Neem Genetic Diversity in India and its Use as Biopesticide and Biofertilizer*

Genetic variability in 12 neem growing states of India studied from 1999 to 2003 have been analysed in approximately 12150 elite samples for phenological and chemical traits. Seed weight varied from 9.1 to 33.1g and kernels 4.8 to 10.3g per 100 seeds. The total oil content in different states based on kernel weight ranged from 25.2 to 51.8%. Study established the positive and significant correlation between weight of seed and per cent oil contents in the seed (r= 0.6411*). Azadirachtin concentration in seeds varied from 0.19 to 0.92% with southern peninsula having comparatively higher azadirachtin as compared to other states. Neem seed pallets to be used as biofertilizer and biopesticides have been developed that contain 0.25 to 0.40% azadirachtin and are effective for the management of termites and white grubs. These pallets also provide nitrogen, P₂O, K₂O, crude protein. Phosphorus besides calcium, magnesium, iron, zinc, copper etc. and increase the fertility of the soil. The elite material so collected has been processed for pesticidal uses against pod borers, beet-army worm, weevils, whitefly, jassids, pulse beetles. Formulations proved toxic as well as growth inhibitor resulting larval-pupal intermediates, deformed larvae and pupae, pupal adult intermediates, deformed adults besides reducing the fecundity of the adults. Module for the use of neem in organic farming as organic manure and pesticide has been standardized in arid legumes, spice crop cumin and stored pulse seeds.