CONTROL OF PLANT-PARASITIC NEMATODES WITH ORGANIC AND INORGANIC AMENDMENTS IN AGRICULTURAL SOIL

The effects of different application rates of oilcakes of neem (Azadir achta indica) and castor (Ricinus communis), composted manure and urea on plant-parasitic, predatory and free-living nematodes and growth of pigeonpea (Cajanus cajan) in field trials were studied. Amendments to soil with these materials resulted in a significant decrease of plant -parasitic nematodes, whereas predatory and free-living nematodes incr eased. Neem and castor oilcakes were the most effective in reducing pl ant-parasitic nematodes. However, amendment to soil of composted manur e and urea was found to be beneficial in increasing free-living nemato des. As a consequence of suppression of plant-parasitic nematodes, pla nt growth parameters improved. Increasing doses of the amendments were found to be effective in further reducing plant-parasitic nematodes a nd increasing predatory and free-living nematodes.