There are several established approachable to eco friendly farming system. A common thread on all school is an emphasis on biological system to supply fertility and pest control rather than chemical inputs. The most widely recognized alternative farming system. Modern organic evolved as an alternative to chemical agriculture in the 1940s, largely in response to the publication of J.I Rodale in the U.S Lady, Eve Balfour in English, and Sir Albert Howard in India. In 1980, U.S.D.A released a landmark report on organic farming.
The Defined Organic Farming as:
Organic Farming System:
Is defined as the production system in which avoids or largely exclude the use of synthetically compounded fertilizers, pesticide, growth regulator and livestock feed additives. To the maximum extent feasible organic farming system realy upon crop rotations, crop residues, animal manures, legumes, green manure, off- farm organic wastes and aspects of biological pest control insets, pest weeds etc.
Organic farming methods are widely used in underdeveloped and developing countries, largely because of ecomics and a lack of chemicals. However, they are becoming more widely accepted in developed countries as a reaction or factory conditions.
Problems of Present Day Agriculture:
The Green revolution technology, particularly in India, led to many fold increase in food grains production, but has made demands on water, fertilizer and farm power. The effect of intensive cropping has resulted in deteriorating soil tilth and decreased organic matter content high level of chemical inputs is increasing pollution hazard and result further degradation of soil health, the increased use of agro- chemical is polluting water and atmosphere and thus effect on crop production, and animal and reflect on human health.
Some Important Problems are:
1. Soil degradation.
2. Decreasing soil fertility.
3. Water and environmental pollution.
4. Water management problems like:
a) Problem of brackish ground water.
b) Runoff and flooding.
c) Salinization Problem.
d) Low irrigation efficiency.
Why Organic Farming not Adopted on Large Scale?
Cause of low adoption:
1. Chemical are easy to use and less costly.
2. The benefit of organic practices is not seen immediately.
3. Large quintiles of organic inputs are required.
4. Difficult to get organic fertilizer.
5. Unorganized market for organically grown produce.
6. Preference to consume organic food is yet not established.
7. Economic loss to transition (from traditional agriculture to organic agriculture).
8. No experimental evidence on the cost benefit ratio of organic farming.
9. Government effort to propagate.
10. Scientific research is also scare.
There are at least three options available in organic farming they are:
1. Pure organic farming.
2. Integrated green revolution farming.
3. Integrated farming system.( IFS).
1. Pure Organic Farming:
This excludes the use of inorganic manures and biological pest control methods. It all the NPK requirement is to be supplied in the form of organic either as farm or town compost or green manure, the quantity of organic required will be huge. But large potential of organic resources remains untapped in the country. Nearly 750 millions tones of cow dung, 250 millions tones yielding crop varieties and hybrid and mechanization of labour are retained. But much greater efficiency on the use of these inputs is obtained to limit damages to the environment and human health. For this purpose, some organic techniques are developed and combined with the input technology in order to create integrated system such as ‘Integrated nutrient management ‘ ( INM), ‘Integrated pest management ‘and biological control method, which reduce need or chemicals. Modern biotechnology is also employed to developed higher yielding, pest resistant crop varities.
2. Integrated Farming System:
The third option in Organic farming is the low input organic farming, in which the farmers have to depend on local resources and ecological process, recycling agricultural wastes and crop residues.
The Following Categories have been Suggestion:
1. External quality freedom from pest and disease damage freshness and colour.
2. Technological quality: Improved properties of storage and processing.
3. Nutritional / physiological quality: Increased content of valuable nutrient and other agricultural chemical residues.
4. Environment quality of the system of production, with regard to the organization of crop and livestock and management of farm resources, in such a way that they harmonize rather than conflict with natural system.
This system merits consideration on the ground that most of the ills of modern day agriculture are avoided. Use of agro chemical is forbidden. There is emphasis on build up or organic matter in the soil, there by activating biological activity. Soil is treated as a living organism. Maintenance of favorable soil structure and development and use of crop rotation that improve soil fertility, control pests and disease, pest and diseases, pests and weeds are adopted. The major difference between organic and conventional farming is the almost exclusive reliance of the organic farmer on organic matter for supply of nutrients.
As a consequence of conventional agricultural practices, soil erosion and air pollution may occur. Eroded soils run into reservoirs, clogging water ways, etc, thereby existing an off farm impact. In areas where soils are heavily fertilized soils omit 2 to 10 times as much nitrous oxide as unfertilized soils and pasture.
Conservation of wild life habitat and rural landscape to agricultural use may lead to loss of biodiversity and degradation of landscape an off farm impact having long term consequence on productivity and sustainability. In view of the impact that conventional agricultural practices have, what is needed is an ecomically and environmentally efficient agriculture.
1. Cropping (Rice- fich – poultry- mushroom)
2. Fish culture.
4. Mushroom production.
5. Cropping 0.36 ha.
6. Fish pond 0.04 ha.
This farming system (IFS) was compared with conventional cropping normally followed in the region. Rice – Rice – green gram and rice – rice – green manure (0.20 ha).
1. Fish pond area of 0.04 ha with 1.5 m depth.
2. Diff. finger lings of diff. fish species with total of 7500/ ha.
3. Harvesting of fish commenced from tench month. A poultry shed at corner of fish pond( shed 2.2 m2).
4. Free fall of poultry dropping into the fish pond (Twenty Bapcock chicks of 18 weeks old reared).
5. The feed components were purchase only in 1 st year of cropping.
6. The birds started laying eggs around 22 nd weeks up to 72nd when they were culled out.
7. A mushroom shed of 5 * 3 m was constructed with local materials. Oyster mushroom was produced utilizing rice straw as the base material.
Economics- on an average net profit of Rs. 11, 755 was obtained in rice – poultry- mushroom system as compared to Rs. 6, 335 only from conventional system of cropping. Additional employment of 174 man – days was generated due to IFS.
IFS – Tamil Nadu – Cauvery delta Zone (Crop – poultry- fish system).
Farmers of this zone are practicing monocropping of rice for two season followed by a rice fallow pulse. Among the different allied activities, pisciculture plays an important role in this zone since water is available in the canal about 7 – 8 months. Poultry farming is another feasible enterprise. By combing the enterprises of poultry – cum fish culture with rice cropping system the economic status of the small and marginal farmers could be improved.
Components: – One ha area has been selected.
– 0.04 ha area for fishpond
– Improved cropping as rice- rice cotton (0.76 ha) and
– Rice- rice – maize (0.20 ha).
Maize being a major constituent of poultry feed was included in the system. This system compared with the existing practice of rice- rice – black gram
Poultry unit: – 50 Bapocock’s, Bu 300 hybrid layer bird of 21 weeks age were maintained till 43 Weeks.
– 100 g/day/ bird through maize, rice bran, groundnut cake.
Fish culture: Ponds near to poultry shed. Different fingerlings of fish in ponds, with density of population maintained were 10000 fingerlings / ha. The fish were harvested after six and half months.
Economic: A net return of Rs. 17,200 was obtained by integrating different enterprises by introducing poultry – cum – fish culture with cropping a total employment of 385 man- days was generated.
Integrated Farming System (IFS) for Irrigated Situations (Garden lands):
A model integrated farming system to suit the small and marginal farmers of garden land condition was studies at TNAU, Coimbatore, during 1988- 1993 ( Rangaswami et al. 1995) An area of one ha was selected for IFS and compared with conventional cropping system( CCS).
Components of IFS:
Area ( ha)
Cotton = green gram maize + fodder cowpea- Bellary onion
The above integrate system was compared with the conventional cropping system of cotton sorghum- finger millet in 0.20 ha area.
Economic returns from the system: Maize flour, cottonseed and wheat bran obtained from the crop components were recycled for preparing dairy feed from the second year. About 45.5 t of to the animals. Dung was recycled for the biogas plant. Mean revenue of Rs. 34600/ ha was realized in IFS as compared to RS. 13950 obtained in CCS. Employment opportunity was also enhanced to the tune of 770 man- days per year under IFS as against conventional cropping.
III) Integrated farming system (IFS) for Dry Land based system: Integrated farming system for dry lands suggested for Coimbatore and Aruppukottai, Tamil Nadu, are described below:
Model for Coimbatore, Tamil Nadu (mean Annual rainfall; 640 mm).
Crop Components for One Hectare:
Area ( ha)
Sorghum + cowpea both grain purpose
Sorghum + cowpea both fodder purpose
Leucaena ( tree fodder)+ Cenchrus ( grass fodder)
Aracia Senegal ( tree fodder) + grass
Prosonic cineraris ( tree fodder ) + grass
Animal Components: Telicherry goat: 6 (5 female + 1 male – stall fed)
Conventional cropping system = 0.20 ha (sorghum+ cowpea- grain purpose).
The animal components, tell cherry goat, numbering 6 (5 female+ 1 male) were kept in a shed ( 6 * 4 m ). The goals were stall fed form the cropping components. Two kg each of green and dry fodder and 100 g of concentrate were given to each animal. At the end of second year. All the 4 male goats were disposed retaining one number. From the end of third year onwards, 20 female and one male were retained and remaining disposed. The litter form the goat shed was used for composting and recycled as manure. A farm pond was dug in an area of 300 m2 and the rain water harvested was utilized for pot watering the tree saplings.
Economic returns from the system: men additional revenue of Rs. 3750ha / year was obtained from IFS over CCS. The employment generation under IFS was 153- man days/ ha / year whereas it was only 40- man days/ ha/ year in the CCS (sivasankaram et al. 1995).
IFS for island Ecosystem:
Integrated farming system models have been developed for the Andaman and Nikobar Islands –
1.Coconut – cum – fodder- cum – milch cattle: Mixed farming by raising fodder grass coconut has been founded profitable; grass in coconut has been found profitable, grass like hybrid Napier or leguminous fodder like Stylo in Coconut garden can support 4- 5 dairy animals. Animal supply large qualities of cattle manure applied to coconut garden improve the soil fertility.
2. Coconut – cum fish culture in salt affected lands: Coconut grows successfully even in salt affected paddy fields if the fields are within the approach of brackish water. The bunds of fields at water entrance gate should be raised to maintain the required level of water. Field bunds should also be raised a per the requirement. Water will be exchanged and thus fish raising can be taken up together with coconut in dry period. In rainy season, salinity tolerant rice varities could be cultivated in the same field with coconut and fish culture.
3. Fruits- fodder- milch cattle:The space available between the fruit trees can be utilized for growing fodder crops such as cow pear, rice bean, germ gram and black gram. The fodder could be used for feeding the cattle and cattle manure could be applied to the fruit trees and fodder crops.
In agriculture, crop husbandry is the main activity. The income obtained from cropping is hardily sufficient to sustain the farm family through out year. Activities such as dairying, poultry, fich- culture, sericulture, biogas production, edible mushroom cultivation, agro- forestry, agri- horticulture etc. assumes critical importance in supplementing their farm income. Assumed regular cash flow is possible when cropping is combined with other enterprises. Judicious combination of enterprises keeping in view of the environment condition of a locality will pay grater dividends. At the same time it will promote effective recycling of residues/ wastes.
Integrated farming system seems to be the answer to the problems of increasing food production. For increasing income and for improving nutrition of the small scale farmers with limited resources without any adverse effect on environment and agro- eco-system. In a cropping system. The amount of byproducts can be as high as or higher than marketable produce. This may go to waste if not utilized in an animal waste component and to reduce the cost of production of the economic produce of component two and finally to entrance the net income of the farm is whole.
Livestock is the best complementary enterprises with cropping, especially during the adverse years. Installation of a biogas plant in crop- livestock system will make use of the wastes, at the same time provides valuable manure and gas for cooking and lighting.
In a wetland farm, there are greater avenues for fishery, duck farming and buffalo rearing; utilizing the rice straw and mushroom production can be started.
Under irrigated condition (garden lands) inclusion of sericulture, poultry and piggery along with arable crop production is an accepted practice. The poultry component in this system can make use crop the grains produced in the farm as feed. Pigs are the unique components that can be reared with the waste which are unfit for human consumption.
In Rainfed farming, sheep and goat rearing form an integrated part of the landscape, sericulture can be introduced in Rainfed farming provided the climatic condition permit it.
Agro- forestry (silvi- culture and silvi- horticulture) is \the other activities, which can vbe included under dry land condition. In the integrated system, selection of enterprise should be on the cardinal principal that there should be minimum competition and maximum complementary effect among the enterprises.
1. Upland Irrigated Farming Systems: Additional income can be generated by enterprises like dairy biogas and silvi culture to the usual cropping systems. Two to three milch cows can be maintained from one ha. Straw. Recycling of farm and animal wastes through biogas unit can produce cooking gas for family use. Several such integration can greatly increase farm income, besides providing work to family members all through the year.
2. Farming System Under Lowland: common cropping system in rice based system, especially under agro climatic condition of south India is rice- rice – pulse, modified cropping system includes crops like maze, groundnut, sesamum, rice – fish – poultry culture system appears to more remunerative, poultry droppings from the poultry shed placed well above the farm poned meets the needs of fish in the ponded water, Water in the pond can be used for irrigating the crops. About 500 layer chicks are sufficient and excreta can meet the feed requirement of 7, 500 polyculture fingerlings in one ha of poned water rice- fish system is also remunerative.
3. Rainfed Farming Systems: Environmentally sustainable dry land farming systems emphasis conservation and utilization of natural resources. Agronomic practices of conservation, tillage and mulch farming, rotational cropping use of legumes and cover crops for improving soil fertility and suppressing weeds and efficient use of cattle manure are some of the components of sustainable farming systems.
For above regulation sound land use policy is necessary to tackle the problems of deteriorating natural resources, like soil and water. Majority farmers mainating work animals, milch animal, chicks, sheep, goats etc. with crop production. Farmers approaching farming systems, but benefits from these system is low, because of non- educating and also due to non- adoption of improved technology.
Factors for Determing the Fertilizer Schedule are:
1. Soil supplying power.
2. Total uptake by crops.
3. Residual effect of fertilizers,
4. Nutrients added by legume crops.
5. Crop residues left on the soil.
6. Efficiency of crops in utilizing the soil and applied nutrients.
1. Soil Supplying Power:
Growing different crops during different seasons alters the soil nutrient status, estimated by soil analysis at the beginning of the season. The soil supplying power increases with legume in rotation. Fertilizer application and addition of crop residues. The available nitrogen and potassium in soil after groundnut are higher to initial status of the soil. But after pearl millet, only potassium status in the soil is improved and no changes in P.
2. Nutrient Uptake by Crops:
The total amount of nutrients taken by the crops in one sequence gives an indication of the fertilizer requirement of the system. The balance is obtained by subtracting the fertilize applied to crops that nutrient taken by the crops.
3. Residual Effect of Fertilizers:
The extent of residues left over in the soil depends on the type of fertilizer used. Phosphatic fertilizer and FYM have considerable residue in the soil, which is useful for subsequent crops. The residues left by potassium fertilizers are marginal.legume effect: Legumes add nitrogen to the soil in the range of 15 to 20 kg/ha. The amount of nitrogen added depends on the purpose. Green gram grown for grain, contributes 24 and 30 kg N respectively to the succeeding crop. Inclusion of leguminous green manures in the system add 40 kg to 120 kg N/ha. The availability of phosphorous is also increased by incorporation of green manure crops. Potassium availability to subsequent crop is also increased by groundnut crop residues: crop residues add considerable quantity of nutrients to the soil, cotton planted in finger millet stubbles benefits by 20 to 30 kg/ha due to decomposition of stubbles. Deep rooted crops- cotton, red gram absorbs nutrients from deeper laers. Leaf fall and decomposing add phosphorus to op layers crop residue contain high C: N ratio like stubbles of sorghum, pearl millet temporarily immobile nitrogen. Residue of legume’s crop contains low C: N ratio and they decompose quickly and release nutrients.
Efficiency of crops: jute is more efficient crop for utilizing of nitrogen followed by summer rice, maize, potato and groundnut in that order. Phosphorus efficient crops, jute > summer rice> Kharif rice> potato > groundnut > maize. Groundnut is more efficient in potassium utilization followed by maize, jute, summer rice, Kharif rice, and potato.
Fertilizer recommendation should be based on cropping system e.g. in wheat based cropping system an extra dose of 25% nitrogen is recommended for wheat when it is grown after sorghum, pearl millet. When wheat, after pulse crop needs 20 to 30 kg less nitrogen per hectare. Phosphatic fertilizers are added through green manure crops, not to apply phosphates to succeeding wheat crop. In rice based cropping system consisting of rice- rice in Kharif and rabbi and sorghum, maize, finger millet, soybean in summer it is sufficient to apply phosphorus and potassium to summer crops only while nitrogen is applied to all the crops. Thus, following system approach in fertilizer recommendation can save lot of fertilizer.
4. Water management:
There is no carry over effect of irrigation as in case of fertilizer, rice – rice is efficient cropping system for total yield, but it consume large amount of water especially in summer. If water is scare in summer instead of rice, groundnut is used in cropping system.
Method of irrigation: the layout should be so planned that most of the crops can be suitable, in rice- rice- groundnut system; rice is irrigated by flood method, while groundnut by boarder strips.
In cotton – sorghum- finger millet system, cotton, sorghum by furrow method while finger millet checks – basin method is adopted.
More remunerative and less water consuming crop rotation have standardized have been standardized at different location of India. Rice- mustard-green gram, rice- potato- green gram rotation were found more water efficient systems at memari in Memari in W.B under high level of irrigation in tarai region of U.P, rice-lentil and rice-wheat cropping system were found better. Pre monsoon groundnut-rabi sorghum sequence was highly remunerative with high water use efficiency compared to sugarcane alone in M.S when irrigation water is not limiting. Under limited water supply, however, rice – chickpea- green gram and rice- mustard – green gram are more remunerative with high water use efficiency.
5. Pest and Diseases:
Pest and diseases infestation more in sequence cropping due to continuous cropping, carry over effect of insecticides is not observed.
6. Weed management: weed problems observed individual crop, and weed shift occur and their carry over effect of weed control method on succeeding crop.
Weeds are dynamic in nature, generally broad- leaved weeds occur in wheat occur in wheat at later stage and 2, 4 D is applied as post emergence herbicide to control them. In rice- wheat system, canary grass (phallaris minor) is a menace for wheat crop. Other weed seed species are decomposed and loss viability, but Phataris minor seed do not loss viability. When sown in rice stubble is heavily infested with Phalaris minor. In cotton- sorghum-finger millet sequences cropping with zero tillage weeds are controlled by herbicide in two rotations.
Herbicide applied to the previous crop may be toxic to the succeeding crop. Higher dose of Atrazine applied to sorghum crop affect germination of succeeding pulse crops. Herbicide recommendation should be depends on succeeding crops, ploughing before the planting season helps to kill most of the weeds.
In sequences cropping crop can be harvested at physiological maturity stage instead of harvesting maturity. The field can vacate one week earlier. Because of continuous cropping the harvesting time may coincide with heavy rains and special post harvest operations, like artificial drying, treating the crop with common salt etc. are practices to save the produce. Integrated farming system, components and its advantages.
India with 2.2 percent of global geographical area support more than 15 percent of the total world population, 70 percent of who depends on agriculture. It is also support nearly 15 percent of the total livestock population of the world.
As of now, out of 328.73 ha of geographical areas approximately 18 percent is forest only 13.5 percent is not available for cultivation. Total problems areas constitute 173.65 million ha, which include areas subjected to wind and water erosion ( 145 million ha) water – logged areas ( 8.53 million ha), alkali soils ( 3.58 million ha), saline and coastal sandy areas (5.50 million ha), ravines and gullies ( 3.97 million ha ), shifting cultivation ( 4.91 million ha ) and reverie torrents 2.73 ( million ha). Besides 40 million ha are prone to flood and 260 million ha. Is drought prone. Thus the net sown area is 136.18 million ha. Is drought prone. Thus, the net sworne is 136.18 million ha (41.42 percent of the total geographical area) (subbing et.al, 2000)
Unlike industries, agriculture is practiced by 105 million farm families who live in 0.6 million village. More than 40 percent of them are below the poverty line. Nearly 85 million farm families belong to small and marginal categories. Only 25 to 30 % of the modern agricultural technology has reached the farmers. This is often because the technology has not been consistent with the condition with condition of the farm situations. Since there is no further scope for horizontal expansion of land for cultivation, the only alternative left is for vertical expansion on space and time particularly for small and marginal farmers (constituting 76% farming community) who do not have much of reasons, especially in rain fed areas. The new farming system research strategy should, therefore to develop technology with participatory approach of farmers.
Agronomic considerations for different cropping system are different due to inclusion of more than one crop as in intercropping or sequence cropping system. Thus, principal involved in management of 1/c and sequence system are different.
Intercrop is practiced with two objectives:
1) To get additional yields through and intercrop as bonus and
2) To avoid risk.
Management of Intercropping Systems:
In intercropping system crops are grown simultaneously. Management practices aim to provide favorable environment to all the component, exploit favorable interaction among the component crops and minimize competition among the components.
1. Seedbed Preparation: The objective of land preparation is to establish an ideal zone for the seedling that minimizes the stress. Potential stress condition include inadequate or excess moisture, unfavorable temperature for a given species, soil crushing weeds, residue of preceding crop and insect or pathogen attack. Important of seedbed is the same in both conventional (monoculture) and in multiple cropping. Seedbed preparation depends on the crop. Deep rooted crops responds to deep ploughing while for most of cereal shallow tillage is sufficient. The crops with small seed required fine seedbed, cotton, and maize, planted on ridges, certain crops on flat seedbed. Since more than one crop in intercropping, the seedbed preparation is generally prepared as per the needs of base crop. Sugarcane planted in furrow and intercrop sown on ridges, certain crops on flat seedbed. Since more than one crop in intercropping, the seedbed preparation is generally prepared as per the needs of base crop. Sugarcane planted in furrow and intercrop sown on ridges. In Groundnut + red gram intercropping system, flat seedbed is prepared for sowing crops. However, ICRISAT is recommending broad bed and furrow for black soils. In rice + maize intercropping system, ridges and trenches are formed. Maize is planted on ridges and rice in trenches.
2. Varieties: The varieties of component crop in intercropping system should be less competing with the base crop and peak nutrient demand period should different from the base crop. Maturity period between two components is minimum of 30 days. Hybrids varieties of sorghum like CSH -6, CSH -9 are suitable for intercropping with long duration variety of red gram like C11 and LRG 30 because of wider gap between maturity periods. The varities selected for intercrop should be have thin leaves, tolerant to shading and less branching. If the base crop is shorter than intercrop, the intercrop should be compact with erect branching and its early growth should be slow. The characteristics of the base crop should be as in sole crop.
3. Sowing: practices of sowing are slightly altered to accommodate inter- crop in such a way that it cause less competition to the base crop. Widening inter row spacing of cereal component to accommodate more rows of component legume crop improves legume yield and efficiency of the intercrop system. Sowing of base crop is done either as paired row, paired – winder row or skip row of base crop are brought close by reducing inter row spacing. The spacing between two pairs of rows is increased to accommodate the inter crop. Such row arrangement of component crops within the rows improves the amount of light transmitted tio the lower component crop, which can enhance legume yield in cereal legume intercropping system.
For example – the normal row spacing of Rainfed is 30 cm the row spacing is reduce to 20cm between paired rows and 50cm spacing in two in two pairs. The spacing in paired row planting designed as 20/50 cm indicated that the spacing between two rows in pairs is 20 cm and among the pairs 50cm.
Similarly, pearl millet is planted with row spacing 30/60 cm in paired row planting. These changes in crop geometry do not alter the yield of base crop, but intercrops are benefited to some extent. Or when alternating pairs of sorghum rows 90 cm with two rows of an associated legume, Singh (1972) found that LER was greater compared at 60cm between rows with two rows of the legume in between Planting in fixed ratio of intercrop is most common. The intercropping system of groundnut + red gram is either in 5:1 or 7:1 ratio and sorghum + red gram in 2:1 ratio. In these cases the normal three tined or four seed drill can be used without any modification. The hole pertaining to intercrop row in the hopper is closed with a piece of clh in that row, intercrop is sown with alkali or kera.
For higher yields, base crop population is maintained at its sole crop population and intercrop population is kept at 80 percent of its sole crop population.
Relative sowing time of component crop is important management variable manipulated in cereal- legume me /C system but has not been extensively studied. Sowing may be staggered to increase the temporal difference, which might result in higher yield advantage. (Singh et el.1981).
4. Fertilizer Application: The nutrient uptake is generally more in intercropping system compared to pure crops. When the legume are associated with cereal crop in intercropping system, legume supplement a portion of nitrogen required of cereal crop; the amount may be of 20kg/ha by legumes. Application of higher dose of nitrogen to the cereal + legume intercropping system not only reduce the nitrogen fixation capacity of legumes, but also growth of legume is suppressed by aggressive cereals owing to fast growth of cereals with increased availability of nitrogen, cereal + legume intercropping, therefore is mainly advantageous under low fertilizer application.
Considering all the factors, it is suggested that the nitrogen dose recommended for base crop as pure crop is sufficient for intercropping system with cereal + legume or legume + legume. With regards to phosphorus and potassium, one eighth to one fourth of the recommended dose of intercrop is also added in addition to recommended dose of base crops to meet the extra demand. Basal dose of nitrogen is applied to rows of both components in cereal + legume inter crop. Top dressing of nitrogen is done only cereal rows. P & K are applied as basal dose to both crops.
5. Water Requirement: The technique of water management is the same for sole cropping and intercropping or sequential cropping. However, the presence of an addition crop may have an important effect on evapo- transpiration. With proper water management, it is possible to grow two crops where normally only one crop is raised under rain fed condition. Intercropping system is generally recommended for rain fed crop get the stable yields. The total water requirement of I/c dose not increase much compared to sole cropping. At ICRISAT, the water requirement of sole sorghum and intercropping with red gram was almost similar (584 and 585 mm, respectively). However in a more competitive crop like onion as intercropped in groundnut increase the total W.R by about 50mm. the total water used in intercropping system is almost same as in sole crops, but yields are increased. Thus water use efficiency of intercropping is higher than sole crops.
Scheduling of water: if one of the crop is irrigated based on its requirement, the other crop may suffer due to excess water stress, sometimes leading to total failure of crop. In cotton black gam I/C system, cotton is irrigated once in 15-20 days. The intercrop black gram is often affected by excess water and gives poor yield. In such situations, skip furrow method of irrigation is advocated. Scheduling irrigation at IW/CPE ratio of 0.60 to 0.80 or irrigation at one bar soil moisture tension is suitable for most of the systems.
6. Weed Management: Generally it is believed that intensive cropping reduce weed problems. Weed infestation depends on the crop, plant density and cultural operation done. Weed problems is less in intercropping system compared to the sole crops. This is due to more complete crop cover and high density available in I/C cause severe competition with weeds and reduce weed growth. The weed suppressing ability of intercrop is dependent upon the component crops selected, genotype used, plant density adopted, proportion of component crops, their spatial arrangement and fertility moisture status of the soil.
Experiment carried out at ICRISAT, Hyderabad, indicated that there was 50- 75 % reduction in weed infestation by intercropping. Pigeon pea + sorghum I/C system, which is extensively practiced in Karnataka, M.S and A.P is known to reduce weed intensity. The higher plant population used and also complete covering of the soil earlier in intercropping system reduces weed infestation. In late maturing crops that are planted wide rows, presence of early maturing crops helps to cover the maturing crops that are planted wide rows, presence of early maturing crops helps to cover the vacant inters row space and keeps weed under check.
Quick growing non- competitive, compact legumes like green gram and black gram act as another crop due to their good canopy coverage.
In certain situations, intercrops are used as biological agents to control weeds, black gram , geen gram, cow pea in sorghum and cowpea in banana reduce weed population and one hand weeding can be avoided by this method, however, in some intercropping system like maize + groundnut, rice+ tapioca, maize + tapioca, weed problem is similar to their sole crops. The growth habit of genotype used in intercropping has a great influence on weed growth. Weed infestation in I/C is influenced by early growth and competitive additives of the component crops. If one or both the component crops are vigorous and cover the land area rapid ally, weed infestation is greatly reduced. Early crop canopy to cover the soil is more important than rapid increase in plant height.
It is well known that, different species of weeds are associated with different crops, but weeds present in sole crops are different than those present in intercropping system. At Hyderabad, in pearl millet as sole crop mixed weed flora was observed as Celosia, Digit aria and Cupreous in sole crop of groundnut. In pearl millet + groundnut intercropping system type of weeds changes with proportion of component crops. As more rows of groundnut are introduced in place of pearl millet of rows, there is a striking increase in both numbers and biomass of the tall and competitive Celosia, especially in groundnut rows.
Weed problem is less; weed control is necessary in intercropping system. But labour required for weeding is less; second weeding is not necessary because of crop coverage and limited weed growth. Normally two hand weeding are required, but it may restrict to one hand weeding under I/C. in sorghum + red gram or sorghum + cowpea, just one weeding is sufficient to get high yield as in weed- free check.
The critical period of weed free condition may be extended a little longer in I/C than in sole cropping. this is because the critical growth stages of the component crops very temporally in I/C. for example, critical weed free period has to be extended to first 7 weeks in sorghum + red gram I/C while sole sorghum crop requires only requires only 2- 4 weeks weed free period.
Chemical weed control is difficult in intercropping system because the herbicide may be selective to one crop but non- selective to another. Atrazine control weeds in sole sorghum, but it is not suitable for sorghum + red gram intercropping system, as it is toxic to red gram. Herbicides suitable for intercropping systems as-
* Maize + green gram & Maize + cowpea. Butachlor (pre- emergence) (Machete)
* Sorghum + pulse – fluchloriam (PPI) (Basalin) –or Alacholor (pre- emergence) (loss)
* Sorghum + red gram – prometryne (pre- emergence)
* Sugarcane + groundnut – nitro fen (pre-emergence) (to KE -25).
7. Pest and Disease in Intercropping System: Pest and diseases are believed to be less in intercropping system due to crop diversity than sole crops. Some plant combination may enhance soil fungicide and antibiotics through indirect effects on soil organic matter content. The spread of the diseases is altered by the presence of different crops. Little leaf of Brinjal is less when Brinjal is sheltered by maize or sorghum, as the insect- carrying virus first attacks maize or sorghum; virus infestation is less on Brinjal. Non – host plant in mixtures may emit chemicals or odor that affects the pests, thereby protecting host plants.
The concept of crop diversification for the management of nematode population has been applied mainly in the form of decoy and trap crops.
Decoy crops are non-host crops, which are planted to make nematode waste their infection potential. This is affected by activating larva of nematode in the absence of hosts by the decoy crops.
Trab crops are host crops sown to attract nematode but destined but destined to be harvest or destroyed before the nematode manage to hatch. This is advocated for cryst nematode. The technique involves sowing in pineapple plantations; tomatoes are planted and ploughed in to reduce root knot nematodes. There is also evidence that, some plants adversely affect nematode population through toxic action. Marigold reduces the population of pratylenchus species worms..