Indian Phytopath. 66 (4) : 413-415 (2013) Effect of different formulations of entomopathogenic nematode Steinernema carpocapsae against root knot nematode Meloidogyne incognita on tomato A.K. MARU 1* , A.U. SIDDIQUI 2 , A. PARIHAR 2 , S.K. SHARMA 2 and A.S. SRIVASTVA 2 1 Department of Entomology, B.A.C., B.A.U., Sabour, Bhagalpur 183 210, Bihar, India 2 Department of Nematology, R.C.A., MPUAT, Udaipur 313 001, Rajasthan, India Key words: Entomopathogenic nematodes, formulation, Meloidogyne incognita, Steinernema carpocapsae, root knot nematode SHORT COMMUNICATION *Corresponding author: maruajay@gmail.com The entomopathogenic nematodes (EPNs) have been found effective against plant parasitic nematodes. Grewal et al. (2) used Steinernema carpocapsae and S. riobravis successfully against plant parasitic nematodes infesting turf grass. EPNs have been found compatible with nematicides in suppressing plant nematodes when used as a component in integrated nematode management (1). EPNs are effective for the management of root knot nematodes and S. glaseri suppressed penetration and reduction in egg production of Meloidogyne incognita in tomato roots (6). In view of the above facts, the present investigations were planned to evolve a newer and environmentally safer tactics for the management of root knot nematodes. Two year repetitive experimental trials were conducted to study the effect of different formulations of S. carpocapsae against M. incognita on tomato under micro plot at the Department of Nematology, RCA, Udaipur. Formulated infective juveniles (IJs) of S. carpocapsae were used as calcium gel alginate capsule (CGAC), water dispersible granules (WDG) and sponge bits at two different inoculum loads i.e. 10 4 and 2 × 10 4 number of IJs/pot. Carbofuran 3G @ 2 kg a.i./ha as associated check and control as untreated check were taken. Before the application of EPNs the initial nematode population (INP) of M. incognita in first year, 578 and second year, 592 larvae/200 cc soil were examined in micro plots and observations were recorded after 45 days on shoot length, shoot weight, root length, root weight, number of galls per plant, number of egg mass per plant, number of eggs and larvae per egg mass and nematode populations per 200 cc soil. The experimental results revealed maximum plant growth characters i.e. shoot length, shoot weight, root length and root weight and minimum nematode population parameters i.e. galls / plant, number of egg masses/ plant, eggs and larvae/ egg mass and nematode population/200 cc soil recorded with the application of sponge bit formulation @ 2 × 10 4 IJs/ pot followed by sponge bit formulation @ 10 4 IJs/pot as compared to other treatments (Table 1). Sponge bit formulation got comparatively better response in reduction of nematodes population than other formulations. All the treatments had a significant effect on the population, and multiplication of root knot nematode was low as compared to untreated control. Similar studies in this regards were conducted by Vyas et al . (10) who reported that the infective juvenile of S. riobravae provided a possible control of M. incognita on okra. Molina et al . (5) also studied the effect of live and dead infective juvenile of Heterorhabditis bacteriophora JPM4, H. baujardi LPP7, S. feltiae SN and S. carpocapsae against eggs and 2 nd stage juvenile of M. mayaguensis on tomato plant and found that the plant exhibited lower gall numbers as compared to control. Shapiro and Nyczepir (8) investigated the suppressive effects of S. feltiae against M. partityla on pecan and walnut and found up to 80% reduction in the populations of M. partityla. Different factors thought to be responsible for the suppressive effects of entomopathogenic nematodes on plant-parasitic nematodes. It might be due to the competition between the nematode groups for space in rhizosphere (9), attraction towards the CO 2 and other root exudates (7), increased density of predators due to the application of nematode biomass to the soil (3), behavioral response and increased natural enemies (2) and production of allelochemicals by the entomopathogenic nematode symbiotic bacteria complex (4).