Principle of Crop Rotation Crop Rotation It is defined as the growing of crops in an orderly and well planned way. It depends upon  Type of crop sown  Local economic factor  Traditioning Objective of crop rotation 1. To prevent the built up of insect pest, weeds and soil born diseases 2. To maintain soil fertility for the next crop 3. To conserve soil erosion which may cause from wind or water 4. To conserve soil moisture from one season for the next 5. To ensure a balanced programme of work throughout the season Principle of crop Rotation The traditional principles on which the planning of crop rotations is based are following which are helpful for the best crop rotation  Alternating growing of crops with differential ability to absorb nutrients from the soil or having different root depth  A planned succession of crops that take it to account any detrimental or beneficial effects of one crop on the following crop. These affects may be due to toxic organic matter, soil structure, soil microorganisms or residual soil moisture 1. Alternating crops susceptible to certain diseases with those that are resistant ( alternate host provision) 2. Alternating soil exhausting crops with crops that contribute to the improvement of soil fertility 3. Alternating crops with different peak requirements of labor and water etc. The traditional crops rotation is in general exhausting and makes no contributions to soil fertility. The basic problem is therefore to device a crop rotation that will raise the level of soil fertility thus making it possible for the following crop to benefit fully from the favorable moisture require prevailing during its growing periods. It is frequently assumed that pulses are desirable proceeding crops for the winter cereals and it was originally that increasing the area under pulses would have beneficial effects on soil fertility. However results are always disappointing at harvesting. A seed crop from the legume usually result in a drop of at least 30% in the yield of the following wheat crop as compared with following wheat with fallow Legume (seed) ______ Wheat (30%loss) Wheat ____________ Fallow ________ Wheat Leguminous crops that are not allowed to mature seed but are used for green manure, hay, silage, have been shown to improving the soil fertility. When a deep rooted legume crop such a lucern is turned under for green manure, the soil has usually dried out to a depth of several feet when the legume is cut before seed I formed the amount of plant