Grain/Seed Protectants against Callosobruchus chinensis (L.) on Soybean, Glycine max (L.) Merrill under Storage Condition

Efficacy of plant oils, botanical leaf powders as well as synthetic insecticides as grain protectants against Callosobruchus chinensis Linnaeus on stored soybean is reported. Soybean seed treated with neem, castor and pongam oil @ 1 per cent (v/w) recorded significantly higher adult mortality (≥ 55%) of C. chinensis during storage period of 6 months with higher half-life (about 2.5 months), higher gross persistency (4492.43 to 3445.88), lower population growth (3.11 to 6.15 adult emergence) and lower per cent loss in germination (15.96 to 20.94%). Among the various leaf powders, neem, eucalyptus and pongam @ 2 per cent recorded 38 per cent adult mortality, higher half-life (more than 3 months) and gross persistence (> 3180) values, lower number of adult emergence (≤ 1.82) and loss in germination (≤ 17%) and were found to be more effective treatments. Among the insecticides; deltamethrin 2.8 EC, cypermethrin 10 EC, spinosad 45 SC and fenvalerate 20 EC @ 4 ppm emulsion/suspension were found to be more effective against C. chinensis and recorded significantly higher mortality (> 70%) with higher half-life values (8 to 6 months), higher persistency (5933 to 4982) and lower number of adult emergence (≤ 2.64). These insecticides did not affect the germination of soybean.