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.