.09 18.11 a 13.72 5.36a-c 74.48T.W.C. 323 29.14a 6.98 a 76.06 4.71ab 83.82 12.80 bc 56.07 6.56a 77.50T.W.C. 324 28.36a 7.67 a 72.94 6.27a 77.89 14.48 b 48.94 4.33a-c 84.72T.W.C. 351 10.92e 2.89 b 73.57 3.52ab 67.78 6.75 fg 38.15 3.69a-c 66.23T.W.C. 352 18.18b-d 5.83 ab 67.93 5.17ab 71.58 10.24 c-e 43.66 6.71a 63.09
Mean 18.15A 5.57 C 69.30 3.80D 79.05 10.73 B 40.88 4.73CD 73.97L.S.D (0.05) for pesticides treatments =1.191 for interactions =3.177
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars. ***R%= ( control-treatment)/ control×100
117 RESULTS AND DISCUSSION
Table IV.19: Efficiency of four chemical insecticides against ECB infestation on ten corn cultivars evaluated by cavity number/10plants in the two locations.
El-Gharbia
CultivarsTreatments
Control Chlorpyrifos Diazinon Methomyl FenpropathrinMean Mean R%*** Mean R% Mean R% Mean R%
Mean 21.92A 6.39 C 70.86 4.27D 80.50 12.08B 44.87 5.27CD 75.97L.S.D (0.05) for pesticides treatments =1.358 for interactions =4.213
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars. ***R%= ( control-treatment)/ control×100
118 RESULTS AND DISCUSSION
Table IV.20: Efficiency of four chemical insecticides against ECB infestation on ten corn cultivars evaluated by larvae number/10plants in the two locations.
El-Gharbia
CultivarsTreatments
Control Chlorpyrifos Diazinon Methomyl FenpropathrinMean Mean R%*** Mean R% Mean R% Mean R%
Giza 2 17.67c* 4.67ab 73.58 2.00 a 88.68 13.00bc 26.42 3.00b 83.02S.C.10 22.67b 8.00a 64.71 1.33 a 94.12 14.33b 36.76 6.00a 73.53S.C.13 7.00de 1.37b 80.42 1.44 a 79.37 3.33e 52.38 3.00b 57.14S.C.123 11.33d 2.33b 79.41 1.33 a 88.24 8.33cd 26.47 3.33b 70.59
Mean 18.05A 4.79C 73.49 2.09 D 88.43 10.63B 41.09 3.98C 77.93L.S.D (0.05) for pesticides treatments =1.191 for interactions =3.566
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars. ***R%= ( control-treatment)/ control×100
119 RESULTS AND DISCUSSION
Table IV.21: Efficiency of four chemical insecticides against ECB infestation on ten corn cultivars evaluated by holes number/10 ear stalks in the two locations.
El-Gharbia
CultivarsTreatments
Control Chlorpyrifos Diazinon Methomyl FenpropathrinMean Mean R%*** Mean R% Mean R% Mean R%
Giza 2 8.67 cd* 5.00abc 42.31 3.33ab 61.54 7.67 b 11.54 3.67b 57.69S.C.10 13.00 a 6.67a 48.72 5.00a 61.54 12.00 a 7.69 6.67a 48.72S.C.13 5.00 f 2.67cd 46.67 1.67b 66.67 4.67 de 6.67 3.33b 33.33S.C.123 6.33 d-f 3.00b-d 52.63 2.67ab 57.89 5.67 de 10.53 2.67b 57.89
T.W.C. 310 8.00 c-e 5.33ab 33.33 3.33ab 58.33 6.67 cd 16.67 4.33b 45.83T.W.C. 321 8.33 cd 4.00b-d 52.00 5.00a 40.00 8.33 bc 0.00 3.33ab 60.00T.W.C. 323 10.00 bc 3.67b-d 63.33 2.67ab 73.33 8.33 bc 16.67 4.67a 53.33T.W.C. 324 11.33 ab 4.67a-c 58.82 3.33ab 70.59 8.67 bc 23.53 5.00b 55.88T.W.C. 351 5.00 f 2.00d 60.00 2.67ab 46.67 4.00 e 20.00 2.33b 53.33T.W.C. 352 5.67 ef 3.00b-d 47.06 2.00b 64.71 4.33 de 23.53 3.00ab 47.06
Mean 8.13 A 4.00C 50.82 3.17D 61.07 7.03 B 13.52 3.90CD 52.05L.S.D (0.05) for pesticides treatments =0.564 for interactions =2.414
El-BehiraGiza 2 7.67 d 6.67b-d 13.04 4.33a-c 43.48 7.00 cd 8.70 7.00c 8.70S.C.10 15.67 bc 10.00a 36.17 6.33ab 59.57 13.00 a 17.02 13.33a 14.89S.C.13 7.00 e 6.33cd 9.52 5.00a-c 28.57 4.67 b-d 33.33 6.33c 9.52S.C.123 5.67 de 5.67d 0.00 3.00c 47.06 4.67 e 17.65 4.00c 29.41
T.W.C. 310 10.33 bc 8.33a-d 19.35 4.00a-c 61.29 6.33 ab 38.71 10.33b 0.00T.W.C. 321 10.67 c 6.00cd 43.75 6.67a 37.50 10.00 bc 6.25 7.33c 31.25T.W.C. 323 12.33 a 7.33a-d 40.54 4.00a-c 67.57 10.00 bc 18.92 7.00c 43.24T.W.C. 324 13.67 a 9.33ab 31.71 6.67a 51.22 13.33 a 2.44 8.00bc 41.46T.W.C. 351 4.67 de 4.33cd 7.14 3.67bc 21.43 4.67 cd 0.00 3.33c 28.57T.W.C. 352 7.67 b 6.33a-c 17.39 5.67a-c 26.09 6.67 de 13.04 7.00c 8.70
Mean 9.53 A 7.03B 26.22 4.93C 48.25 8.03 A 15.73 7.37B 22.73L.S.D (0.05) for pesticides treatments =1.206 for interactions =2.819
**Average data Giza 2 8.17 de 5.83b-d 28.57 3.83b-d 53.06 7.33 c 10.20 5.33cd 34.69S.C.10 14.33 a 8.33a 41.86 5.67ab 60.47 12.50 a 12.79 10.00a 30.23S.C.13 6.00 f 4.50d 25.00 3.33cd 44.44 4.67 d 22.22 4.83cd 19.44S.C.123 6.00 f 4.33d 27.78 2.83d 52.78 5.17 d 13.89 3.33d 44.44
T.W.C. 310 9.17 d 6.83a-c 25.45 3.67cd 60.00 6.50 c 29.09 7.33b 20.00T.W.C. 321 9.50 cd 5.00cd 47.37 5.83a 38.60 9.17 bc 3.51 5.33cd 43.86T.W.C. 323 11.17 bc 5.50b-d 50.75 3.33cd 70.15 9.17 bc 17.91 5.83b-d 47.76T.W.C. 324 12.50 ab 7.00ab 44.00 5.00a-c 60.00 11.00 b 12.00 6.50bc 48.00T.W.C. 351 4.83 f 3.17d 34.48 3.17cd 34.48 4.33 d 10.34 2.83d 41.38T.W.C. 352 6.67 ef 4.67b-d 30.00 3.83b-d 42.50 5.50 d 17.50 5.00cd 25.00
Mean 8.83 A 5.52C 37.55 4.05D 54.15 7.53 B 14.72 5.63C 36.23L.S.D (0.05) for pesticides treatments =0.565 for interactions =1.926
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars.***R%= ( control-treatment)/ control×100
120 RESULTS AND DISCUSSION
Table IV.22: Efficiency of four chemical insecticides against ECB infestation on ten corn cultivars evaluated by damage grains% in two locations.
El-Gharbia
CultivarsTreatments
Control Chlorpyrifos Diazinon Methomyl FenpropathrinMean Mean R%*** Mean R% Mean R% Mean R%
Mean 5.54A 3.37C 39.18 2.49D 55.16 4.34B 21.67 3.28C 40.83L.S.D (0.05) for pesticides treatments =0.2054 for interactions=0.6886
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars. ***R%= ( control-treatment)/ control×100
121 RESULTS AND DISCUSSION
Table IV.23: Effect of chemical insecticides treatments and corn cultivars on grains protein percentage.
El-Gharbia
CultivarsTreatments
Control Chlorpyrifos Diazinon Methomyl FenpropathrinGiza 2 3.96 b 4.02 b 4.10 bc 3.96 b 4.02 bS.C.10 3.33 de 3.36 d 3.49 ef 3.30 e 3.45 deS.C.13 3.27 ef 3.39 d 3.41 f 3.32 de 3.40 eS.C.123 4.50 a 4.59 a 4.55 a 4.49 a 4.59 a
T.W.C. 310 3.83 bc 3.95 b 3.87 cd 3.71 bc 4.05 bT.W.C. 321 3.08 ef 3.25 d 3.30 f 3.08 e 3.30 eT.W.C. 323 3.04 f 3.21 d 3.37 f 3.10 e 3.28 eT.W.C. 324 3.58 cd 3.66 c 3.70 de 3.57 cd 3.68 cdT.W.C. 351 4.02 b 3.97 b 4.14 b 3.90 b 4.11 bT.W.C. 352 3.76 bc 3.81 bc 3.84 cd 3.79 bc 3.90 bc
Mean 3.64 BC 3.72 AB 3.78 A 3.62 C 3.78 AL.S.D (0.05) for pesticides treatments =0.09784 for interactions=0.2625
El-BehiraGiza 2 4.17 a 4.15 a 4.23 ab 3.67 bc 4.26 aS.C.10 3.28 c 3.46 cd 3.45 d 3.24 e 3.30 dS.C.13 3.22 c 3.42 cde 3.41 d 3.28 de 3.39 cdS.C.123 4.31 a 4.35 a 4.46 a 4.35 a 4.43 a
T.W.C. 310 3.71 b 3.87 b 3.99 bc 3.67 bc 3.94 bT.W.C. 321 3.24 c 3.25 de 3.35 d 3.08 e 3.22 dT.W.C. 323 3.05 c 3.17 e 3.32 d 3.15 e 3.37 cdT.W.C. 324 3.57 b 3.58 bc 3.88 c 3.52 cd 3.61 cT.W.C. 351 3.81 b 3.80 b 3.99 bc 3.84 b 3.91 bT.W.C. 352 3.61 b 3.69 bc 3.73 c 3.61 bc 3.62 c
Mean 3.60 A 3.67 A 3.78 A 3.54 A 3.71 AL.S.D (0.05) for pesticides treatments =0.2831 for interactions=0.2675
Average data**Giza 2 4.06 b 4.09 b 4.16 b 3.81 b 4.14 bS.C.10 3.31 e 3.41 ef 3.47 e 3.27 de 3.38 dS.C.13 3.25 ef 3.40 fg 3.41 e 3.30 d 3.39 dS.C.123 4.41 a 4.47 a 4.50 a 4.42 a 4.51 a
T.W.C. 310 3.77 cd 3.91 bc 3.93 cd 3.69 bc 4.00 bT.W.C. 321 3.16 ef 3.25 fg 3.33 e 3.08 e 3.26 dT.W.C. 323 3.04 f 3.19 g 3.35 e 3.12 de 3.32 dT.W.C. 324 3.57 d 3.62 de 3.79 d 3.54 c 3.65 cT.W.C. 351 3.92 bc 3.89 bc 4.07 bc 3.87 b 4.01 bT.W.C. 352 3.68 d 3.75 cd 3.79 d 3.70 bc 3.76 c
Mean 3.62 BC 3.70 AB 3.78 A 3.58 C 3.74 AL.S.D (0.05) for pesticides treatments =0.09414 for interactions=0.2122
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars.
122 RESULTS AND DISCUSSION
Table IV.24: Effect of chemical insecticides treatments and corn cultivars on grains phosphors percentage.
El-Gharbia
CultivarsTreatments
Control Chlorpyrifos Diazinon Methomyl FenpropathrinGiza 2 0.48 ab 0.52a 0.48ab 0.46 ab 0.53aS.C.10 0.49 a 0.52a 0.52a 0.50 a 0.49abS.C.13 0.43 bc 0.42b 0.44b 0.42 bc 0.43cdS.C.123 0.50 a 0.50a 0.50a 0.51 a 0.50ab
T.W.C. 310 0.35 d 0.34c 0.32c 0.35 de 0.38deT.W.C. 321 0.48 ab 0.48a 0.48ab 0.48 a 0.47bcT.W.C. 323 0.37 d 0.41b 0.37c 0.39 cd 0.37eT.W.C. 324 0.40 cd 0.34c 0.35c 0.33 e 0.34eT.W.C. 351 0.50 a 0.49a 0.51a 0.49 a 0.52abT.W.C. 352 0.51 a 0.51a 0.53a 0.50 a 0.50ab
Mean 0.45 A 0.45A 0.45A 0.44 A 0.45AL.S.D (0.05) for pesticides treatments =0.0010 for interactions=0.05147
El-BehiraGiza 2 0.49 a 0.50ab 0.52a 0.52 a 0.50aS.C.10 0.50 a 0.49ab 0.51a 0.51 a 0.51aS.C.13 0.42 bc 0.42cd 0.45bc 0.42 c 0.43bcS.C.123 0.49 a 0.51a 0.49ab 0.49 ab 0.50a
T.W.C. 310 0.35 de 0.34e 0.35de 0.35 d 0.38cT.W.C. 321 0.47 ab 0.45bc 0.48ab 0.44 bc 0.47abT.W.C. 323 0.40 cd 0.38de 0.40cd 0.41 c 0.39cT.W.C. 324 0.34 e 0.34e 0.33e 0.34 d 0.32dT.W.C. 351 0.52 a 0.54a 0.51a 0.53 a 0.49aT.W.C. 352 0.50 a 0.50ab 0.51a 0.50 a 0.47ab
Mean 0.45 A 0.45A 0.45A 0.45 A 0.45AL.S.D (0.05) for pesticides treatments =0.0059 for interactions=0.05147
Avareg data**Giza 2 0.49 bc 0.51a 0.50bc 0.49 b 0.52aS.C.10 0.50 ab 0.51a 0.52a 0.51 a 0.50bS.C.13 0.42 d 0.42c 0.44e 0.42 d 0.43dS.C.123 0.50 ab 0.51a 0.49cd 0.50 ab 0.50b
T.W.C. 310 0.35 f 0.34e 0.34g 0.35 f 0.38eT.W.C. 321 0.48 c 0.46b 0.48d 0.46 c 0.47cT.W.C. 323 0.38 e 0.40d 0.39 f 0.40 e 0.38eT.W.C. 324 0.37 e 0.34e 0.34g 0.33 g 0.33 fT.W.C. 351 0.51 a 0.51a 0.51ab 0.51 a 0.50bT.W.C. 352 0.51 a 0.50a 0.52a 0.50 ab 0.48c
Mean 0.45 A 0.45A 0.45A 0.45 A 0.45AL.S.D (0.05) for pesticides treatments =0.0059 for interactions=0.01628
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars.
123 RESULTS AND DISCUSSION
Table IV.25: Effect of chemical insecticides treatments and corn cultivars on 100 grains weight (g.).
El-Gharbia
CultivarsTreatments
Control Chlorpyrifos Diazinon Methomyl FenpropathrinGiza 2 28.99*ab 29.81 a 29.70 a-c 27.63ab 29.63 bS.C.10 31.44a 31.36 a 32.79 a 30.08a 30.81 aS.C.13 23.00c 28.18 ab 28.09 bc 25.76bc 27.79 bS.C.123 26.00bc 27.64 ab 27.63 bc 27.68ab 27.00 b
T.W.C. 310 29.48ab 29.25 ab 29.25 a-c 27.47ab 28.70 bT.W.C. 321 29.55ab 25.58 b 31.29 ab 29.53ab 29.17 abT.W.C. 323 25.69bc 25.65 b 26.16 c 23.12c 25.21 aT.W.C. 324 28.74ab 31.18 a 30.86 ab 28.53ab 28.62 bT.W.C. 351 27.93b 28.42 ab 29.81 a-c 26.53a-c 27.44 bT.W.C. 352 27.73ab 28.58 ab 27.54 bc 25.88bc 28.08 ab
Mean 27.86AB 28.57 AB 29.31 A 27.22B 28.24 CDL.S.D (0.05) for pesticides treatments =1.659 for interactions=3.894
El-BehiraGiza 2 31.04 d 32.29 ef 33.42 d 30.33e 31.41 ghS.C.10 35.34 bc 37.11 a 38.99 a 37.03a 37.93 abS.C.13 35.04 e 36.23 ab 36.24 bc 31.54de 38.30 aS.C.123 32.77 de 34.57 b-d 34.65 cd 32.68cd 32.55 e-g
T.W.C. 310 33.60 bc 35.72 a-c 33.82 d 34.27bc 34.44 c-eT.W.C. 321 30.97 c 34.01 c-e 33.94 d 31.24de 32.06 f-hT.W.C. 323 31.96 a 33.76 de 33.90 d 32.45cd 33.66 d-fT.W.C. 324 33.20 a 35.80 a-c 37.39 ab 34.13bc 34.47 cdT.W.C. 351 30.82 de 31.02 f 30.94 e 30.36e 30.34 hT.W.C. 352 36.68 b 36.31 ab 37.33 ab 36.02ab 36.15 bc
Mean 33.14 A 34.68 AB 35.06 A 33.01C 34.13 BL.S.D (0.05) for pesticides treatments =1.085 for interactions=1.914
Avarage data**Giza 2 30.02c-e 31.05 bc 31.56 c-e 28.98c-e 30.52 c-eS.C.10 33.39a 34.24 a 35.89 a 33.56a 34.37 aS.C.13 29.02de 32.21 ab 32.16 b-d 28.65de 33.04 abS.C.123 29.39de 31.11 bc 31.14 c-e 30.18b-d 29.78 de
T.W.C. 310 31.54a-c 32.48 ab 31.53 c-e 30.87bc 31.57 b-dT.W.C. 321 30.26b-e 29.80 c 32.61 bc 30.38b-d 30.62 c-eT.W.C. 323 28.83e 29.71 c 30.03 e 27.79e 29.43 eT.W.C. 324 30.97b-d 33.49 a 34.12 ab 31.33b 31.55 b-dT.W.C. 351 29.37e 29.72 c 30.38 de 28.44de 28.89 eT.W.C. 352 32.21ab 32.44 ab 32.44 bc 30.95bc 32.11 bc
Mean 30.50BC 31.62 A 32.19 A 30.11C 31.19 ABL.S.D (0.05) for pesticides treatments =0.9383 for interactions=2.032
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars.
124 RESULTS AND DISCUSSION
Table IV.26: Effect of chemical insecticides treatments and corn cultivars on grains yield/10plants (kg.).
El-Gharbia
CultivarsTreatments
Control Chlorpyrifos Diazinon Methomyl FenpropathrinGiza 2 1.26a* 1.44 b-d 1.62 b-d 1.43ab 1.59 bS.C.10 1.51a 1.87 a 2.02 a 1.52a 1.66 aS.C.13 1.05bc 1.40 cd 1.29 de 1.22a 1.38 bS.C.123 1.46a 1.77 ab 1.91 ab 1.47a 1.60 b
T.W.C. 310 1.16a-c 1.46 d 1.46 c-e 1.32a 1.40 abT.W.C. 321 1.38ab 1.63 a-c 1.77 a-c 1.45a 1.51 bT.W.C. 323 0.97c 1.20 d 1.24 e 0.98b 1.08 aT.W.C. 324 1.47a 1.92 a 2.00 a 1.48a 1.64 bT.W.C. 351 1.37ab 1.59 a-c 1.68 a-c 1.35a 1.52 bT.W.C. 352 1.30a-c 1.48 b-d 1.77 a-c 1.54a 1.58 ab
Mean 1.29C 1.58 B 1.68 A 1.38C 1.50 CDL.S.D (0.05) for pesticides treatments =0.1427 for interactions=0.3687
El-BehiraGiza 2 1.37d 1.66 a 1.69 a-c 1.38a-c 1.54 abS.C.10 1.42bc 1.65 a 1.80 ab 1.47a 1.66 aS.C.13 1.18e 1.35 b 1.58 bc 1.19d 1.51 a-cS.C.123 1.22de 1.59 ab 1.47 cd 1.31a-d 1.36 bc
T.W.C. 310 1.24c 1.61 ab 1.66 a-c 1.25b-d 1.41 a-cT.W.C. 321 1.44bc 1.66 a 1.72 a-c 1.45ab 1.59 a-cT.W.C. 323 1.05a 1.50 ab 1.28 d 1.11cd 1.23 cT.W.C. 324 1.47a 1.69 a 1.88 a 1.50a 1.62 abT.W.C. 351 1.30b 1.42 ab 1.52 cd 1.33b-d 1.47 a-cT.W.C. 352 1.35de 1.42 ab 1.63 cd 1.30a-d 1.42 bc
Mean 1.30A 1.55 A 1.62 A 1.33C 1.48 BL.S.D (0.05) for pesticides treatments =0.09641 for interactions=0.2828
Average data**Giza 2 1.31ab 1.55 b-e 1.66 bc 1.41a 1.57 aS.C.10 1.47a 1.76 ab 1.91 a 1.50a 1.66 aS.C.13 1.11cd 1.37 e 1.44 cd 1.21ab 1.44 aS.C.123 1.34a-c 1.68 a-c 1.69 a-c 1.39a 1.48 a
T.W.C. 310 1.20b-d 1.54 de 1.56 bc 1.28ab 1.41 abT.W.C. 321 1.41ab 1.64 a-d 1.74 ab 1.45a 1.55 aT.W.C. 323 1.01d 1.35 e 1.26 d 1.05b 1.15 bT.W.C. 324 1.47a 1.81 a 1.94 a 1.49a 1.63 aT.W.C. 351 1.34a-c 1.51 c-e 1.60 bc 1.34ab 1.50 aT.W.C. 352 1.33a-c 1.45 c-e 1.70 bc 1.42a 1.50 a
Mean 1.30D 1.57 B 1.65 A 1.35D 1.49 CL.S.D (0.05) for pesticides treatments =0.08857 for interactions=0.1289
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of location factor the table reflect tolerance of different cultivars.
125 RESULTS AND DISCUSSION
IV.4 Chemical analysis of Corn cultivars.
The aim of this investigation is identify the mechanisms of resistance in
previous corn cultivars through determination of some chemical and physical
parameters ( cellulose contents , percent of ash , total soluble solid TSS and stem
Rigidity). The present investigation was conducted at the experimental farm of
Faculty of Agriculture, University of Tanta. The experiments were made in 2003
growing seasons. The experimental design was a factorial complete randomized
plot with three replications and 10 treatments (the previous cultivers).
Table(IV.27) show the chemical and physical parameters of the previous
corn cultivars.
Cultivars S.C.123 and Giza 2 had the lowest values in ash% (6.89 and
6.92 respectively) while, T.W.C. 352 and T.W.C. 324 cultivars had the highest
value in this respect ( 7.59 and 7.28 respectively).
Cultivars S.C.10, T.W.C. 352 and T.W.C. 351 had the highest values in
%Celluloses (34.73, 31.63 and 31.57 respectively). On the other hand Giza 2 and
T.W.C. 323 cultivars had the lowest value in this regard ( 22.93 and 24.20
respectively).
Cultivars T.W.C. 351 and S.C.13 had the lowest values in TSS ( 3.63 and
3.73 respectively) while, T.W.C. 321,T.W.C. 324, T.W.C. 352 and T.W.C. 323 had
the highest value in this respect ( 5.47,5.27, 5.20 and 5.20 respectively).
Cultivars S.C.13, T.W.C. 352 and S.C.123 had the lowest values in stem
rigidity which had 2.93, 3.00 and 3.00 Newton, while S.C.10 and T.W.C. 323 had
the highest values in this respect which had 5.38 and 4.83 Newton respectively.
126 RESULTS AND DISCUSSION
Table IV.27: Some chemical and physical parameters of ten corn cultivars.
Cultivars Chemical parameters Physical parameters
%Ash %Celluloses TSS Rigidity
Giza 2 6.92 22.93 4.13 3.11
S.C.10 6.95 34.73 4.60 5.38
S.C.13 6.97 26.97 3.73 2.93
S.C.123 6.89 27.08 4.33 3.00
T.W.C. 310 7.24 30.89 4.73 4.37
T.W.C. 321 7.31 26.17 5.47 4.35
T.W.C. 323 7.16 24.20 5.27 4.83
T.W.C. 324 7.28 25.01 5.20 4.36
T.W.C. 351 7.19 31.57 3.63 3.84
T.W.C. 352 7.59 31.63 5.20 3.00
127 RESULTS AND DISCUSSION
IV.5 Evaluation of some microbial insecticides efficiency against ECB on certain maize cultivators compared with chemical insecticides under natural infestation conditions.Two field experiment were carried out at the Experimental Farm of Faculty
of Agric., Tanta Univ. during 2004 and 2005 successive seasons. To evaluate some
biocide (Agrine and Biofly), mixtures of biocides with some protective agents (oil
and photostaplizer which enhanced the bioicide persistence against sunlight and
UV) and bioicide mixtures with protective agents and the half the field application
rate of diazinon (the most efficient insecticide). That on the most tolerant corn
cultivar and two of the highest production caltivars and also hight susceptible to
ECB infestation . To achieve the most integrated chemical & biological control of
the European Corn Borer (Ostrinia nubilalis).
IV.5.1 Holes No./100 internodes. Data presented in Table (IV.28) show the effect of bioicide treatments
and corn cultivars on ECB infestation assessed by holes No./100 internodes.
A significant differences among corn cultivars and biocides treatments
were detected in the two seasons.
At season 2004: cultiver S.C. 10 treated with mixture No.4 or diazinon
treatments had the lowest value in holes No./100 internodes.
Holes No./100 internodes values of S.C.10 cultiver treated with biocides
were in ascending order as follows:Diazinon< mixture No.4< mixture No.3<
S.C10 cultivar had surpassed the other cultivars T.W.C.310 and T.W.C.351
in grains yield /10plants .
From the previous data it could be concluded that:
● In case of infestation parameter (holes No./100internodes and
cavities No./10plants, ) it could be concluded that: In all cultivars (S.C.10,
T.W.C.310 and T.W.C351) control, paraffin oil and Agerin treatments had
the highest values in this parameters, while diazinon, mixture No.4 and
mixture No.3 had the lowest values in this regard but the ranke between
them differ from cultivar to anther. The cultivars rank in this parameters
had S.C10, T.W.C310 and T.W.C351.
● In case of productivity parameters (100 grains weight and grains
yield/10plants), the trend differ from parameters to another. But, it could be
concluded that:
● In case of 100 grain weight: control, paraffin oil and Agerin
treatments had the lowest values in this respect, while diazinon, mixture
No.4 and mixture No.3 had the highest values, either But, the cultivars
rank of in these parameters were S.C10, T.W.C310, and T.W.C351.
● In case of grains yield/10plants: control, paraffin oil and Agerin
treatments had the lowest values in this respect, while diazinon, mixture
No.3, mixture No.2 and mixture No.4 had the highest values٫ But, the
138 RESULTS AND DISCUSSION
cultivars rank of these parameters were S.C10, T.W.C310, and T.W.C351.
Generally:
● There are no significant differences between control and paraffin
oil treatments in most studied parameters.
● Agrine was the lowest effective treatments against ECB infestation.
● Biofly had a moderate effect in this respect and superior Agrine.
● Mixing Biofly or Agrine with oil and photostablizer had enhanced
the activity of the compounds but was more effective in case of Biofly
Beauveria bassiana.
● Adding the half dose of the pesticides diazinon had enhanced the
activity against ECB infestation and there are no significant difference
between the mixture and the original pesticide in activity in most cases.
● Diazinon, mixture No.4 and mixture No.3 the only treatments that
effecting the stalk holes No/10plants. The most susceptible cultivars in this
respect was S.C.10
● The most susceptibility cultivars was S.C.10 followed by
T.W.C.310 (when take all parameters in consideration).
● S.C.10 had superior other cultivars in all productivity parameters
Many investigators reported that Bacillus thuringiensis had a low efficacy
against ECB infestation. Also, Beauveria bassina formulation had superior
Bacillus thuringiensis formulation in activity against ECB infestation (Sabbour,
2002; Cagan et al., 1995; Chiuo and Hou,1993 and Lewis and Bing, 1991). On
the other hand, our finding disagree with, He, et al.(2002) who, found that
Bacillus thuringiensis (B.t) spray and B.t granules were more effective than
Beauveria bassiana formulation in reducing the damage from ACB on sweet corn.
139 RESULTS AND DISCUSSION
Table IV.28: Efficiency of biocides treatments against ECB infestation on three corn cultivars evaluated by holes number/100 internodes, during 2004 and 2005 seasons.
Season 2004
TreatmentsCultivars
S.C. 10 T.W.C. 310 T.W.C 351Means
Mean % R.*** Mean % R. Mean % R. Mean % R.Control 20.09 a 16.80 a 15.45 a 17.45 a
Paraffin oil 19.53 a 2.80 17.25 a -2.68 15.48 a -0.19 17.42 a 0.15Agerin 13.28 b 33.90 12.48 b 25.69 12.05 b 22.01 12.60 b 27.76Biofly 10.30 c 48.72 7.67 c 54.34 7.56 c 51.08 8.51 c 51.22
Mixture No. 1 7.59 d 62.23 7.90 c 52.95 6.76 c 56.28 7.41 cd 57.50Mixture No. 2 5.25 de 73.85 7.05 cd 58.03 5.93 cd 61.59 6.08 de 65.15Mixture No. 3 3.24 ef 83.86 4.64 de 72.36 5.13 cde 66.83 4.34 ef 75.14Mixture No. 4 2.13 f 89.38 3.90 e 76.79 3.02 e 80.48 3.02 f 82.72
Diazinon 2.07 f 89.67 4.36 de 74.03 4.04 de 73.88 3.49 f 79.99Means 9.28 A 9.12 A 8.38 A 8.92
L.S.D (0.05) for cultivars treatments=1.976 for biocides treatments=1.981 for interactions=2.711Season 2005
Control 14.37 a 10.52 a 9.29 a 11.39 aParaffin oil 14.56 a -1.32 9.42 ab 10.49 8.55 a 8.01 10.84 a 4.85
Agerin 9.18 b 36.11 8.19 bc 22.18 5.31 b 42.82 7.56 b 33.65Biofly 2.84 d 80.21 4.50 e 57.27 5.09 b 45.17 4.14 cd 63.63
Mixture No. 1 9.55 b 33.52 6.83 cd 35.07 5.80 b 37.61 7.39 b 35.11Mixture No. 2 5.58 c 61.20 5.40 de 48.62 3.87 bc 58.34 4.95 c 56.55Mixture No. 3 4.90 cd 65.93 1.63 g 84.52 1.92 cd 79.29 2.82 de 75.29Mixture No. 4 3.44 cd 76.08 2.64 f 74.89 1.29 d 86.16 2.46 e 78.45
Diazinon 3.30 d 77.05 1.22 g 88.42 2.62 cd 71.79 2.38 e 79.12Means 7.52 A 5.59 B 4.86 B 5.99
L.S.D (0.05) for cultivars treatments=0.8803 for biocidestreatments=1.511 for interactions=2.271**Averaged data
Control 17.23 a 13.66 a 12.37 a 14.42 aParaffin oil 17.04 a 1.08 13.33 a 2.39 12.01 a 2.89 14.13 a 2.01
Agerin 11.23 b 34.83 10.33 b 24.34 8.68 b 29.82 10.08 b 30.08Biofly 6.57 d 61.85 6.08 c 55.47 6.33 c 48.86 6.33 cd 56.12
Mixture No. 1 8.57 c 50.26 7.37 c 46.06 6.28 c 49.27 7.40 c 48.65Mixture No. 2 5.41 de 68.57 6.23 c 54.41 4.90 cd 60.37 5.51 d 61.76Mixture No. 3 4.07 ef 76.39 3.14 d 77.04 3.53 de 71.51 3.58 e 75.20Mixture No. 4 2.79 f 83.83 3.27 d 76.06 2.15 e 82.61 2.74 e 81.03
Diazinon 2.69 f 84.41 2.79 d 79.57 3.33 de 73.09 2.94 e 79.65Means 8.40 A 7.35 AB 6.62 B 7.46
L.S.D (0.05) for cultivars treatments=1.205 for biocidestreatments=1.636 for interactions=1.755
**Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of seasons factor the table reflect efficacy of different biocides. ***R%= (control -treatment-)/ control×100
140 RESULTS AND DISCUSSION
Table IV.29: Efficiency of biocides treatments against ECB infestation on three corn cultivars evaluated by cavity number/10 plants, during 2004 and 2005 seasons.
Season 2004
TreatmentsCultivars
S.C. 10 T.W.C. 310 T.W.C 351Means
Mean % R.*** Mean % R. Mean % R. Mean % R.Control 27.00 a* 21.67 a 18.00 a 22.22 a
Paraffin oil 27.70 a -2.61 23.33 a -7.69 18.33 a -1.85 23.12 a -4.06Agerin 17.33 b 35.80 16.67 b 23.08 14.00 b 22.22 16.00 b 28.00Biofly 14.07 b 47.87 9.00 c 58.46 8.33 c 53.70 10.47 c 52.89
Mixture No. 1 9.67 c 64.20 10.67 c 50.77 7.93 c 55.97 9.42 cd 57.61Mixture No. 2 6.30 cd 76.68 8.67 c 60.00 6.67 cd 62.96 7.21 de 67.56Mixture No. 3 4.59 d 82.99 4.48 d 79.32 5.00 cde 72.22 4.69 ef 78.89Mixture No. 4 2.67 d 90.12 3.67 d 83.08 2.33 e 87.04 2.89 f 87.00
Diazinon 2.66 d 90.16 4.67 d 78.46 4.00 de 77.78 3.77 f 83.01Means 12.44 A 11.42 A 9.40 B 11.09
L.S.D (0.05) for cultivars treatments=1.912 for biocides treatments=2.737 for interactions=3.900Season 2005
Control 22.67 a 13.04 ab 13.33 a 16.35 aParaffin oil 18.67 b 17.65 15.33 a -17.61 10.33 ab 22.50 13.44 b 17.75
Agerin 14.33 c 36.76 11.33 b 13.07 9.00 bc 32.50 12.89 b 21.15Biofly 5.00 e 77.94 5.33 de 59.09 7.26 bcd 45.56 5.86 de 64.12
Mixture No. 1 14.00 c 38.24 10.67 bc 18.18 6.26 cd 53.06 10.31 c 36.93Mixture No. 2 9.67 d 57.35 7.67 cd 41.19 4.67 de 65.00 7.33 d 55.14Mixture No. 3 9.00 d 60.29 2.33 e 82.10 2.00 e 85.00 4.44 ef 72.81Mixture No. 4 5.33 e 76.47 3.33 e 74.43 2.00 e 85.00 3.56 ef 78.25
Diazinon 4.67 e 79.41 1.33 f 89.77 4.33 de 67.50 3.44 f 78.93Means 11.48 A 7.82 B 6.58 B 8.63
L.S.D (0.05) for cultivars treatments=1.352 for biocides treatments=2.386 for interactions=3.567**Averaged data
Control 24.83 a 17.35 b 15.67 a 19.28 aParaffin oil 23.19 a 6.64 19.33 a 0.11 14.33 a 8.51 18.28 a 5.19
Agerin 15.83 b 36.24 14.00 c 7.79 11.50 b 26.60 14.44 b 25.10Biofly 9.54 cd 61.60 7.17 d 58.70 7.80 c 50.24 8.17 cd 57.65
Mixture No. 1 11.83 c 52.35 10.67 c 38.53 7.09 c 54.73 9.86 c 48.85Mixture No. 2 7.98 de 67.86 8.17 d 52.93 5.67 cd 63.83 7.27 d 62.29Mixture No. 3 6.80 e 72.63 3.41 f 80.36 3.50 de 77.66 4.57 e 76.31Mixture No. 4 4.00 f 83.89 3.50 f 79.83 2.17 e 86.17 3.22 e 83.29
Diazinon 3.66 f 85.25 3.00 f 82.71 4.17 de 73.40 3.61 e 81.28Means 11.96 A 9.62 B 7.99 C 9.86
L.S.D (0.05) for cultivars treatments=1.171 for biocides treatments=2.212 for interactions=2.577
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of seasons factor the table reflect efficacy of different biocides. ***R%= (control -treatment-)/ control×100
141 RESULTS AND DISCUSSION
Table IV.30: Efficiency of biocides treatments against ECB infestation on three corn cultivars evaluated by larvae No./10 plants, during 2004 and 2005 seasons.
Season 2004
TreatmentsCultivars
S.C. 10 T.W.C. 310 T.W.C 351Means
Mean % R.*** Mean % R. Mean % R. Mean % R.Control 15.33 a* 10.33 a 13.67 a 13.11 a
Paraffin oil 15.19 a 0.97 10.00 ab 3.23 13.00 a 4.88 12.73 a 2.92Agerin 11.33 b 26.09 7.33 bc 29.03 9.33 b 31.71 9.33 b 28.81Biofly 7.85 c 48.79 5.67 cd 45.16 5.00 cd 63.41 6.17 c 52.92
Mixture No. 1 5.00 cd 67.39 7.00 c 32.26 5.85 c 57.18 5.95 c 54.61Mixture No. 2 4.07 de 73.43 5.67 cd 45.16 5.33 cd 60.98 5.02 cd 61.68Mixture No. 3 2.85 de 81.40 3.11 de 69.89 4.00 cde 70.73 3.32 de 74.67Mixture No. 4 2.00 e 86.96 2.67 e 74.19 1.67 e 87.80 2.11 e 83.90
Diazinon 2.61 de 82.97 3.67 de 64.52 2.67 de 80.49 2.98 e 77.26Means 7.36 A 6.16 A 6.72 A 6.75
L.S.D (0.05) for cultivars treatments=1.330 for biocides treatments=1.843 for interactions=2.881Season 2005
Control 11.00 a 7.26 a 8.67 a 8.98 aParaffin oil 9.67 ab 12.12 6.33 a 12.76 8.33 a 3.85 8.00 ab 10.87
Agerin 8.67 ab 21.21 6.00 ab 17.35 4.67 bc 46.15 6.56 bc 26.96Biofly 4.00 de 63.64 3.00 cd 58.67 3.07 bcde 64.53 3.36 ef 62.59
Mixture No. 1 8.00 bc 27.27 5.67 ab 21.94 4.19 bcd 51.71 5.95 cd 33.70Mixture No. 2 5.67 cd 48.48 3.67 bc 49.49 5.00 b 42.31 4.78 de 46.77Mixture No. 3 4.00 de 63.64 1.33 cd 81.63 1.67 e 80.77 2.33 f 74.00Mixture No. 4 2.00 e 81.82 2.33 cd 67.86 2.00 de 76.92 2.11 f 76.48
Diazinon 2.67 e 75.76 1.00 d 86.22 2.33 cde 73.08 2.00 f 77.72Means 6.19 A 4.07 B 4.44 B 4.90
L.S.D (0.05) for cultivars treatments=1.287 for biocides treatments=1.482 for interactions=2.352**Averaged data
Control 13.17 a 8.80 a 11.17 a 11.04 aParaffin oil 12.43 a 5.63 8.15 ab 9.05 10.67 a 4.48 10.36 a 6.15
Agerin 10.00 b 24.05 6.67 b 22.32 7.00 b 37.31 7.94 b 28.06Biofly 5.93 c 54.99 4.33 de 50.74 4.04 cd 63.85 4.77 c 56.85
Mixture No. 1 6.50 c 50.63 6.33 bc 28.00 5.02 c 55.06 5.95 c 46.12Mixture No. 2 4.87 cd 63.01 4.67 d 46.95 5.17 bc 53.73 4.90 c 55.62Mixture No. 3 3.43 de 73.98 2.22 f 74.74 2.83 de 74.63 2.83 d 74.40Mixture No. 4 2.00 e 84.81 2.50 ef 71.58 1.83 e 83.58 2.11 d 80.88
Diazinon 2.64 e 79.96 2.33 f 73.47 2.50 de 77.61 2.49 d 77.45Means 6.77 A 5.11 B 5.58 B 5.82
L.S.D (0.05) for cultivars treatments=0.8611 for biocides treatments=1.341 for interactions=1.896
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of seasons factor the table reflect efficacy of different biocides. ***R%= (control -treatment-)/ control×100
142 RESULTS AND DISCUSSION
Table IV.31: Effect of biocides treatments and corn cultivars on 100 grain weight(g.), during 2004 and 2005 seasons.
Season 2004
TreatmentsCultivars
S.C. 10 T.W.C. 310 T.W.C 351Mean Mean Mean
Means
Control 29.69 d* 28.56 a 28.30 a 28.85 cParaffin oil 30.38 cd 28.23 a 27.63 a 28.75 c
Agerin 30.36 cd 28.96 a 27.80 a 29.04 bcBiofly 31.71 bcd 28.92 a 27.70 a 29.44 bc
Mixture No. 1 31.81 bcd 29.61 a 27.45 a 29.62 bcMixture No. 2 31.52 bcd 29.09 a 27.60 a 29.41 bcMixture No. 3 32.12 bc 29.32 a 28.28 a 29.91 bcMixture No. 4 32.84 ab 30.07 a 28.11 a 30.34 ab
Diazinon 34.84 a 30.31 a 29.24 a 31.46 aMeans 31.70 a 29.23 b 28.01 b 29.65
L.S.D (0.05) for cultivars treatments=1.565 for biocides treatments=1.392 for interactions=2.390Season 2005
Control 29.52 c 28.27 ab 27.82 ab 28.54 cParaffin oil 30.67 bc 28.92 ab 26.86 b 28.82 c
Agerin 30.68 bc 28.43 ab 27.07 b 28.73 cBiofly 30.72 bc 28.89 ab 27.60 ab 29.07 bc
Mixture No. 1 31.25 abc 29.16 ab 27.79 ab 29.40 bcMixture No. 2 31.67 abc 29.30 ab 28.19 ab 29.72 abcMixture No. 3 32.05 ab 27.65 b 28.21 ab 29.30 bcMixture No. 4 32.66 ab 30.62 a 28.68 ab 30.66 ab
Diazinon 33.54 a 30.05 ab 29.70 a 31.10 aMeans 31.42 a 29.03 b 27.99 b 29.48
L.S.D (0.05) for cultivars treatments=1.873 for biocides treatments=1.591 for interactions=2.514Averaged data**
Control 29.60 d 28.41 c 28.06 ab 28.69 cParaffin oil 30.53 cd 28.57 bc 27.24 b 28.78 c
Agerin 30.52 cd 28.69 bc 27.44 b 28.88 cBiofly 31.21 bcd 28.90 abc 27.65 b 29.26 c
Mixture No. 1 31.53 bc 29.38 abc 27.62 b 29.51 bcMixture No. 2 31.59 bc 29.20 abc 27.89 ab 29.56 bcMixture No. 3 32.09 bc 28.48 c 28.25 ab 29.60 bcMixture No. 4 32.75 ab 30.34 a 28.40 ab 30.50 ab
Diazinon 34.19 a 30.18 ab 29.47 a 31.28 aMeans 31.56 a 29.13 b 28.00 b 29.56
L.S.D (0.05) for cultivars treatments=1.594 for biocides treatments=1.132 for interactions=1.648
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of seasons factor the table reflect efficacy of different biocides.
143 RESULTS AND DISCUSSION
Table IV.32: Effect of biocides treatments and corn cultivars on grains yield/10plants (kg.), during 2004 and 2005 seasons .
Season 2004
TreatmentsCultivars
S.C. 10 T.W.C. 310 T.W.C 352Means
Mean Mean Mean MeanControl 1.29 c* 1.19 e 1.15 c 1.21 d
Paraffin oil 1.33 c 1.23 de 1.30 bc 1.29 cdAgerin 1.39 bc 1.39 c-e 1.24 c 1.34 cdBiofly 1.60 a-c 1.41 c-e 1.47 a-c 1.50 bc
Mixture No. 1 1.62 a-c 1.54 b-d 1.42 a-c 1.53 bcMixture No. 2 1.72 ab 1.53 b-e 1.33 bc 1.53 bcMixture No. 3 1.74 a 1.71 a-c 1.62 ab 1.69 abMixture No. 4 1.87 a 1.89 a 1.71 a 1.82 a
Diazinon 1.87 a 1.87 ab 1.70 a 1.81 aMeans 1.60 A 1.53 A 1.44 A 1.52
L.S.D (0.05) for cultivars treatments=260.7 for biocidestreatments=233.8 for interactions=340.4Season 2005
Control 1.31 d 1.27 b 1.21 bc 1.26 dParaffin oil 1.37 d 1.24 b 1.20 c 1.27 d
Agerin 1.45 cd 1.35 ab 1.26 a-c 1.35 cdBiofly 1.52 b-d 1.46 ab 1.34 a-c 1.44 b-d
Mixture No. 1 1.52 b-d 1.44 ab 1.48 a-c 1.48 b-dMixture No. 2 1.67 a-d 1.56 ab 1.48 a-c 1.57 a-cMixture No. 3 1.77 a-c 1.55 ab 1.57 a-c 1.63 a-cMixture No. 4 1.87 ab 1.71 a 1.59 ab 1.72 ab
Diazinon 1.96 a 1.71 a 1.63 a 1.77 aMeans 1.60 A 1.48 AB 1.42 B 1.50
L.S.D (0.05) for cultivars treatments=161.1 for biocidestreatments=286.7 for interactions=386.6Averaged data**
Control 1.30 d 1.23 e 1.18 d 1.24 eParaffin oil 1.35 cd 1.24 e 1.25 cd 1.28 e
Agerin 1.42 cd 1.37 de 1.25 cd 1.35 deBiofly 1.56 bc 1.44 c-e 1.41 b-d 1.47 cd
Mixture No. 1 1.57 bc 1.49 cd 1.45 a-c 1.50 b-dMixture No. 2 1.70 ab 1.54 b-d 1.40 b-d 1.55 bcMixture No. 3 1.75 ab 1.63 a-c 1.59 ab 1.66 abMixture No. 4 1.87 a 1.80 a 1.65 ab 1.77 a
Diazinon 1.91 a 1.79 ab 1.67 a 1.79 aMeans 1.60 A 1.50 AB 1.43 B 1.51
L.S.D (0.05) for cultivars treatments=146.9 for biocidestreatments=177.9 for interactions=249.3
*Means followed by the same letter (s) are not significantly difference (P= 0.95 level)** In spite of seasons factor the table reflect efficacy of different biocides.
144 RESULTS AND DISCUSSION
IV.6 The side effect of biochemicals against the predator, Paederus alfierii (Kock).
Surface deposit technique was used to determine the toxicity of the
previous biochemical to the adults of predator, P. alfierii. LC50 values and there
confidence limits are recorded in Table (IV.33).
From the previous data it could be concluded that, Agerin ( Bacillus
thuringiensis formulation), mixture No.1(Agerin mixture with oil) and paraffin oil
exhibited no toxicity against adults of predator, P. alfierii. The toxicity of the rest
biochemicals could be arranged descendingly as follows: mixture No.4 > mixture