Green gram is most important legume crop and richest source of 24% easily digestible protein. The green gram is attacked by number of insect pests but Spodoptera litura is more serious pest. The uses of entomopathogenic nematodes (EPN) as a biological control agent of insect pests are more effective. EPNs have been found effective for the management of tobacco caterpillar and are used as bio insecticides against a number of lepidopteran pests. The mass multiplication of Steinernema carpocapsae can be done on rice moth (Corcyra cephalonica), greater wax moth (Galleria mellonella), gram pod borer (Helicoverpa armigera) and tobacco caterpillar (Spodoptera litura). Infectivity of entomopathogenic nematode, S. carpocapsae against tobacco caterpillar was studied and observation was recorded after every day up to 10 days with different inoculum levels viz., 10,000, 15,000 and 20,000 IJs/plant of S. carpocapsae. The experimental results revealed that maximum 82.50% mortality of S. litura was observed at inoculum level 20,000 IJs/ plant of S. carpocapsae after 9th day of inoculation followed by 75.00% mortality at inoculum level 15,000 IJs/plant. While, minimum 67.50% mortality was recorded at inoculum level 10,000 IJs/plant. Therefore, it was concluded that the mortality of insect larvae increased with an increase in the inoculum levels and period of exposure.

Population fluctuations of root-knot nematode, Meloidogyne incognita during crop season were studied on cucumber in two poly-houses of different locations. For the observations plant and soil samples were taken at fifteen days intervals throughout the crop season up to 120 days. Results showed that lowest 2.60 and highest 74.00 galls/5g roots of cucumber found at 15 and 120 days after sowing. No egg masses observed just 15 days after sowing of crops due to root-knot nematode complete their entire life cycle within 25 to 30 days. While, maximum 63.70 egg masses/5 g roots produced 120 days after sowing. The maximum 317.40 and minimum 264.20 eggs and larvae per egg mass was observed at 30 and 120 days after sowing in cucumber It was observed that egg mass contain found maximum when the population level is lowest and the egg mass contained reduced with increasing in the population of root-knot nematodes. Results also showed that minimum 1347.90 and maximum 2256.90 juveniles per 100 cc soil was found at 15 and 120 days after sowing of cucumber in poly-house.

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Root-knot nematode, Meloidogyne incognita infects tomato crop (Alam et al., 1975;Khan et al., 1978) and causing major economic damage to agricultural vegetable production including tomato around the world (Sasser,

Okra [Abelmoschus esculentus (L.) Moench.] is an important vegetable crop grown in tropical and subtropical regions of the world. The production of okra suffers from number of pest and pathogens including nematodes. Amongst nematodes, root-knot nematode, Meloidogyne incognita is most important and responsible to cause significant economic losses in worldwide due to favorable soil and environmental conditions. In present investigation neem, karanj and mustard oil-cakes have been tested for the management of root-knot nematode, M. incognita infecting okra on farmer"s field naturally infested with test nematode. These were applied @ 2, 4 and 6 q/ha maintaining chemical treated (carbofuran 2 kg a.i./ha) and untreated control for comparing the experimental results. The observations on number of galls/plant, egg masses/plant, eggs and larvae/egg mass, final nematode population/100 cc soil and yield were recorded. Results showed that neem cake @ 6 q/ha was proved to be most effective for the management of M. incognita on okra while karanj cake @ 6 q/ha was found best to enhanced crop yield (49.18-53.51 %) followed by neem cake @ 6 q/ha (40.98-45.61%) and karanj cake @ 4 q/ha (39.34-43.86 %) over untreated control. Higher yield was obtained with the application of karnaj cake @ 6 q/ha as compared to carbofuran @ 2 kg a.i./ha during both the years.