Pathogenicity of epn to certain foliar insect pests

Pathogenicity of Heterorhabditis indica and Steinernema glaseri was studied to four important foliar insect pests viz., Helicoverpa armigera, Spodoptera litura, Plutella xylostella and Cnaphalocrosis medinalis. Both H. indica and S. glaseri were found to be pathogenic to all the insects tested. LC50 value of H. indica were 2.01, 5.46, 7.32 and 9.40 infective juveniles (I J)/larva for P. xylostella, C. medinalis, S. litura and H. armigera, respectively. For pupal stage, LC50 were 73.29, 86.28, 104.45 and 120.79 I J/pupa for S. litura, P. xylostella, H. armigera and C. medinalis, respectively. LT50 values followed the same trend. LC50 values of S. glaseri were 2.53, 5.17, 9.04 and 10.51 I J/larva for P. xylostella C. medinalis, S. litura and H. armigera, respectively. LT50 values were 23.60, 58.54, 44.52 and 47.54 hrs. for P. xylostella, C. medinalis, S. litura and H. armigera, respectively. LC50 and LT50 values for pupal stage were 95.29, 161.67, 108.12 and 122.73 I J/pupa and 68.23, 100.02, 69.91 and 77.21 hrs. for P. xylostella, C. medinalis S. litura and H. armigera respectively. LC50 and LT50 values of both H. indica and S. glaseri for larva and pupa were significantly different from each other for all the four insects tested.