-
343
Neem, Azadirachta indica, as a potentialbiopesticide for
controlling the apple snail,Pomacea canaliculata
Siti Noor Hajjar Md Latip1 and Mohd Fahmi Keni2
1Faculty of Plantation and Agrotechnology, University Technology
MARA, 40450 Shah Alam, Selangor, Malaysia. Email:
[email protected] Division, Malaysian Palm Oil
Board (MPOB), No. 6, Persiaran Institusi, Bandar Baru Bangi, 43000
Kajang, Selangor, Malaysia.
Abstract
Experiments were undertaken to assess the efficacy of methanol
and water extractions of fresh neem (Azadirachta indica) seed
against apple snails. Each assay included five neem treatments
(10-50 % dilutions of concentrated extract), a control treatment
and a chemical treatment using Niclosamide. Assays were replicated.
Snail mortality was recorded at 24, 48, 72 and 96 h. There was
little difference between the extracts obtained by methanol and
water extractions. Mortality increased over time and with neem
extract concentration. The highest concentration of neem extract
(50 % dilution) resulted in similar mortality levels to the
Niclosamide treatment. The study showed that fresh neem seed
extract has potential as a botanical pesticide against apple
snails.
Additional keywords: Ampullariidae, botanical pesticide,
Malaysia, Mollusca, neem seed, pest, rice
-
344 BIology and ManageMent of InvasIve apple snaIls
Introduction
The South American apple snail Pomacea canaliculata, listed
among 100 of the world’s most invasive species (Lowe et al., 2000),
was intentionally introduced and cultivated as a protein source in
Taiwan, but rapidly spread to other parts of Asia (Ng & Tan,
2011). It now occurs in most Southeast Asian countries (Hayes et
al., 2008), where it is a serious invasive agricultural pest,
especially in paddy cultivation fields (Cowie, 2002). Several
characteristics may facilitate the snails’ invasive potential
including that it is a food generalist and has a very fast growth
rate and reproduction capacity (Hayes et al., 2015).
Damage to rice plants occurs primarily as a result of the snails
feeding on the young leaf tips within the first 14 days after
transplanting or emergence of the seedlings (Ito, 2002). Older
seedlings with hardened leaves are less vulnerable to attack. In
cases of severe infestation, the snails can cause extensive crop
losses and farmers may even lose their entire crop. The damage
level in the field depends on the size and number of the snails
(Morallo-Rejesus et al., 1989). Naylor (1996) reported that a
density of eight snails/m2 can decrease rice yields by 90 %.
Various strategies are being used by farmers to eradicate or
control the snails, including cultural and mechanical, biological,
chemical and botanical control. Hand picking and crushing of adult
snails and eggs is widely practiced in most rice growing regions in
Asia, including Malaysia. Significant control can be achieved by
hand picking if sufficient labour is available. The efficacy of
hand picking can be improved by using attractants such as leaves of
various plants (Teo, 1999). Other common cultural and mechanical
practices that are still implemented widely include installing
metal screens on irrigation inlets to prevent entry of apple snails
from irrigation canals, maintaining a shallow water depth after
transplanting to suppress snail activities, transplanting seedlings
that are more than 30 days old, dry rotavation and keeping the
fields dry during the off planting season to inhibit breeding (Teo,
1999).
Biological control using fish such as the common carp, Nile
tilapia, black carp and hybrid fish have been experimentally used
to control apple snails in rice fields in the Philippines and
Vietnam with encouraging results. However, field trials of the use
of hybrid catfish in Malaysia have thus far not been so successful
(Jambari & Suryanto, 2000). The use of fish may not be
practical because fish culture requires maintaining relatively
deeper water in the fields (Cowie, 2002).
-
345
Synthetic chemical molluscicides are used extensively in Asia to
control these snails, but it may be costly to both the farmer and
the environment. Niclosamide, metaldehyde, endosulfan, tea seed
cake (residue) and copper sulphate have been used but they are
lethal to non-target organisms and pollute water bodies (Joshi,
2005). For example, Niclosamide, which is the only compound
recommended for control of aquatic snails by the World Health
Organization (WHO), is effective against apple snails at 0.5-1.0 mg
a.i./l, but the LC50 for carp is only 0.14 mg a.i./l (San Martin et
al., 2008). The major environmental concern with these pesticides
is their ability to leach down to the subsoil and contaminate the
ground water, or they may persist on the top soil and become
harmful to microorganisms, plants, animals and people (Tomašević
& Gašić, 2012). Such concerns have led to a focus on isolation
and characterization of natural products that are as effective as
synthetic pesticides without posing the threats to the
environment.
Botanical pesticides are of great interest because they occur
naturally. Historically, plant materials have been in use longer
than any other type of pesticide. The flowers, leaves, bark, seeds
and roots are finely ground and used in this form, or the toxic
ingredients are extracted and used alone or in combination with
other toxicants. Neem (Azadirachta indica) has been recognised for
its pest control properties and is regarded as the most reliable
source of eco-friendly botanical pesticide. In Thailand,
Benchawattananon & Boonkong (2006) compared the toxicity of
crude extracts of neem leaf and garlic (Allium sativum L.); 1000
mg/l of neem killed 96 % of apple snails in 96 hours, while 1000
mg/l of garlic killed 92 % in 96 hours. In Malaysia, showed that
neem leaf extracts killed 93 % of small snails (10-20 mm) and 84 %
of large snails (20-40 mm) after 96 hours in the laboratory
(Massaguni & Latip, 2012).
A major reason for the interest in neem is the widely held view
that neem has numerous valuable attributes, including that it is
safe to both the environment and non-target organisms, and it is
degraded rapidly in the environment. The present study assessed the
efficacy of water and methanol extractions of fresh neem seeds
against apple snails.
Material and methods
Apple snails and neem seed were collected at the Federal Land
Consolidation and Rehabilitation Authority (FELCRA), Seberang,
which is located in the Kampung Gajah Sub-district, Perak,
Malaysia. Ten apple snails in the 20-25 mm size range were selected
for the laboratory study. Neem seed extract was obtained from fresh
neem seeds by
neem, azadirachta Indica, As A Potential BioPesticide For
Controlling The APPle Snail,Pomacea Canaliculata
-
346 BIology and ManageMent of InvasIve apple snaIls
extraction with either methanol or water as the solvent. For the
methanol extraction, the protocol of Parekh et al. (2005) was used,
and for the water extraction that of Polaquini et al. (2006) was
used, both with some modification. In both cases the neem extract
was diluted to concentrations of 100,000 ppm, 200,000 ppm, 300,000
ppm, 400,000 ppm and 500,000 ppm by volume. 1 ml of Tween 20 was
added as an emulsifier in the water dilutions.
Each assay included five neem treatments (100,000 ppm (T1),
200,000 ppm (T2), 300,000 (T3), 400,000 ppm (T4) and 500,000 ppm
(T5), a control treatment and a chemical treatment using
Niclosamide. Each assay was replicated eight times for each of the
water and methanol extractions. Snail mortality was recorded at 24,
48, 72 and 96 h. Snails were considered dead when the body was
contracted within the shell and no response to a needle probe could
be elicited (Singh et al., 1996). Dead snails were removed as soon
as they were found.
The data were analyzed using Minitab 16 and POLO PLUS software.
Analysis of variance (ANOVA) followed by Tukey Simultaneous tests
were performed to assess differences among treatments in overall
mortality after 96 h within each of the assays for methanol and
water extractions. Probit analysis also performed to determine LC50
values (the concentration at which 50 % mortality would occur after
96 h exposure).
Results and discussion
The total percentage mortality differed significantly among
treatments for both extraction protocols (ANOVA: methanol, F =
386.42, P
-
347
Fig.1. Percentage mortality of apple snails treated with
different concentrations of neem extracted in methanol over 96
hours.
Fig.2. Percentage mortality of apple snails treated with
different concentrations of neem extracted in waterover 96
hours.
Das et al. (2010) showed that the duration of each larval stage
of the red slug caterpillar, Eterusia magnifica, lengthened with
increase of neem kernel aqueous extract concentration. And Pinheiro
et al. (2009) reported increased mortality of nymphs of the
silverleaf or sweet potato whitefly, Bemicia tabaci, between three
and five days after application of neem oil and in particular that
neem oil caused mortality to third and fourth instar nymphs after
two days application of treatment.
neem, azadirachta Indica, As A Potential BioPesticide For
Controlling The APPle Snail,Pomacea Canaliculata
-
348 BIology and ManageMent of InvasIve apple snaIls
Probit analysis gave LC50 values for neem extract dilution at 96
h of 26.8 % (95 % confidence interval 22.5-31.8 %) for the methanol
extraction and 24.9 % (95 % confidence interval 20.5-29.8 %) for
the water extraction.
There was little difference in the results for the two
extraction methods with the highest neem seed extract concentration
(50 % dilution) resulting in the highest mortality due to neem,
similar to the level of mortality due to Niclosamide. This study
showed that fresh neem seed extract has potential as a botanical
pesticide against apple snails.
References
Benchawattananon, R. & Boonkong, U. 2006. The toxicity of
leave crude extract from neem tree (Azadirachta indica Juss.) and
garlic (Allium sativom L.) on mortality rate of golden apple snail
(Pomacea sp.), 32nd Congress on Science and Technology of Thailand.
Queen Sirikit National Convention Center, Bangkok, 10-12
October.
Cowie, R.H. 2002. Apple snails as agricultural pests: their
biology, impacts and management. In: Molluscs as Crop Pests
(Barker, G.M., ed.), p. 145-192. CABI Publishing, Wallingford.
Das, R., Chutia, B.C., Sarmah, M. & Rahman, A. 2010. Effect
of neem kernel aqueous extract (NKAE) on growth and development of
red slug caterpillar, Eterusia magnifica Butl in Tea in North-East
India, India. Journal of Biopesticides 3(2): 489-494.
Hayes, K.A., Joshi, R.C., Thiengo, S.C. & Cowie, R.H. 2008.
Out of South America: multiple origins of non-native apple snails
in Asia. Diversity and Distributions 14: 701-712.
Hayes, K.A., Burks, R.L., Castro-Vazquez, A., Darby, P.C.,
Heras, H., Martín, P.R., Qiu, J.-W., Thiengo, S.C., Vega, I.A.,
Wada, T., Yusa, Y., Burela, S., Pilar Cadierno, M., Cueto, J.A.,
Dellagnola, F.A., Dreon, M.S., Frassa, M.V., Giraud-Billoud, M.,
Godoy, M.S., Ituarte, S., Koch, E., Matsukura, K., Pasquevich,
M.Y., Rodriguez, C., Saveanu, L., Seuffert, M.E., Strong, E.E.,
Sun, J., Tamburi, N.E., Tiecher, M.J., Turner, R.L.,
Valentine-Darby, P.L. & Cowie, R.H. 2013. Insights from an
integrated view of the biology of apple snails (Caenogastropoda:
Ampullariidae). Malacologia 58: 245-302.
Ito, K. 2002. Environmental factors influencing overwintering
success of the golden apple snail, Pomacea canaliculata
(Gastropoda: Ampullariidae), in the northernmost population of
Japan. Applied Entomology and Zoology 37(4): 655-661.
-
349
Jambari, A. & Suryanto, E. 2000. Fish as biological control
agent of golden apple snail: prospects and challenges. In:
Biological Control in the Tropics: Towards Efficient Biodiversity
and Bioresource Management for Effective Biological Control.
Proceedings of the Symposium on Biological Control in the Tropics
held at MARDI Training Centre, Serdang, Malaysia from 18-19 March
1999 (Hong, L.W., Sastroutomo, S.S., Caunter, I.G., Ali, J., Yeang,
L.K., Vijaysegaran, S. & Sen, Y.H., ed.), p. 92-95. CABI
Publishing, Wallingford.
Joshi, R.C. 2005. Managing invasive alien mollusc species in
rice. International Rice Research Notes 30: 5-13.
Kudom, A.A.., Mensah, B.A. & Botchey, M.A. 2011. Aqueous
neem extract versus neem powder on Culex quinquefasciatus:
implications for control in anthropogenic habitats. Journal of
Insect Science 11: 142. doi:
http://dx.doi.org/10.1673/031.011.14201.
Lowe, S., Browne, M., Boudjelas, S. & De Poorter, M. 2000.
100 of the World’s Worst Invasive Alien Species. A Selection from
the Global Invasive Species Database. Invasive Species Specialist
Group, Auckland.
Massaguni, R. & Latip, S.N.H.M. 2012. Neem crude extract as
potential biopesticide for controlling golden apple snail, Pomacea
canaliculata. In: Pesticides. Advances in chemical and botanical
pesticides (Soundararajan, R.P., ed.), p. 233-254. InTech, Rijeka,
Croatia.
Morallo-Rejesus, B., Sayaboc, A.S. & Joshi, R.C. 1989. The
distribution and control of the introduced golden snail (Pomacea
spp.) in the Philippines. In: Introduction of Germplasm and Plant
Quarantine Procedures. PLANTI Proceedings No. 4 (Jalil, A.W.,
Manalo, P.L., Sastroutomo, S.S., Ganapathi, A., Chan, K.C., Lim,
L.G., Rahim, M.A.A., Durai, P.S.S. & Stephenson, M.C., ed.), p.
213-223. ASEAN PLANTI, Kuala Lumpur.
Naylor, R. 1996 Invasions in agriculture: assessing the cost of
the golden apple snail in Asia. Ambio 25: 443-448.
Ng, T.H. & Tan, S.K. 2011. Observations of land snails
feeding on the eggs of Pomacea canaliculata (Lamarck, 1822)
(Mollusca: Gastropoda). Nature in Singapore 4: 79-83.
Parekh, J., Jadeja, D. & Chanda, S. 2005. Efficacy of
aqueous and methanol extracts of some medicinal plants for
potential antibacterial activity. Turkish Journal of Biology 29:
203-210.
Pinheiro, P.V., Quintela, E.D., de Oliveira, J.P. &
Seraphin, J.C. 2009. Toxicity of neem oil to Bemisia tabaci biotype
B nymphs reared on dry bean. Pesquisa Agropecuária Brasileira
44(4): 354-360.
neem, azadirachta Indica, As A Potential BioPesticide For
Controlling The APPle Snail,Pomacea Canaliculata
-
350 BIology and ManageMent of InvasIve apple snaIls
Polaquini, S.R.B., Svidzinski, T.I.E., Kemmeimeier, C. &
Gasparetto, A. 2006. Effect of aqueous extract from neem
(Azadirachta indica A. Juss) on hydrophobicity, biofilm formation
and adhesion in composite resin by Candida albicans. Archives of
Oral Biology 51: 482-490.
San Martín, R., Ndjoko, K. & Hostettmann, K. 2008. Novel
molluscicide against Pomacea canaliculata based on quinoa
(Chenopodium quinoa) saponins. Crop Protection 27: 310-319.
Singh, K., Singh, A. & Singh, D.K. 1996. Moluscicidal
activity of neem (Azadirachta indica A. Juss). Journal of
Ethnopharmacology 52: 35-40.
Teo, S.S. 1999. Control of the golden apple snail (Pomacea spp.)
by handpicking using herbage as attractants. In: Sustainable Crop
Protection Practices in the Next Millennium. Proceedings of
MCB-MAPPS Plant Protection Conference ’99. 2-3 November, 1999, Kota
Kinabalu, Sabah, Malaysia (Sidek, Z., Bong, C.L., Kanapathipillai,
V.S., Ong, C.A. & Kadir, H.A., ed), p. 78-81. Malaysian Plant
Protection Society, Kota Kinabalu.
Tomašević, A.V. & Gašić, S.M. 2012. Photoremediation of
carbamate residues in water. In: Insecticides - Basic and Other
Applications (Soloneski, S. & Larramendy, M., ed.), p. 39-60.
InTech, Rijeka, Croatia.