PCP

2010DR. R.K. PANNU DR. SATISH KUMAR DR. S.S. PAHUJA

DEPARTMENT OF AGRONOMY

COLLEGE OF AGRICULTURECHAUDHARY CHARAN SINGH HARYANA AGRICULTURAL UNIVERSITY

HISAR-125004 (HARYANA)

2

FOREWORDI am happy to record that the Practical Crop Production Manual, written by Dr. R. K. Pannu and Dr. Satish Kumar, Department of Agronomy, Chaudhary Charan Singh Haryana Agricultural University (CCSHAU), Hisar, is being published for the benefit of students of agriculture. The manual contains very useful and detailed information on practical aspects of crop production right from land preparation to crop marketing and fulfills the need of a much needed document on practical crop production. It seems to be of great value not only to the students but also to the farmers and other persons engaged in crop production. The authors have rich experience of teaching and research on crop production technology of various field crops and the manual compiled by them will help to solve the practical problems encountered by the persons engaged in production of field crops. The manual is written in simple language and easily understandable as all the practices have been elaborated with solved examples. I hope it will be able to generate the desired confidence in students for solving daily field problems. This publication will certainly make the students to compete for different examinations and to face the interviews with desired vigour and strength. I congratulate the authors for their painstaking efforts in bringing out the manual which in my opinion will meet the demands of the students and other persons concerned directly or indirectly with the cultivation of field crops.

(K.S. Khokhar) Vice-Chancellor CCS Haryana Agricultural University Hisar

PREFACECrop production is the pivot of agriculture. It is a science as well as an art to manage the natural resources in a manner to maintain soil fertility and crop productivity. As, an art it embraces the knowledge to perform the various operations at the farm in a skilful manner. Whereas, the judicious and efficient use of farm resources and inputs for sustainable production is science. Hence, it should be taught to the students in a practical way. In view of the ever-growing human and cattle population and very limited scope for extension of cultivated area, it is necessary to produce more food, feed, fodder, fuel and fiber from the existing land area. But depletion and degradation of natural resources by intensive agriculture in post green revolution era coupled with increasing cost of inputs required for crop production are posing serious threat to sustainability of crop production. Therefore, it requires a comprehensive document of knowledge on different aspects of crop production from planning to marketing to impart practical training to the students. This manual is an attempt to provide knowledge on practical crop production as a cooperative agriculture by group of students. The manual covers all major practical aspects of crop production. The chapters on estimation of crop seed rate, estimation of crop yield, determination of manurial and fertilizer requirements of crops, irrigation and herbicide requirement, preparation of cropping scheme and computing cost of cultivation of crops with solved examples can be used as ready reckner and will develop confidence of self decision. We hope the manual will be helpful in fulfilling the objective of Learning by doing and Earn while you learn. We wish this manual will be useful to the students and teachers alike pursuing the sacred mission of increasing food production for the hungry millions. We are thankful to the authorities of CCS Haryana Agricultural University, Hisar for granting permission to publish this manual. The encouragement and technical help rendered by Dr. A. S. Dhindwal, Professor and Head, Department of Agronomy is thankfully acknowledged. We are extremely thankful to the authors of various books, manuals and documents for getting useful material for inclusion in this publication. We are also grateful to the Indian Council of Agricultural Research for providing financial assistance for publication of this manual. Suggestions for improvement of the subject matter are always welcome. Hisar February, 2010 R. K. Pannu Satish Kumar

S. S. Pahuja

5

CONTENTSSr. No. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. Title Practical crop production programme Seeds its classes, properties, characteristics and calculation Soil fertility and plant nutrition Weeds and their management Dry land agriculture Cropping scheme Irrigation management Package and practices for cultivation of crops Important differences in crop plants Crop terminology Working out cost of cultivation of crops National agricultural insurance scheme Agricultural loaning Land record terminology Annexures Page No. 1-3 4-14 15-31 32-45 46-47 48-54 55-64 65-80 81-85 86-92 93-97 98-101 102-109 110-119 120-143

PRACTICAL CROP PRODUCTION PROGRAMMEThe idea of introducing a practical training course for under graduate students was started in the year 1974. The existing pattern of Saturday farm practical training, before November, 1974 wherein the final year under graduate students were registering for 2+2 credit hours in trimester, did not provide an integrated and intensive training in raising crops and to go in depth in successful crop production. This was mainly because of the fact that due to the shortage of land, students were not able to continue with plot work throughout the year and also with the start of new trimester a new batch used to come to do the work. Such a practice did not give thorough comprehensive about the field work in raising good crops on scientific lines to achieve the real objectives of higher net yield. The honest efforts of the university towards making every agricultural graduate a real practical farmer came into existence under the able stewardship of the then Vicechancellor, Sh. N.N. Kashyap, ICS who really understood the scope, utility and benefits of the course to the students community with an ultimate objective of developing selfreliance in crop production. The objectives on which the intensive training in the field of crop production started are as follows: (i) (ii) To earn while they learn. To give the students an opportunity to put into practice with their own hands the scientific principles of agricultural production studied by them in several courses of the curriculum. To develop the students capacity to plan the operations for a given holding and work it out with a suitable combination of improved practices to raise maximum crop yield from the land. To train the students under guidance to conduct farming operations as a business, so that economically higher production could be obtained with resultant profit. To learn the division of labour among the team of workers so that best results could be attained with co-operative effort and the art of managing man power is learnt. To develop the faculty of decision making and the execution of agricultural operations in the field. To arouse thinking about the problems faced by farmers and safely lead them to simple experimentation.

(iii)

(iv) (v)

(vi) (vi)

STUDENTS AT WORK ON PRACTICAL CROP PRODUCTION FARM

Mushroom Cultivation

Weeding with longtine hoe

Class in progress

Weeding with longtine hoe

Interculture operation

Herbicide spray

2

Thinning

Bund preparation

Channel preparation

Irrigating the field

Fertilizer application

Fodder harvesting

3

SEED, ITS CLASSES, PROPERTIES, CHARACTERISTICS AND CALCULATIONSeed is the living link between parents and its progeny. Biologically, seed is a ripe, fertilised ovule and a unit of reproduction of flowering plants. Agronomically, a seed, seed material or propagule is the living organ of crop in rudimentary form used for propagation. It can be any part of the crop from which a new crop will grow. Seed is the vital input in crop production because only through seed the investment made on other inputs like pesticide, fertilizer, irrigation and crop maintenance can be realized.The seed required for raising the crop is quite small. Its cost is less as compared to other inputs, but farmer gets greater income depending upon the quality of the small quantity of seed he uses. Therefore, utmost care must be taken to use quality seed. Certified seed guarantees quality and ensures high and assured yield. This emphasises the need for increasing the area under quality seed production. Differences between seed and grain Seed It should be viable one It should have maximum genetic and physical purit. It should satisfy minimum seed certification standards. It should be completely treated with pesticide / fungicide to protect the seed against storage pests and fungi. Respiration rate and other physiological and biological processes should be kept at low level during storage. It Should be compulsorily certified/ truthfully labeled. It Should never be converted into grain unless warranted. It should satisfy all the quality norms. Grain It may not be a viable one It may not have maximum genetic and physical purity. It may not satisfy minimum seed certification standards. It should never be completely treated with any chemical, since it is used for consumption. Respiration rate and other physiological and biological processes may not be kept at low level during storage. No need of certification. It can be converted into seed if the conditions warrant. Quality norms are not considered.

Since seeds are units of propagation of most arable crops, successful crop production relies on establishing an adequate population of vigorous plants for efficient use of natural resources and applied inputs. CHARACTERISTICS OF QUALITY SEED Quality seed ensures uniform crop stand establishment with uniform vigour and population of seedlings per unit area. Selection of good seed is, therefore, of prime importance for remunerative farming. The seed should be of adaptable crop variety or hybrid fitting into the cropping system. Seed should be pure (true to type) with high germination percentage. It should be free from seed borne diseases, insects and insect eggs. They should be large, plump, bold, uniform in size, shape, colour with proper test weight. 4

Seed should be free from noxious, objectionable or satellite weed seeds. The seed should be as fresh as possible or of proper age.

CLASSES OF SEEDS The crop grown for seed production is periodically inspected to determine the level of impurities for maintaining seed standards. After harvest, the seed is subjected to analysis and germination test. The standards for certification of each crop differ, but in all cases they result in the sale of quality seed to the farmers. Four classes of pure seed are recognised by the International Crop Improvement Association. Breeder or nucleus seed: It is directly controlled by the organising or sponsoring plant breeder or institution. It provides for initial or recurring increase of the foundation seed. This is the seed that is produced directly under the supervision of plant breeder. Foundation seed: This includes elite seed, would be seed stock (seeds, tubers, bulbs, plants, etc.) that are so handled as to maintain specific genetic identity and purity and that may be designated or distributed by representatives of an experimental station. Foundation seed is the source of all other certified seed classes, either directly or through registered seed agencies. It is also known as mother seed. The colour of the foundation seed tag is white. Registered seed: This is the progeny of the foundation or registered seed that is so handled as to maintain satisfactory genetic identity and purity and that has been approved and certified by the certifying agency. This class of seed is of a quality suitable for the production of certified seed. It can be produced by the farmers and other growers under special contract with the certifying agency. Registration seed tag is purple. Certified seed: This is the progeny of the foundation, registered or certified seed that is so handled as to maintain satisfactory genetic identity and purity and that is approved certified by the certifying agency. This is the seed designed for use by farmers for crop production. Two classes of certified seed are produced: F1 and F2. Recertification is not permitted from F3 generation of seeds. Certified seed tag contains blue tag. Hybrid seed: is the seed produced by crossing two or more homozygous inbred lines to obtain a desirable type with high yield potential. Only FI generation of hybrids is recommended for use as seed for commercial production. To maintain such FI hybrid seeds, parents are to be maintained and freshly bred each time, particularly, if the same vigour and known desired qualities are to be maintained. Hybrid seed may be the product of single, double or multiple cross. Genetic purity Breeder/Nucleus 100.0% Foundation seed 99.5% Certified seed 99.0% Physical purity: Seed should have the required level of physical purity for certification All crops 98.0% Free from other crop seeds , expressed in number /kg Crop Designated inseparable other crop seeds Barley Wheat, oats and gram Oats Wheat, gram and barley Wheat Oats, gram and barley 5

These are the plants of cultivated crops found in the seed field and whose seed similar to crop seed that is difficult to separate them economically by mechanical means cause physical admixture with the crop seed only when these crop mature approximately at the same time when seed crop matures. Objectionable weed seeds These are plants of weed species which are harmful in one or more of the following ways The size and shape of their seeds are so similar to that of the crop seed that is difficult to remove their seed economically by mechanical means. Their growth habit is detrimental to the growing seed crop due to competing effect Their plant parts are poisonous or injurious to human and animal beings They serve as alternate hosts for crop pests and diseases. Crop Designated Objectionable weeds Berseem Chicory (Chicorum intybus) Cucurbits Wild Cucurbita sp. Kasuri methi Melilous sp. Lettuce Wild lettuce (Lactuca sativa) Bhindi Wild Abelmoschus sp. Rape and Mustard Argemone mexicana Wheat Convolvulus arvensis (Hiran kuri) Paddy Wild paddy (Oryza sativa var. fatua) Free from designated diseases It refers to the diseases specified for the certification of seeds and for which certification standards must be met with. May cause contamination, when they are present in the seed field or with in the specified isolation distance. The objectionable designated diseases and their causal organisms of different crops are as under: Crop Wheat Sorghum Mustard Pearl millet Sesame Brinjal Chilies Cucurbits Cowpea Bhindi Potato Tomato Designated diseases Loose smut Grain smut or Kernel smut Alternaria blight Grain smut Green ear Ergot Leaf spot Little leaf Anthracnose leaf blight Leaf blight Mosaic Anthracnose Yellow vein mosaic Brown rot Root knot nematode Early blight 6 Causal Organism Ustilago tritici Sphacelotheca sorghii Alternaria sp. Tolyposporium penicillariae Sclerospora graminicola Claviceps microcephala Alternaria sp Datura virus Gleosporium piperatum Alternaria solani Cucumis virus Colletotricum sp. Hibiscus virus Pseudomonas solanacearum Meloidogyne incognita Alternaria solan i

Leaf spot

Xanthomonas ves icatoria

Steps to be taken during Seed Production to Insure Genetic Purity Following are the steps which can help in maintaining genetic purity of seed material: 1. Control of seed source Multiplication of seed material from an appropriate class viz. breeders, foundation, registered and certified procured from an appropriate source is essential. 2. Nature of preceding crop In order to maintain genetic purity of the seed there are certain requirements pertaining to the nature of preceding crop which may not deteriorate the seed quality and can help in growing healthy seed crop. Scientific crop rotation should be followed but if the same crop was grown in previous season, under special case, then the fields should be irrigated 3 weeks before sowing to allow germination of shattered seeds of previous crop and they should be destroyed during seed bed preparation like in case of wheat etc. Thus the volunteer plants of same variety or the crop should be destroyed under all the circumstances. 3. Isolation Isolation is an effective distance up to which pollen may be carried by various agencies like insects; wind etc. from commercial crop to the seed crop and results into natural crossing or cross pollination. The seed crop must be grown beyond this distance. 4. Rouging Presence of off type plants causes a potential threat to genetic purity, contamination; however removal of such plants before flowering or before heading may not jeopardize the genetic purity of the seed. The off-types may be produced because of presence of some recessive genes in the variety at the time of release or they may arise by mutation. The off-types may also grow as volunteer if the same crop or variety is grown in pervious year or there had been mechanical mixture due to use of same seed drill, threshing machine, etc. 5. Seed certification To insure the quality pedigree seed it has to be certified by any registered seed certifying agency like HSDC, NSC, TDC, etc. Most qualified and experienced seed certifying personal carry out field inspections to ensure the absence of off-types objectionable weeds and diseased plants in the field of seed crop. These personals also draw seed samples from the seed lots and conduct various seed tests to find out purity, germination, viability and seed healths. The seed lots which meet minimum seed standards are subsequently in its respective seed class. 6. Adoption of an appropriate agronomic practices These practices includes selection of suitable agro-climatic zone in which a successful seed production programme may be carried out, selection of well leveled and fertile plots which are free from water logging, selection of suitable variety, seed type, seed treatment, cultivation practices like using proper seed rate, timely sowing, using proper distance, use of all preventive measures against diseases, insect-pests, weeds, efficient water and nutrient management, timely harvesting, threshing, drying, grading, 7

bagging, etc. These practices help in raising a healthy seed crop for onward distribution to the cultivators for raising a good crop of higher productivity. Higher productivity could also be maintained by renewal of seed lots as under: Seed renewal period in years Crops Wheat Paddy Maize hybrid Sorghum hybrid Sorghum composite Bajra hybrid Barley Gram, pea, lentil, mung, urd Groundnut Cotton varieties Arhar Years 5 4 1 1 2-3 1 5 5 5 5 3

Seed Testing: Farmers often save seed from the current season's crop for planting in the next season. The farmer usually saves seed from plant (s) with desirable features (welldeveloped bold seed free from pests and diseases). In the case of cross pollinated plants, such as maize, farms will have to constantly change the cultivar season after season. Optimum crop stand establishment depends on quality of seed used and soil environment in which it is sown. Seed testing is the procedure for obtaining reliable information about its capacity for establishing adequate crop stand. Most seed testing labs provide information on five aspects of seed quality: viability, purity, vigour, seed health and presence of noxious weed seed. Seed germination: Germination is the transformation of an embryo into a seedling. During the process of germination, the metabolism and growth which were suppress or suspended are resumed. Seedling develops from the seed from its quiescent state. Water is the basic requirement for initiating the chemical reactions. Optimum temperature is essential for good germination. Individual species has its own temperature requirement which occurs within a limited range. Normally the temperature range for germination is 15- 40C. Seed germination is also affected by oxygen supply since it is required for respiration. The primary role of oxygen is electron acceptor in catabolism. Many of the seeds are markedly light sensitive for germination, primarily to the activity of the phytochrome system. Seed viability: Seed viability is defined as the degree to which a seed is metabolically active and capable of germinating under favourable condition. Seed viability is the highest at the time of physiological maturity; Seeds with high moisture content deteriorate quickly due to energy expenditure and accumulation of breakdown process. Ageing is one of the reasons that affect the seed viability of seed increases, the semipermeable membrane of the cell organelles loses their selective permeability and allow 8

the metabolites to leach out. The important changes that take place due to ageing is the degradation of mitochondria which permanently lose their ability of swelling and contraction. Normally the viable seeds of many of the field crops germinate within 3-5 days. It is important to maintain the viability of seeds during germination. Longevity:It means the duration of the viability of seeds. Normally the seeds possess maximum germination potential during the physiological maturity and the deterioration of seed quality occurs from this point of maturation onwards. The rate of deterioration increases due to mechanical injury at the time of harvesting and processing. Higher moisture content in the seed also causes deterioration of seed quality and longevity. Stored seeds exposed to microorganisms and insects cause reduction in longevity. Seeds stored in low moisture, cool temperature and low oxygen tension enable increase in longevity. However, due to aging, there is break down of compounds that are essential for germination and accumulation of toxic by-products. Lipid auto oxidation is one of processes that destroy seed viability due to ageing, particularly in oilseeds. Small millets retain their viability for a long period. The seeds of tobacco remain viable for 10-15 years, if properly stored. Viability testing: Seed viability is the capacity of non-dormant seed to germinate under favourable conditions. There are different techniques for conducting standard germination test including petri dish test and rolled-towel test. Seeds are placed on absorbent material in the dish. Small seeds may be sandwiched between two layers of absorbent material. In the rolled towel test, seeds are arranged in rows and rolled up. Sand and cotton can be used as absorbent material. After placing the seed in appropriate medium, it is placed in a germinator at relative humidity of 90 per cent and a temperature of 20C for 16 hrs, followed by further exposure for 8 hrs at 30C for one to several weeks depending on the seed. Scoring is done by grouping seedlings into different categories as normal, hard seed, dormant seed, abnormal seed and dead or decaying seed. Tetrazolium test is a calorimetric test in which a biochemical reaction causes the test solution to change colour under certain conditions. Tetrazolium (2, 3, 5triphenyltetrazolium chloride) solution is colourless, but changes to red insoluble compound called formagan upon being reduced by hydrogen ion. Viable seed will change colour to red and dead or nonrespiring seeds remain colourless. This test is quick and reliable. Seed purity test: Seed purity is percentage of pure seed (seed without contaminants) in the sample tested. Contaminants include seeds of other crops, weed seed and inert matter. Pure live seed: Pure live seed (PLS) is the per cent of desired cultivar that will germinate. It is a function of both per cent purity and per cent germination. It is calculated as per cent. Per cent = (% germination x % purity) 100 Seed vigour: Vigour of seed is defined as the condition of the seed that permits germination to proceed rapidly and uniformly and allows production of uniform seedling stand. Seed vigour is a pre-requisite for rapid and uniform germination and fast growth of seedlings under field conditions. Vigorous seeds produce seedlings that will have good 9

health and natural robustness. The vigour of the seeds depends on the genome, history of the individual seed and the environment in which it is sown. Seed vigour is normally determined by germination, growth and development, resistance to variations mitochondria and extra active enzyme systems for assimilation, growth and development. Fully mature seeds possess complete physical and physiological development needed for maximum expression of vigour. Prevalence of high humidity and high temperature during seed storage affect the seed vigour and cause loss of viability. Other factors such as mechanical damage attack by pathogens and passage of time also affect the seed vigour. Mechanically affected seeds are prone to infestation by fungi and other microorganism insect incidence, particularly of seed borer (Bruchus), causes damage to the stored seeds which lose their vigour. Vigourous seeds are physically sound, germinate quickly and produce rapidly developing seedlings. Seed vigour test: Seed vigour indicates the properties of seed that determine its potential for rapid, uniform emergence and development of normal seedlings under a wide range of field conditions. It is influenced by genetic factors and external environmental conditions during seed development and maturity, harvest and storage. An environment of high temperature and humidity adversely affects seed vigor. In cold test, seed samples are placed on an appropriate medium in a cold environment at l0oC for 7 days and brought to an environment mediated at 25C for 4 days. The seeds that emerge are counted. In accelerated aging test, imbibed seeds are kept at high temperature (45C) and at high relative humidity (100%) for about 4 days. The seeds are then placed under optimal conditions for germination. Vigorous seeds survive this harsh treatment. Seed health: It evaluates the presence of pathogens and insect pests on the seed. Seed heath may be evaluated visually (change in testa colour, presence of spores etc) after incubating on an appropriate medium for disease development. It can also be determined by biochemical test such as enzyme linked immunosorbent assay (ELISA). Mechanical seed damage: Mechanical damage to seed affects seed quality. Damage may include readily visible splits or cracks in testa or chips of cotyledons. Physically damaged seeds are prone to rotting when planted in the soil. Mechanical damage to seed may be evaluated by soaking a sample in 0.1 per cent household bleach (sodium hypochlorite) for 15 minutes. Seeds with cracks in testa will imbibe the solution and the testa will separate from cotyledon. Test weight: refers to either weight of a fixed number of seeds, e.g., 100 seed weight or 1000 seed weight or seed weight from a fixed volume, e.g., seeds filled in test tube. Calculation of real value (RV) of seed Real value of seed is calculated as follows: RV = Purity (%) x Germination (%) 100 Calculation of seed purity Pure live seed (PLS) is calculated as follows: PLS= Purity (%) x Viability (%) 100 10

The test weight of some important crops is given as underCrop Cereals Wheat Barley Oats Maize Rice Sorghum Pearlmillet Ragi Pulses Chickpea Desi Chickpea Kabuli Lentil Pigeonpea Mung Urd Moth Cowpea Soybean Fieldpea Rajmash Oilseeds Linseed Rapeseed Groundnut Sesamum Sunflower Saflower Castor Fibre crops Cotton Hybrid Cotton Bt Sunnhemp Green Manuring Crops Sesbania Sunnhemp Clusterbean Medicinal crops Isabgol Methi Forage crops Lucerne Berseem Alkloid crops 140 300 40 60 30 30 25 32 100 30 250 10 4.5 350-500 6 44 35 500 145 145 15 20 15 30 2 20 2.4 2.5 7140 3330 25000 16670 33340 33340 40000 31250 10000 33340 4000 100000 222220 2860-2000 166670 22730 28570 2000 7000 7000 66660 50000 66660 33340 500000 50000 416670 400000 45 37 32 220 25 15 7 8 22220 27020 31250 4540 40000 66660 142850 125000 1000 seed weight.(g) Seeds per kg. ('000)

11

Tobacco 2 500000 Calculation of seed rate: Example 1: Calculate the seed rate of wheat for one hectare area with following observation: Spacing = 20X 5cm, Test weight of seed = 40 g, Establishment of plants = 70%, Purity percentage = 90, Germination percentage = 90. Solution: Purity % X Germination % Real value of seed = ----------------------------------100 x100 90 X 90 Real value of seed = ---------------- =0.81 100 x100 Area in one hectare Plant population needed/ha = ------------------------------------Space occupied by each plant

100 X 100 X100 X 100 Plant population needed/ha = ----------------------------- = 1000000 plants 20 X5 Plant population needed X Weight of one seed Seed rate /ha = ---------------------------------------------------------------------------Unit established plants X Real value of seed X1000X100 1000000 X 40 X 100 X100 Seed rate needed/ha = ----------------------------------- = 70.546 kg/ha 70 X 1000 X 81X1000 X100 Example 2: Calculate the seed rate of hybrid cotton for one acre area with following observation: Spacing = 67.5 X 30 cm,Test weight of fuzzed seedand unfuzzed seed is 140 and 150 g, respectively, Purity percentage = 90. Germination percentage = 80. Solution: Purity % X Germination % Real value of seed = ----------------------------------100 x100 90 X 80 Real value of seed = ---------------- =0.72 100 x100 Area in one acre Plant population needed/ha = ------------------------------------Space occupied by each plant 4000 X100 X100 Plant population needed/ha = ----------------------------- = 19753 plants 67.5 X30 Plant population needed X Weight of one seed 12

Seed rate Kg/ac. = ------------------------------------------------------------------Real value of seed X1000X100 19753 X 1.4 X 100 Seed rate (fuzzed seed) needed/ac = ----------------------------- = 3.84 kg/ac. 72 X 81X1000 X100 19753 X 1.5 X 100 Seed rate (unfuzzed seed) needed/ac = ----------------------------- = 4.115 kg/ac. 72 X 81X1000 X100 Example 3: Determine the seed requirement of rice to be transplanted in 5 acre with the following information: Seed germination = 90%, Seed purity = 90%, Test weight = 25 g, Spacing between hills = 15 cm x 15 cm, Number of seedlings per hill = 2, Damaged seedlings during uprooting = 10%, Seedling required for gap filling = 10%. Solution: 90 x 90 Real value of seed = ---------------- = 0.81 100 x 100 5 x 4000 x 100 x 100 x 2 Plant population required for 5 acre = ------------------------------ = 1777778 plants 15 x 15 110 No. of seedlings required to replace damaged seedlings during uprooting = ------100 110 No. of seedlings required to replace damaged seedlings during uprooting = ------100 1777778 x 110 x 110 Plant population needed in nursery = ---------------------------- = 2151111 plants 100 x 100 2151111 x 100 x 25 x 1000 Seed rate required for 5 acre = --------------------------------- = 66.39 kg 81 x 1000 Example 4: Work out the seed rate of sugarcane to be planted with 3 buded setts for one hectare from the given data: No. of buds on a cane = 30, No. of damaged buds on a cane = 5, Row spacing = 60 cm, Length of each sett = 30 cm, Average weight of a cane = 1 kg. 13

10000 x 100 x 100 Solution: No. of setts needed per hectare = ---------------------------- = 55555 setts 60 x 30 No. of buds/ sett x No. of setts /ha No. of canes needed /ha = --------------------------------------------------------------No. of buds per cane No. of damaged bud per cane 3 x 55555 No. of canes needed /ha = -------------------= 6666.6 canes 30 5 Weight of 6666.6 canes = 6666.6 x 1 = 6666.6 kg = 66.666 q/ha Example 5: Find out the seed requirement of berseem for 2 kanal area sowing through broadcasting method with required plant stand of 400 plants / m2. The test weight of berseem is 2.0 g, purity 90%, germination 90% and seedling establishment 80%. Solution: 90 x 90 Real value of seed = ---------------- = 0.81 100 x 100 Plant stand required = 1000 x 400 = 400,000 plants 400,000 x 2 x 100 x 100x 1 Seed rate required = ------------------------------------- = 1.234 kg 100 x 81 x 80 x 1000

14

SOIL FERTILITY AND PLANT NUTRITIONThe term soil fertility refers to the inherent capacity of soil to supply mineral nutrients. Soil productivity is related to the ability of a soil to produce yield economic products. It is the broader term since fertility is only one of a number of factors that determine the magnitude of crop yields. Difference between soil fertility and soil productivity Soil fertility (i) It is considered as an index of nutrients availability to plants. (ii) It is one of the factors for crop production. The other factors are water supply, slope of the land, depth of water table etc. (iii) It can be analysed in the laboratory. (iv) It is potential status of the soil to produce crops. Soil productivity (i) It is a broader term used to indicate yields of crops. (ii) It is the interaction of all the factors that determine the magnitude of yields. (iii) It can be assessed in the field under particular climatic conditions. (iv) It is the resultant of various factors influencing crop yield.

The Arnon's criteria of essentiality of elements in plant nutrition (i) A deficiency of the elements makes it impossible for the plant to complete its life cycle. (ii) The deficiency symptom of the element in question can be prevented or corrected only by supplying the elements. (iii) The element is directly involved in the nutrition of the plant and can not be replaced with other apart from its possible effect in correcting some microbiological or chemical condition in the soil. List of the essential nutrients required for plant growth Seventeen elements have been considered essential for plant growth are: _______________________________________________________________________ _ Mostly from air and water From soil solids ----------------------------------------------------------------------------------------------------Macronutrients Micronutrients -------------------------------------------------------------------------------------------------Carbon(C) Nitrogen (N) Iron (Fe) Copper (Cu) Hydrogen (H) Phosphorus(P) Manganese (Mn) Zinc (Zn) Oxygen (O Potassium (K) Boron (B). Chloride (CI) Calcium (Ca) Molybdenum (Mo) Cobalt (Co) Magnesium (Mg) Sulphur (S) _____________________________________________________________________ Classification of the essential elements based on the physiological functions Considering the role played by various essential elements they may be grouped as follows:Group Role Essential elements

15

I II III IV

Energy exchanges Energy stores Translocation regulators Oxidation-reduction regulators

Hydrogen, oxygen Carbon, nitrogen, phosphorous& sulphur Potassium, sodium, calcium and magnesium Manganese, molybdenum, iron, copper, boron, cobalt & zinc

Difference between macro and micronutrients Elements which are required by plants in concentrations exceeding one part per million, often ten times that or more are called macronutrients. Elements which are required by plants in concentrations less than 1 ppm are considered as micronutrients. The forms of different nutrients elements used by plants Nutrients absorbed in uncombined form Nutrient Potassium Calcium Magnesium Iron Mangenese Copper Zinc Chlorine Nutrients absorbed in combined form or as salts Nutrient Nitrogen Phosphorus Sulphur Boron Molybdenum Carbon Hydrogen Form NH4+(ammonium), NO3 --(nitrate) PO4--(phosphate) HPO4- (phosphate)*H2PO4(orthophosphoric acid) SO3(sulphite), *SO"4 (sulphate) *BO3- -(borate) , HB4O7 (biborate) HMoO4- (molybdate) CO3 - -(Carbonate), H+ , *HCO3 (bicarbonate) HOForm K+ Ca++ Mg++ Fe++ (Ferrous), Fe+++ (Ferric) Mn++ (Manganous), Mn+++(Manganic) Cu+ (Cuprous), Cu++ (Cupric) Zn++ CI-

* Indicate the forms in which most plants take up these nutrients. Functions of essential nutrients Carbon Basic molecular component of carbohydrates, proteins, lipids and nucleic acids. Oxygen It is somewhat like carbon in that it occurs in virtually all organic compounds of living organisms. Hydrogen Plays a central role in plant metabolism. Important in ionic balance and as main reducing agent and plays a key role in energy relations of cells. Nitrogen It is a component of many important organic compounds ranging from protein to nucleic acids. It is an integral part of chlorophyll, which is the 16

primary absorber of light energy needed for photosynthesis. It imparts green colour to plants. Phosphorus Central role in energy transfer and protein metabolism. It is an important structural component of many biochemicals inluding nucleic acids. DNA and RNA are associated with control of hereditary processes. It is also associated with increased root growth and early maturity of crops. Potassium Helps in osmotic and ionic regulation. It functions as cofactor or activator for many enzymes of carbohydrate and protein metabolism. Imparts disease resistance in cereals and drought resistance in many crops. Calcium It is involved in cell division and plays a major role in maintenance of membrane integrity. Magnesium Component of chlorophyll and a cofactor for many enzymatic reactions. It is a structural component in ribosomes. Sulphur Like phosphorus, it is involved in plant cell energetics. It is associated with chlorophyll formation and sulphur containing amino acids. Iron An essential component of many hemo and non-hemo Fe enzymes and carriers, including cytochromes (respiratory electron carriers) and the ferredoxins. The latter are involved in key metabolic functions such as N fixation, photosynthesis and electron transfer. Zinc It is a constituent of several enzyme systems regulating various metabolic reactions. Manganese Involved in oxygen evolving system of photosynthesis. It can substitute for magnesium in many of the phosphorylating and group transfer reactions. It influences auxin levels in plants. CopperIt acts as electron carrier in enzymes associated with oxidation-reduction reactions. It has indirect effect on nodule formation. Boron It is essential for development and growth of new cells in plant meristcm. It is necessary for nodule formation in legumes. It is associated with translocation of sugars, starches, nitrogen and phosphorus. Molybdenum It is an essential component of enzyme nitrate reductase in plants. It is also a structural component of nitrogenase associated with nitrogen fixation in legumes. Chlorine Essential for photosynthesis and as an activator of enzymes involved in splitting water. Associated with osmoregulation of plants growing on saline soils. Nikle It influences urease activity in nitrogen metabolism and facilitates transport of nutrients to seed or grain. In free living Rhizobia, its supply is necessary for hydrogenase activity. VISUAL SYMPTOMS The cheapest diagnostic technique for identifying nutrient disorders in crop plants is visual symptoms. However, visual symptoms are some times confused with disease, insect or soil moisture stress. There are three steps in identifying nutrient disorders by visual symptoms.

17

(l)

Observing plant for its normal growth and development: stunted growth may be due to deficiency or toxicity of all elements, but N and P deficiencies have more influence on growth reduction, (2) Plant part affected: whether foliar symptoms appear on lower or older leaves, or on younger or growing points of the plant, and (3) Recognition of nature of symptoms: chlorotic, necrotic or deformed. If symptoms appear on lower leaves, they may be due to deficiency of mobile nutrients such as N, P, K and Mg. Mobile nutrients are those which can be translocated within plants. Hence, deficiency symptoms occur first on the lower part of the plant. If deficiency symptoms first appear on the upper young leaves, they may be due to deficiency of immobile nutrients such as Ca, Fe, Cu, S, B, Mn and Mo. Immobile nutrients are not translocated to the growing region of the plant but remain in older leaves where they were originally deposited after absorption from the soil. Key points in identification of nutrient deficiency symptoms in crops are given in following table. Practical applicability of this method is rather limited. Symptoms are often vitiated by the interaction of elements and also by the intensification of pests and diseases. The very fact that crop is showing deficiency symptoms indicates that its growth and development has already been hindered and optimum yield may not be possible even after the remedy. Deficiency symptoms may vary from species to species and even from variety to variety. Plants may not exhibit deficiency symptoms due to hidden hunger. GENERAL DESCRIPTION OF NUTRIENT DEFICIENCY SYMBTOMS Nutrient ________________________________Symptoms_______________________ N Stunted growth, chlorosis (yellowing) first on lower leaves, reduced tillering in cereals. P Purple orange colour of older leaves, new leaves dark green, poor root system, stunted growth. K Older leaves may show spots or marginal burning starting from tip. Ca Failure of terminal bud and root tips, growing point die and curl, new leaves become white. Mg Interveinal chlorosis of older leaves with veins remaining green, pinkish colour of old leaves. S Chlorosis of younger leaves, severe deficiency leads to chlorosis of entire plant. Zn Characteristic little leaf and rosetting or clustering of leaves at the top of fruit trees. In sorghum, its deficiency is called white bud, cotton little leaf and in citrus mottle leaf. Fe Interveinal chlorosis of younger leaves, severe deficiency leads to yellowing of entire leaf first and finally white. Mn Similar to iron deficiency, at advanced stages, necrosis develops instead of white colour. Cu Chlorosis of young leaves, rolling and dieback. In advanced stages dead tissue appears along the tips and edges of leaves similar to that of potassium deficiency. Mo Mottled pale appearance in young leaves, bleaching and withering of leaves. 18

B

Thickened or curled leaves, thickened, cracked or water-soaked condition of petioles and stem, cracking or rotting of fuuits, tubers or roots

19

NUTRIENT DEFICIENCY SYMPTOMS

N-deficiency (Wheat)

N-Deficiency (Soybean)

N-Deficiency (Tobacco)

N-Deficiency (Maize)

Zn-Deficiency (Rice)

Fe-Deficiency (Groundnut)

P-Deficiency (Sugarcane)

Fe Deficiency (Maize)

Mn-Deficiency (Wheat)

N-Deficiency (Rice)

P-Deficiency (Maize)

Fe-Deficiency (Rice)

20

Fe-Deficiency (Groundnut)

P-Deficiency (Brassica napus)

Mn-Deficiency (Wheat)

Mn-Deficiency (Berseem)

N-Deficiency (Soybean)

P-Deficiency (Wheat)

P-Deficiency (Sorghum)

P-Deficiency (Sugarcane)

N-Deficiency (Wheat)

K-Deficiency

S-Deficiency (Wheat)

K-Deficiency (Berseem)

21

Nutrient Response on Yield

Nutrient Deficiency Symptoms

22

Deficiency diseases caused by micronutrient deficiency are as follows: Iron= Bright yellow green or yellow chlorosis in grain crops. Manganese= Grey speck of oats, Speckled yellows of sugarbeet. Marsh spot of peas. Pahala blight of sugarcane. Copper= White tip in grain crops. Zinc= White bud of maize. Khaira disease of rice. Molybdenum= Yellow spot of citrus. Boron= Crown rot or dry rot of sugarbeet. Top sickness of tobacco. Fertilizers are the nutrient supplying chemicals in concentrated form. There are different form/types of fertilizers supplying essential nutrients. Some fertilizers supply only one nutrient and are called straight fertilizers, where as, there are some fertilizers which supply more than one nutrient are called complex fertilizers. Classification of nitrogen fertilizers 1. Nitrate (NO3) fertilizers N content (%) Sodium nitrate Na NO3 15-16 Calcium nitrate Ca(NO3)2 33-35 Potasium nitrate KNO3 13.00 2. Ammonium (NH4) fertilizers Ammonium sulphate (NH4)2 SO4 20.60 Ammonium phosphate NH4H2PO4 20.00 Ammonium chloride NH4Cl 25.00 Anlydrous ammonia NH3 81.50 3. Nitrate & ammonium fertilizers Ammoium nitrate NH4NO3 33.50 Calcium ammonium nitrate CaNH4 NO3(NH4NO3.CaCO3) 25.00 Ammonium sulphate nitrate (NH4)2 SO4.NH4NO3 26.00 4. Amide (CN2) fertilizers Urea CO (NH2)2 46.00 Calcium cyanamide CaCN2 21.00 Relative efficiency of nitrogen fertilizers: Based on the experiment results the following conclusions have emerged: Under most conditions urea, calcium ammonium nitrate and ammonium sulphate, on equal nitrogen basis, are equally effective. Ammonical fertilizers are more effective than nitrate fertilizers fro lowland rice. Nitrate nitrogenous fertilizers are better suited for top dressing. For crops such as tea, ammonium sulphate is more effective than others.

23

Phosphatic fertilizers Fertilizers Single super phosphate Triple super phosphate Dicalcium phosphate Calcium metaphosphate Rock phosphate Basic slag Mono-ammonium phosphate Diammonium phosphate Ammonium phosphate sulphate Nitrophosphate (ODDA) Nitrophosphate (PEC) Potassium metaphosphate

Total (%) P2O5 N (%) 16.0 48.0 34.0 63.0 27.0 2.5-7.5 48.0 11.0 46.0 18.0 20.0 16.0 20.0 20.0 14.0 16.0 60.1 -

Relative efficiency of phosphatic fertilizers For short duration crops and those with restricted root system, fertilizers with high proportion of water soluble phosphorus are advantageous. Higher water soluble phosphorus is less important for long duration crops. Higher water solubility is desirable for crops requiring quick start. Localized placement of water soluble phosphate fertilizers is more effective when the rate of application is limited. On acid soils, granular fertilizers with high degree of water solubility are most effective than powdered fertilizers to be mixed with soil. On acid to neutral soils, band placement of powdered fertilizers with high degree of water solubility will give better results than mixing the fertilizers with soil. On calcareous soils, granular water soluble phosphate is more effective. Fertilizers with low solubility will give good results when applied in powdered from mixed with soil. Monoammonium phosphate is better than diammonium phosphate on calcareous soils. Rock phosphate and bone meal are ideal for strongly acid soils and for long duration crops. Potassium fertilizers Murate of potash Potassium sulphate Potassium nitrate KCl K2SO4 KNO3 24 K2O(%) 60 48 44

Sulphate containing fertilizers and soil amendmentsFertilizer/amendments Sulphur (%) Fertilizer/amendment Sulphur (%)

Ammonium sulphate Ammonium phosphate Ammonium phosphate sulphate Basic slag Single super phosphate Micronutrient carriers Micronutrient Zn

23.7 4.5 15.4 12.4 22.4

Potassium sulphate Gypsum Copper sulphate Ferrous sulphate Zinc sulphate

17.8 23.5 12.8 18.8 17.8

Name of salt

Zinc sulphate heptahydrate Zinc sulphate monohydrate Zinc oxide Zinc EDTA Copper sulphate pentahydrate Copper sulphate monohydrate Copper EDTA Manganese sulphate trihydrate Manganese sulphate monohydrate Manganese Ferrous sulphate Iron EDTA Borax Boric acid Solubor Sodium molybdate Ammonium molybdate Potassium chloride

Micronutrient content (%) 21 33 55-70 12 24 35 9-13 26-28 30-32 5-12 19 12 10.5 17.5 19 37-39 52 48

Cu Mn Fe B Mo Cl

Antagonism among different essential plant nutrients Some of the enzymatic and biochemical reactions requiring a given micronutrient may be poisoned by the presence of other second trace element in toxic quantities: (i) Molybdenum use is limited by excess copper or sulphur (ii) Excess Zn, Cu or Mo encourages iron deficiency (iii) Excess phosphorous deficiency of Zn, iron or copper but increases Mo uptake (iv) High level of nitrogen intensify Cu and Zn deficiencies (v) Excess Na and K may affect Mn uptake (vi) Boron uptake is limited by excess lime (vii) Excess Fe, Cu or Zn may reduce Mn absorption 25

Organic manures: Organic manures are the decomposed organic matter. These are having plant nutrients in low concentration and are required in large quatity, hence, called bulky manures. These are crop residue or animal excreta.AVERAGE NUTRIENT CONTENT OF ORGANIC MANURES Manure N (%) P2O5 (%) Bulky organic manures Farm yard manure 0.5-1.5 0.4-0.8 Compost (urban) 1.0-2.0 1.0 Compost (rural) 0.4-0.8 0.3-0.6 Green manures (averages) 0.5-0.7 0.1-0.2 Non edible cakes Castor cake 5.5-5.8 1.8-1.9 Mahua cake 2.5-2.6 0.1-0.9 Karanj cake 3.9-4.0 0.9-1.0 Neem cake 5.2-5.3 1.0-1.1 Safflower cake 4.8-4.9 1.4-1.5 (undecorticated) Edible cakes Coconut 3.0-3.2 1.8--1.9 Cotton seed cak\) 6.4-6.5 2.8-2.9 (decorticated) Cotton seed cake 3.9-4.0 1.8-1.9 (undecorticated) Groundnut cake 7.0-7.2 1.5-1.6 Linseed 5.5-5.6 1.4-1.5 Niger 4.7-4.8 1.8-1.9 Rapeseed 5.1-5.2 1.8-1.9 Sesame or til, cake 6.2-6.3 2.0-2.1 Manure of animal origin Dried blood 10.0-12.0 1.0-1.5 Fish manure 4.0-10.0 3.0-9.0 Bird guano 7.0-8.0 11.0-14.0 Bone meal (raw) 3.0-4.0 20.0-25.0 Bone meal (steamed) 1.0-2.0 25.0-30.0 Activated sludge (dry) 5.0-6.5 3.0-3.5 Settled sludge (dry) 2.0-2.5 1.0-1.2 Night soil 1.2-1.3 0.8-1.0 Human urine 1.0-1.2 0.1-0.2 Cattle dung + urine 0.60 0.15 Horse dung + urine 0.70 0.25 Sheep dung + urine 0.95 0.35

K2O (%) 0.5-1.9 1.5 0.7-1.0 0.6-0.8 1.0-1.1 1.8-1.9 1.3-1.4 1.4-1.5 1.2-1.3 1.7-1.8 2.1-2.2 1.6-1.7 1.3-1.4 1.2-1.3 1.3-1.4 1.2-1.3 1.2-1.3 0.6-0.8 0.3-1.5 2.0-3.0 0.5-0.7 0.4-0.5 0.4-0.5 0.2-0.3 0.45 0.55 1.00

Green manure crops and the quantity of nutrient added These are protein rich crops which are rich in nitrogen and succulent in growth. High succulancy helps in easy and early decomposition after turning in soil by ploughing at flowering stage with maximum biomass addition and early decomposition because of low fibre content. 26

N content and addition by leguminous green manuring crops Crop Av. Yield of Green N content (%) N added (Kg/ha) matter (q/ha) green Sannhemp 212 0.43 75.0 Sesbania 200 0.42 68.9 (Dhaincha) Mung 80 0.53 34.5 Cowpea 150 0.49 50.3 Cluster bean 200 0.34 55.7 (Guar) Senji 286 0.51 120.0 Khesari 123 0.54 54.9 Berseem 155 0.43 54.2 Chemical composition of the straw fed to animals Crop straw Percent content N P2O5 Paddy 0.36 0.08 Wheat 0.53 0.10 Sorghum 0.40 0.23 Pearlmillet 0.65 0.75 Maize 0.42 1.57 Biofertilizers and their probable fixing capacityA. 1. 2. 3. Association Nitrogen Symbiotic Associative Free living Strains Rhizobia, Frambia, Anabeena Azospirillum, Acetobactor, Herbspirillum a) Azotobacter, Derxia, Cyanobacteria, Rhodospirillum, Beijerinckia b) Blue green algae (Tolypothrix, Nestoc, Calottria, Plectonema) Pseudomonas and Bacillus VAM (Vesicular Arbicular Mycorrhiza) Remarks 40 750 kg N/ha 20 40 kg N/ha 20 40 kg N/ha 12 15 kg N/ha

K2O 0.71 1.10 2.17 2.50 1.65

B.

Phosphorus Phosphorus solublizers

Can provide 30 kg P2O5/ha Reduce the requirement of phosphorus by 20%

Rhizobium bacteria species responsible for nitrogen fixation in different legumes Group Rhizobium species Legume Alfalfa R. meliloti Melilotus (certain clovers), Medicago (alfalfa), Trigonella Clover R.trifolii Trifolium spp. (clovers) Soybean R.japonicum Glycine max (soybeans) Lupini R. lupine Lupinus (lupines), Ornithopus spp. (serradella) Bean R. phaseoli Phaseolus vulgaris (dry bean), Phaseolus coccineus Peas R. leguminosarum Pisum (peas), 27

Crop groups based on response to salt stress Sensitive group Resistant group Highly sensitive Medium sensitive Medium tolerant Highly tolerant Lentil Radish Spinach Barley Mash Cowpea Sugarcane Rice (transplanted) Chickpea Broadbean Raya Cotton Beans Vetch Rice (direct sowing) Sugarbeet Peas Millets Wheat Tabacco Maize Pearl millet Safflower Clover, berseem Oats Taramira Alfalfa

Calculation on fertilizer requirementExample 1 : For one hectare cultivation of wheat calculate the amount of calcium ammonium nitrate, single super phosphate and murate of potash fertilizers if one one to apply 150 kg N, 60 kg P2O5 and 60 kg K2O per hectare nutrients. Solution: Wheat area to be cultivate = 1 ha or 10,000 m2 amount of nutrients needed to be applied: N = 150 kg, P2O5 = 60 kg and K2O = 60 kg. Fertilizers available: Calcium ammonium nitrate (CAN) = 25% N Single ammonium phosphate (SSP) = 16% P2O5 Murate of potash (MOP) = 60% K2O Since we are aware total amount of nitrogen to be applied to the crop is 150 kg and among the above three fertilizers CAN contains only 25% N and other two fertilizers do not have N content so all the amount of nitrogen should be met through CAN. 150 X 100 Amount of CAN required = --------------- = 600 kg 25 Similarly, single super phosphate contains only 16% P2O5 60 X 100 Therefore, the total amount of SSP = ------------= 375 kg 16 60 X 100 Similarly, the amount of MOP required = ------------= 100 kg 60 Therefore, 600 kg CAN, 375 kg SSP and 100 kg MOP is required to provide 150 kg N, 60 kg P2O5 and 60 kg K2O per hectare to the wheat crop. Example 2: Calculate the quantity of urea, DAP and murate of potash for a crop to be grown in 2 acre area. The crop requires 120 kg N, 60 kg P 2O5 and 40 kg K2O per hectare. Solution : Total are under the crop = 2 acre or 8000 m2 2 Nutrient required in 1 ha (10000 m ) area are: Nitrogen P2O5 K2O = = = 120 kg 60 kg 40 kg 28

But we have to apply fertilizer to 8000 m2 is as follows:120 X 8000 Nitrogen = ---------------- = 96 kg 10000 60 X 8000 P2O5 = ---------------- = 48 kg 10000 40 X 8000 K2O = ---------------- = 32 kg 10000 Fertilizers available: Urea = 46% N, DAP = 18% N and 46% P2O5 and murate of potash = 60% K2O Now we can calculate the individual fertilizers. But here one point must be noted that available fertilizers Urea and murate of potash contains only single nutrient but DAP contains two nutrient elements i.e. nitrogen and phosphorus. Therefore, first it is required to find out the amount of DAP to meet 48 kg P2O5 per 8000 m2 demand. 48 X 100 Quantity of DAP required for 48 kg P2O5 = ------------- = 104.35 kg 46 18 X 104.35 Nitrogen in 104.35 kg DAP = ----------------- = 18.78 kg N 100 Total nitrogen required = 96 kg Nitrogen supplied through DAP = 18.78 kg Balance N to be supplied = 96 18.78 = 77.22 kg Now, 77.22 kg N should be supplied through Urea (46%) 100 X 77.22 Therefore, the quantity of Urea required = ---------------- = 167.87 kg 46 100 X 32 Similarly, the quantity of murate of potash = ------------- = 53.33 kg 60 Hence, to meet the crop requirement 167.87 kg Urea, 104.35 kg DAP and 53.33 kg murate of potash is required. Example 3: Estimate total quantity of fertilizers for a crop to be grown in 4000 m2 area. The crop requires 150 kg N, 50 kg P and 40 kg K per hectare. The fertilizers available with the farmer are Urea, SSP and MOP. Solution: Area to be grown = 4000 m2 2 Nutrient required in 1 ha (10000 m ) area are: 150 kg N, 50 kg P and 40 kg K. 2 So, the nutrient required for 4000 m is as follows:150 X 4000 N = ---------------- = 60 kg 10000 50 X 4000 P = ---------------- = 20 kg 10000

29

40 X 4000 K = ---------------- = 16 kg 10000 Convert P into P2O5 and K into K2O because SSP and MOP fertilizers contains 16% P2O5 and 60% K2O. P2O5 = P X 2.29 = 20 X 2.29 = 45.8 kg K2O = K X 1.20 = 16 X 1.20 = 19.2 kg Now, we are aware that for 4000 m2 area the nutrient required as per recommendation is:N = 60 kg P2O5 = 45.8 kg K2O = 19.2 kg Now, calculate the quantity of individual fertilizer:100 X 60 Quantity of Urea required = ------------= 130.43 kg 46 100 X 45.8 Quantity of SSP required = --------------- = 286.25 kg 16 100 X 19.2 Quantity of MOP required = --------------- = 32 kg 60 Example 4 : Calculate the quantities of urea, SSP and MOP for sugarcane crop to be grown on half acre area. The crop requires 250 kg N, 100 kg P2O5 and 60 kg K2O per hectare. Vermicompost (N 2%, P2O5 1% and K2O 1%) @ 10 t per hectare was applied at the time of field preparation. Solution : Total area under wheat crop = Half acre or 2000 m2 Vermicompost application = 10 t/ha or 10000 kg /10000 m2 or 1 kg/m2 = 1 X 2000 = 2000 kg

Amount of vermicompost applied in wheat crop Nutrient content in vermicompost =

N 2%, P2O5 1% and K2O 1% (as given) 2 X 2000 Amount of N supplied through vermicompost = ------------= 40 kg 100 1 X 2000 Amount of P2O5 supplied through vermicompost = ------------= 20 kg 100 1 X 2000 Amount of K2O supplied through vermicompost = ------------= 20 kg 100 Rate of nutrient application per hectare = 250 kg N, 100 kg P2O5, 60 kg K2O per hectare. But we have half acre area or 2000 m2. 250 X 2000 Therefore, for 2000 m2 N required is = ---------------- = 50 kg 10000 30

Therefore, for 2000 m

2

P2O5 required

= =

Therefore, for 2000 m2 are K2O required

100 X 2000 ---------------- = 10000 60 X 2000 ---------------- = 10000

20 kg 12 kg

Balance amount of N required:Total N N supplied through vermicompost = 50 40 = 10 kg Similarly, P2O5 required = 20 20 = 0 (Nil) Similarly, K2O required = 12 20 = -8 (Nil) 100 X 10 Quantity of Urea required = ------------= 21.7 kg 46 No, SSP and MOP is required as the full dose of P2O5 and K2O was supplied through vermicompost. Example 5: On a field of one hectare wheat is to be sown after mungbean. Calculate the amount of Urea and SSP required if the dose of N and P2O5 are 120 and 60 kg per hectare. Assume that mungbean left the residual nitrogen in the field @ 20 kg per hectare. As per soil test report the field was found sufficient in potash. Solution : Amount of N required = 120 kg per hectare Amount of P2O5 required = 60 kg per hectare Residual N of mungbean = 20 kg per hectare Balance N required for wheat crop = 120 20 = 100 kg 100 X 100 --------------- = 217.39 kg 46 100 X 60 Therefore, quantity of SSP required = --------------- = 375 kg 16 Example 6: Calculate the quantity of water required to spray 0.5% zinc sulphate along with 3% urea at anthesis stage to remove the zinc deficiency in one acre area. If the knapsack sprayer of 15 litre capacity saturates the crop canopy in 250 m 2 area. Solution : 250 m2 area is sprayed with = 15 litre water 1 , , , , , , , , , , , , , , , , , , = 15/250 , , , , 4000 m2 , , , , , , , , , , , , , = 15/250x 4000 = 240 litre. Example 7: How much amount of urea is needed to make 3% urea solution for spray of wheat crop in one acre area at anthesis. Solution : In 100 litre water the quantity of urea required = 3 kg 1, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , = 3/100 kg 240 , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , = 3/100 x 240 = 7.2 kg Example 8: How much amount of zinc sulphate is needed to spray 0.5% solution in wheat crop in one acre area at anthesis? Solution : In 100 litre water the quantity of zinc sulphate required = 500 g 1, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , = 500/100 240 , , , , , , , , , , , , , , , , , , , , , , = 500/100 x 240 = 120 g=1.2 kg Therefore, quantity of Urea required = 31

PRACTICES TO INCREASE THE EFFICIENCY OF APPLIED FERTILIZERS1. The fertilizer scheduling must be based on soil tests. 2. Selection of fertilizers should be done according to the soil reaction viz. acidic fertilizers for alkaline soils and alkaline fertilizers for acidic soil reactions. 3. Surface application through broadcasting should not be adopted but the fertilizer should be placed about 3-4 cm by the side or, below the seed. 4. Optimum and balanced use of fertiliser: Neither too low nor any alone nutrient can increase the productivity therefore, it is essential that most optimum dose of fertiliser and balanced quantity of nutrients should be applied. 5. About 30 to 50 kg N ha-1 should be reduced after raising a legume crop, growing Azolla, blue green, algae or practicing green manuring. 6. The phosphatic and potassic fertilizers should be basal placed because P2O5 and K2O are not lost from the soil but they are adsorbed by the soil particles. Their poor mobility restrict them to the place of application, therefore, they must be placed in the root zone. 7. Split application of phosphate fertiliser in soils prone to phosphate fixation (in acidic soils) or reversion (in sodic soils) gives better response. 8. Home mixing of fertilizers should be in accordance with fertilizer mixing guide and such fertilizer mixtures must be applied as soon as possible. 9. In case of heavy soil types half of nitrogenous fertilizers should be basal placed and rest half should be top dressed in one split only but in case of light soils. N should be applied in three equal splits i.e. 1/3 as basal, 1/3 after 30 days of sowing and rest 1/3 about 50-60 days after sowing. 10. Flooding with too deep water or poor drainage should be avoided after application of fertilizers at least for a week time. 11. Top dressing should be done after draining out the water and weeding so that the loss of nutrients is minimum. 12. The paddy fields used for transplanting should be puddled and fertilizers should be applied at the time of puddling because this will help the fertilizers to reach and get stored in reduced zone of the soil. 13. Skipping the basal application of nitrogen in transplanted/deep water rice and its application after 3-4 weeks of transplanting increases recovery. 14. Light sandy, calcarious and soils under very high cropping intensity are deficient in micronutrients like zinc and sulphur. The deficient plants become sickly and cannot absorb nutrients, thus the fertilizer is not absorbed, therefore such soils must be supplied with zinc sulphate (ZnS04) at the rate of 20-25 kg/ha every after 2-3 years. 15. The acidic soils should be treated with liming materials as and when required. 16. Drilling of fertilisers under irrigated conditions and deep placement under dryland conditions increases fertiliser use efficiency and boosts productivity. 17. Deep placement of fertilizers along with foliar feeding of nitrogen through spraying of nitrogenous fertilizers in place of top-dressing should be done in case of dry lands. 18. Judicious and careful application of micro-nutrients reduces occurrence of physiological or nutrients deficiencies diseases in crop plants and helps raising healthy crops. 19. Addition of organic manures should be done at least one in 3-5 years of time. 20. Weed growth should not be permitted in the cropped area during any part of the year.

32

21. In case of flooded fields or calcarious soils use of slow release nitrogenous fertilizers like U.F. 30, sulphur coated urea, urea super granules, neem coated or neem blended urea should be done so that loss of nitrogen can be minimized. 22. An appropriate plant protection measure and proper tillage practices should be adopted so that plants remain healthy and absorb the applied nutrients from the field.

WEEDS AND THEIR MANAGEMENTWeed . Plants are differentiated into crops which meet the needs of man and weeds which compete or interfere in mains affairs. Weeds are defined in different ways: (i) A weed is a plant growing where it is not wanted (ii) Weed is an unwanted plant (iii) A plant out of place. (iv) A plant that is extremely noxious, useless, unwanted or poisonous (v) Any plant or vegetation, excluding fungi, interfering with the objectives or requirements of people. Characteristics of weeds i. Most weeds are prolific seed producers. . ii. Dormancy in weed seeds is a continuous source of weeds on crop land. iii. Some weeds propogate vegetatively. iv. Dispersal of weed seeds exposes weeds to different ecosystems. v. Weeds are hardy and resist to adverse climatic, soil and disease conditions. vi. Evasiveness of weeds because of their bitter taste, disagreeable odour, spiny nature and mimicry. vii. Weeds are self sown plants. viii. Large number of weed species available to varied ecosystems. Losses caused by weeds (a) Land weeds i. Weeds compete with crop plants for nutrients, soil moisture, CO2, space and sunlight and reduce the crop yield and production efficiency. ii. Weeds reduce the quality of farm produce. iii. Loss of animal health. iv. Menace to human health, and working efficiency. v. Weeds damage to industry and public utilities. vi. Deterioration of aesthetic values. (b) Aquatic weeds i. They impede water flow in canals, channels, rivers, drainage etc. ii. They are menace to fishries. iii. They are water wasters. iv. They spoil the recreational value of water bodies. v. They pose pollution problems in water. Extent of yield losses caused by weeds The extent of losses due to weeds depends on intensity of infestation, time of occurrence and type of weeds. The yield losses in upland rice ranged between 66 to 92.8 33

per cent. Among the field crops sesame, cowpea, soybean and groundnut are most sensitive to weeds. The average losses due to weeds in different crops were 30 to 40 per cent in soybean, maize, potatoes, fodder and root crops and 15-20 per cent in other cereals. Crop-weed competition Weeds compete with the crop for different growth factors like nutrients, light, water and carbon dioxide. Many of the weeds also excrete certain chemicals into soil which inhibits the growth of crop plants. Critical Period of Crop - Weed Competition The basic idea of weed management is to provide curative treatment when economic damage is caused by weeds. For integrated weed management it is necessary to work the critical periods of weed competition and also necessity of weed free environment needed during the initial period of crop growth. This provides the active duration during which the presence of several cultivated crops in the plots is needed to be free of weeds. Critical periods vary in different crops due to variation in their growth habit and crop duration. Critical period of crop-weed competition and yield losses caused by weeds in different crops Crops Critical period (DAS) % reduction in grain yield A. Cereals Rice (direct seeded) 15-45 15-90 Rice (transplanted) 30-45 15-40 Wheat 30-45 20-40 Maize 15-45 40-60 Sorghum 15-45 15-40 Pearlmillet 30-45 15-60 B. Pulses Pigeon pea 15-60 20-40 Greengram 15-30 25-50 Blackgram 15-30 30-50 Cowpea 15-30 15-30 Chickpea 30-60 15-25 Peas 30-45 20-30 Lentil 30-60 20-30 C. Oilseeds Soyabean 20-45 40-60 Groundnut 40-60 40-50 Sunflower 30-45 30-50 Castor 30-60 30-35 Safflower 15-45 35-60 Sesamum 15-45 15-40 Rapeseed-mustard 15-40 15-30 Linseed 20-45 30-40 D. Commercial crop. Sugarcane 30-120 20-30 34

Potato Cotton Jute

20-40 15-60 30-45

30-60 40-50 50-80

35

Major crops, associated weeds and their recommended herbicides with time application: Name of Major weeds Name of herbicide Rate of Crop found selective herbicide application Wheat and Fumaria parviflora, For wild oats: Barley Melilotus spp, Triallate or Diallate 1.25 kg ai/ha Chenopodium album, For Phalaris: Vicia spp, Asphodelus Methabenzthiazuron 0.75-1.50 kg/ha tenuifolius, Spergula Metoxuron 1.5 kg/ha arvensis, Convolvulus Isoproturon 0.75 kg/ha arvensis, Avena fatua, For Isoproturon Phalaris minor, Poa resistant areas: annua, Polypogon spp. Sulfosulfuron 24.5 g/ha Clodinafop 60 g/ha Tralkoxydim 350 glha For broadleaved weeds: 0.25-0.50 kg/ha 2,4-D Rice Echinochloa colona, Echinochloa crusgalli, Paspalum distichum, Panicum spp., Cyperus spp., Ammania baccifera, Eclipta alba Cyperus spp, Digera arvensis, Phyllanthus nhruri, Euphorbia hirta, Trianthema monogyma, Solanum nigrum,Cynodon dactylon Same weeds as of maize Same weeds as of maize Cyperus rotundus, Cynodon dactylon, Euphorbia hirta, Commelina benghlalensis, Digera arvensis, Phyllanthus niruri,Chenopodium album, Sorghum halepense, Croton sporsiflora, Corchorus spp Cyperus rotundus, Butachlor/ Thiobencarb/ Pendimethalin Anilofos Pretilachlor Simazine or Atrazine 1.5 kg al/ha

and rate of Time of application PPI Post emergence treatment 3040 days after sowing -do

0.4 kg ai/ha 1.0 kg ai/ha 1-1.5 kg/ha

Maize

Within 2-3 days of transplanting in 4-5 cm standing water -do -do As preemergence or 7-15 days after sowing in 500600 l water/ha Pre-emergence or 7-15 days after sowing As pre-plant soil incorporation As preemergence -do Apply 9 days after planting

Jowar and Bajra Groundnut Sugarcane

Simazine or Atrazine Fluchloralin Pendimethalln Alachlor Atrazine or Simazine Metribuzin Dalapon Isoproturon + 2,4- D

0.5-1.0 kg/ha 1-2 kg/ha 2 kg/ha 1-2 kg/ha 1-2 kg/ha 0.75-1.5 kg/ha 0.5-1.0% directed spray 1-2 kg/ha + 0.25-0.30 kg/ha

Cotton

Trifluralin or

0.75-1.5 kg/ha

PPI

36

Pigeon Pea

Green gram and Black gram Cowpea Soybean Gram and Lentil

Cynodon dactylon, Eleusine spp, Celosia argentia, Sorghum halepense, Amaranthus spp, Corchorus spp, Trianthema monogyna Cyperus rotundus, Amaranthus spp, Celosia argentia, Sorghum halepense, Convoivulus arvensis, Solanum nigrum, Digora arvensis, Trianthema monogyna, Phyllanthus niruri Same as above

fluchloralin Pendimethalin

Pre-emergence 1.2-1.5 kg/ha

Pendimethalin Alachlor

0.75-1.0 kg/ha 1-1.5 kg/ha

Pre-emergence in 500-600 I water/ha

Pendimethalin Alachlor Same as above Alachior or Metolachlor Pendimethalin Fluchioralin or trifluralin Pendimethalin

0.50 kg/ha 1-2 kg/ha Same as above 1-2 kg/ha 0.50-0.75 kg/ha 0.75 kg/ha 0.75-1.0 kg/ha

Same as above Same as above Chenopodium album, Asphodelus tenuifolius, Fumaria parviflora, Ana galls arvensis, Cyperus rotundus, Melilotus spp., Vicia spp Cyperus rotundus, Cynodon dactylon, Euphorbia hirta, Eleusine spp., Trianthema monogyna, Phyllanthus niruri, Digera aivensis, Commelina benghalensis Chenopodium album, Fumaria parviflora, Spurgula arvensis, Anagallis arvensis, Cyperus rotundus, Vicia spp., Melilotus spp

Applied as preemergence in 500-600 I water/ ha Same as above Applied as preemergence PPI

Sunflower

Pendimethalin

1-2 kg/ha

Applied as preemergence

Mustard and Linseed

Isoproturon Trifluralin

0.75-1.0 kg/ha 0.50 kg/ha

Pre-emergence -do

37

IMPORTANT WEEDS (KHARIF)

Echinochloa crusgalli

Solanum nigrum

Digera arvensis

Tribulus terrestris

Achyranthus aspera

Eluesine indica

Euphorbia hirta

Dactyloctenum aegyptium Eragrostis japonica

Physalis minima

Xanthium strumarium

Trianthema portulacastrum

38

IMPORTANT WEEDS (RABI)

Poa annua

Oxalis corniculata Anagallis arvensis Polygonum plebijum Chicorium intybus Malva parviflora

Chanopodium murale

Vicia sativa

Fumaria parviflora

Polypogon monspeliensis Asphodelus tenuifolius Convolvulus arvensis

39

Circium arvense

Lathyrus aphaca

Phalaris minor

Avena ludoviciana

Chenopodium album

Rumex maritimus

Orobanchi aegyptiaca

Parthenium hysterophorus

Cornopus dydimus

Melilotus indica

Cynodon dactylon

Cyprus iria

40Cynadon dactylon Cyprus iria

Distinguishing characteristics between related crops and weeds Below given crops and weeds are of rabi season and are associated with each other. But because of their similar morphology it is difficult to identify them easily for physical and mechanical control. Hence, some of the peculiar characters of each is given below for their easy identification and control. Wheat Stem is hollow, no branching, seedling dark green in colour. Barley Stem is hollow, no branching, seedling light green in colour. Wild oats Stem is hollow, no branching, pale green purple dot found at the juncture of the tillers. Leaves are green in colour, slightly more rough than Phalaris. No serrations and hairs at the margin. Ligule is large and serrated. No auricles, hairs are found at the juncture of leaf sheath and lamina. Plant grows erect. Tillers do not branch. Produce 60-70 seeds per plant. Phalaris Stem is solid, branched, seedlings have purple colour at base up to 50 days of growth. Leaves are smooth, light yellowish colour with purplish green spots at juncture of lamina and leaf sheath. Ligule is the largest with smooth curve. No auricles, no hairs at the juncture of leaf sheath and lamina. Tillering is rossete type. Tillers branch. Produce 10,000 to 30,000 seeds per plant.

Leaves are dark green in colour with serrations at the margin of lamina. Leaves are rough and have hairs. Ligule is small. Auricles are small, hairy and stem is half clasped. Plant grows erect. Tillers do not branch. Produce 50-60 seeds per plant.

Leaves are light green in colour and smooth. No serrtions and no hairs at the margin. Ligule is small. Auricles are large, no hairs and stem is fully clasped. Plant grows erect. Tillers do not branch. Produce 50-60 seeds per plant.

Morphological differences in rice and Echinochloa spp. Rice Leaves have two auricles and a ligule. Plants are 100cm in height in dwarf varieties. Leaves are dark green in colour. Echinochloa spp. There are no auricles and ligule. Plants have generally more height than rice plants. Leaves are lighter in colour than rice.

41

Selection of herbicides Several herbicides are available in the market today and the selection of a herbicide depends upon weed flora (broad leaved, sedges, grasses, etc.) and time of application (before or after planting). A single herbicide can not control all weeds. Two or more herbicides may be mixed together (tank-mix application) to achieve broad spectrum weed control. If they are not compatible they may be applied one after the other after a gap of a few days (sequential application). Some formulations with mixture of herbicides: are also available (ready-mix) for ready use by farmers (e.g. Butanil is the mixture of butachlor and propanil, Almix is the combination of chlorimuron-ethyl and metsulfuron- methyl).Care may be taken while using herbicides in situations, where simultaneously more than one crop is grown (inter-or mixed cropping). Select a herbicide which is safe to all the crops grown. For example, choose atrazine for weed control in maize and pendimethalin for maize intercropped with legumes. Selection of an herbicide also depends on its availability in the market and the cost The following points may be considered for increasing the efficiency of herbicides and to reduce the cost of weed control Apply herbicides at recommended rate and time of application Apply pre-plant and pre-emergence herbicides on a well prepared field free from clods and crop or weed residues. Use low dose in light soil and higher dose in heavy soils. Ensure optimum soil moisture at the time of application, particularly with soil-acting herbicides. Lower herbicide dose integrated with hand weeding or hoeing is more effective and economical, than herbicide alone at higher dose. Take up spraying of herbicides on a calm, clear and sunny day for maximum benefit. Do not take up spraying, if the rain is expected in the next 4-6 hours. The performance of some of the herbicides can be enhanced substantially by adding adjuvants (e.g. surfactants like Teepol, Selwet, etc.) to the spray solution Apply post- emergence herbicides on the actively growing vegetation. Never apply when weeds are too small or when they are overgrown. Follow herbicide rotation (different herbicides in different years) and use herbicide mixture to prevent weed flora shifts and development of herbicide resistant weeds. Application of the herbicide Uniform application of the herbicide is very crucial for good weed control and for better crop growth. Often a very small quantity of the herbicide is required to be applied on a large area. Any deviation would result in serious consequences. While under-dosing would result in poor weed control, over-dosing may damage the crop. In order to apply the herbicide uniformly, one needs to calibrate the sprayer and calculate the herbicide requirement carefully. Herbicides are applied on area-basis (kg or L/ha) not by concentration basis (%) as is done in case of insecticides or fungicides. However in 42

controlling weeds in non-crop lands, aquatic ecosystem and in spot application, very often the herbicide is applied on concentration basis. Herbicide formulations Most herbicides are formulated as wettable powders (WP) or emulsifiable concentrate (EC) and aqueous concentrates which are diluted in water and applied with a sprayer. Granular formulations (G) are used directly mostly in submerged conditions. There is a growing practice amongst farmers to broadcast the mixture of other formulations of herbicides with sand, soil or urea, just before irrigation (as done with isoproturon in wheat) instead of spraying. Many small and marginal farmers in India do not have a sprayer, and it is natural for them to look for alternative methods to do away spraying. However, it should be pointed out that mixing of other formulations herbicides with sand, soil or urea to obtain granules is neither very scientific safe as the farmers invariably make these mixtures by bare hands. It is difficult to obtain uniform distribution in the field with sand application. Calibration of the sprayer Calibration is nothing but finding out how much area could be sprayed with the sprayer you have. The area sprayed is also dependent on the type of nozzle, spray pressure and the speed of application. The most practical way to calibrate the spray is by actually using it in the field. Spraying can be done by moving the spray lance from side to side using a flat fan nozzle or walk forward holding the spray lance one position using a flood jet nozzle. In both cases measure the swath width i.e., the width that is to be treated.Mark an area having width equal to the swath width. Keep the sprayer on a level ground and fill the water to a marked level. Carry out spraying on the marked area at a normal speed. Avoid skipping or overlapping. Refill the sprayer to the original level marked earlier.The quantity refilled is the quantity required to spray the marked area. Work out the volume rate/ha. Marked area 20 square meters Quantity of water used 1 litre Volume rate = (lXl0, 000)/20 = 500 L/ha or 200 L/acre With the same swath width and operating speed, the spraying could be undertaken to apply the herbicides in the field. The basic principle in calibration of a boom sprayer with more than one nozzle or tractor-mounted sprayer is also similar, the only difference being the flow rate all nozzles in a boom has to be taken into account. Calculation of herbicide requirement The product label and the literature supplied with the herbicide will provide details of herbicide name, active ingredient (a.i.), date of expiry, directions for use etc. It must be read before using the herbicide. It is particularly important to note the strength of the product (a.i.) as the same herbicide may be sold under different trade names with varying amounts of active ingredient. For example, isoproturon is available at 50 and 75% formulations. For this reason only, the 43

recommendations are normally made on kg a.i. basis. Even in liquid formulations the herbicide present is mentioned in g/L. The amount of commercial formulation of the herbicide required can be calculated by the following formula: Commercial product (kg/ha) = Dose in kg a.i. /ha X 100 % a. i. in the product Isoproturon is available as 75% WP and 50% WP. If the recommended rate of application is 0.75 kg ai/ha then the amount of commercial product required is:50% WP product = 0.75 X 100 = 1.50 kg/ha 50 75% WP product = 0.75 X 100 = 1.00 kg/ha 75 Paraquat is to be applied at 0.5 kg a.i. /ha. The herbicide is available as Gramoxone (commercial name of paraquat) which contains 25% paraquat. The quantity of Gramoxone required is = 0.50 X 100 = 2.0 litre/ha 25 Making stock solution In order to apply herbicide uniformly in the entire required area, it is advisable prepare stock solution of the herbicide. Suppose; in order to apply herbicide uniformly in the entire required area, it is advisable prepare stock solution of the herbicide. Suppose; Area to be treated = 1 ha (2.5 acres) Sprayer capacity = 15 litre Sprayer calibration = 450 litres / ha Then, 450 = 30 15 that is 30 refills are required to spray one hectare area. In which case, it is advisable to dissolve the required amount of herbicide as obtained in calculations 1, 2 or 3 in 30 measures (could be a glass tumbler, plastic mug or a container) of water which becomes the stock solution. Now add 1 measure of this stock solution to sprayer tank containing 15 L water, stir it and spray as suggested earlier. Alternatively one can dissolve the entire quantity of herbicide in 450 liters of water contained in a big container and use this solution directly for spraying. Tips for proper application of herbicides The spray tank should be at least one-third full with clean water before any concentrate is added and the contents well mixed while the concentrate is being put in slowly. Wettable powder formulations should be made up into a paste and then diluted before adding to the spray tank. The spray tank should always be emptied completely before refilling to avoid altering the concentration of the spray. 44

The spray should be made as required to avoid storing unused diluted spray. Should there be a short delay in application, stir or agitate the contents in the sprayer just before use to prevent settling down of the herbicide at the bottom. Wettable powder formulations are more prone to settling down than liquid formulations. Pressure should be built up before the control lever or tap is moved to the 'spray' position (in case of tractor-mounted sprayers). Never operate the sprayer while standing still. In tractor-mounted sprayers open the nozzles only when tractor starts moving. Never when it is stationary. Do not apply herbicide, when the tractor is taking turns. Accurate swath matching is a must. Spraying along the rows can help in easy swath matching. With tractor-mounted sprayers adjust the height of spray boom for uniform application. Pumping should stop as soon as the tank is empty and a mark should be left in the field to indicate from where the spraying should recommence. It is worth dividing the area to be treated into convenient units for uniform spraying particularly for pre-emergence application. Do not apply a herbicide, if a crop susceptible to that herbicide is growing downwind of the area to be treated. Volatile esters of herbicides should be avoided under such a situation. Early morning is often a good time to spray when the wind is gentle. It is advisable to use a separate sprayer for spraying hormone type herbicides (MCPA, 2, 4-D, etc.). Small traces of herbicide residues in the sprayer can cause pytotoxicity in susceptible crops. Avoid spraying foliage-active herbicide if rains are expected in the next two hours or so. However , a light rain or irrigation is often beneficial for a soil-active herbicide. Apply herbicide using a sprayer with 500-600 L/ha water. Flood jet or flat fan nozzle should only be used for spraying the herbicides.

Aftercare of sprayers and nozzles Wash the sprayer thoroughly with water before and after each use. Any blocked nozzle should be changed or washed in clean water. Do not blow through blocked nozzle with the mouth or use hard objects (such as knives, wires etc.) as they may alter spray output and droplet size. Nozzles should therefore be checked often and may require replacing once in a year or so. When sprayer is to be stored, it should be thoroughly cleaned by adding detergent the water and rinsing several times to remove all traces of the detergent before storing. The tank should be drained and left with the lid off to allow air circulation. 45

All bearings and hinges should be oiled or greased and wheeled machines should be put on blocks with the tyres out of sun. Hoses can be removed and stored hanging vertically to prevent rodent damage. Safe handling of herbicides It is important to read the label before use and follow directions and precautions properly. The label tells what the herbicide is, lists the amount of active ingredient and gives recommendations and precautions for use. Most herbicides are potentially dangerous particularly in concentrated form but they are not likely to cause injury if used properly and if recommended precautions are observed. The dangers associated with mishandling and misapplication of herbicides may include possible injury to the operator and handler, poisoning live stock, damage to desirable plants, damage to equipments and poisoning fish and wild life etc. The following points may be taken note of in preventing the abuse of herbicides. Avoid prolonged contact with the skin, breathing vapours or dusts and splashing herbicide solution in to eyes or mouth. Wash off with soap water any herbicide spilled on the body. Do not smoke or eat while working with chemicals. Do not spray against the wind. Cover the face with a cloth while spraying. If unusual symptoms such as dizziness, nausea or skin rashes appear, seek medical advice at once. Dispose of empty containers immediately. Mutilate them to avoid re-use and bury the remnants deep in an isolated area. Do not use them for domestic purposes. Avoid contaminating water supplies with herbicides. Store unused herbicides in original containers in a locked storage area away from food grains and children. First aid In case of accidental ingestion, induce vomiting by putting the forefinger at the base of the palate or by administering a warm glass of water with a spoon of common salt. Give a glass of water containing medicinal charcoal. In case of severe symptoms of toxicity, call for a doctor immediately. Keep the patient in fresh air.

46

DRYLAND AGRICULTUREGrowing of crops under rainfed conditions is known as dryland agriculture. Depending upon the amount of rainfall received dryland agriculture can be grouped into three categories: 1. Dry farming Dry farming is the cultivation of crops in areas where rainfall is less than 750 mm per annum. Prolonged dry spells during crop period are most common. Crop failures are more frequent under dry farming conditions. Dry farming regions are equivalent to arid regions and moisture conservation practices are important in this region. 2. Dryland farming Cultivation of crops in areas receiving rainfall above 750 mm is known as dryland farming. Dry spells during crop period occur, but crop failures are less frequent. Dryland farming areas are grouped under semi arid regions. Adoption of soil moisture conservation practices and also provision of drainage especially in black soils are necessary. 3. Rainfed farming Cultivation of crops in regions receiving more than 1150 mm rainfall is known as rainfed farming. It is practiced in humid regions where crop failures are rare and drainage is the most important problem. Distinguish dryland vs rainfed farming Constituent Dryland farming Rainfed farming Moisture availability to Shortage Enough the crop Growing season (days) < 200 > 200 Growing regions Arid and semiarid as well as uplands sub-humid and humid of sub-humid and humid regions region Cropping system Monocrop or intercropping lntercropping or double cropping Constraints/ problems wind and water erosion water erosion and drainage The average values of different soil moisture constants of different soil types Soil type Sandy Sandy loam Loam Clay loam Clay Field capacity (% by weight) 5-10 1 0-18 18-25 24-32 32-40 Permanent wilting point (% by weight) 2-6 4-10 8-14 11-16 15-22 Available soil water (Cm/m depth) 5-10 9-16 14-22 17-25 20-28

Major problems of dry farming (I) Inadequate and uneven distribution of rainfall (II) Late onset and early cessation of rains (III) Prolonged dry spells during the crop period (IV) Low moisture retention capacity and low soil fertility 47

CROPPING SCHEMEPreparation of cropping scheme On a farm, various crops are grown in various ways with respect to time and space on individual fields. The relative area allocated to each crop on the farm depends on availability of resources, market trends, domestic needs and certain other factors like location of farm, transportation facilities, distance from the agricultural industries etc. Therefore, a proper planning of the crops to be raised on the farm is important to get higher profit. In this context it is important to know certain terms used in crop planning. 1. Cropping systems: These are the ways or systems according to which various crops are grown on a given piece of land in a given period of time. The cropping systems can broadly be divided into two types, monoculture (monocropping) and multiple cropping. In monoculture same crop is grown continuously (year after year) on same piece of land. This system is neither common nor desirable as it impairs the soil health, increases incidence of crop pests and decreases the crop yield. In multiple cropping system two or more crops are grown in a year or a season on a given piece of land. This system is most common as it gives more output per unit area per unit time. Growing two or more crops on the same field in a year is achieved by two ways, either by growing compatible crops together, called mixed cropping and intercropping, or by growing the suitable crops in a sequence (one after the other), called sequential cropping. In mixed cropping all component crops are sown almost at the same time in the same field and plant population of each crop in the field is reduced proportiona