Influence of Dosage of Steinernema carpocapsae (Weitser) S. glaseri Steiner and Heterorbabditis indicus (Poinar, Karuuakar and David) on Mortality of the Host and Multiplication of Infective Juveniles in Sugarcane Internode Borer,

Steinernema carpocapsae (Welser), S. glaseri (Steiner) and Heterorhabditis indicus (Polnar, Karunakar and David) at an Inoculum level of 40 infective juveniles (IJ) per Illrva caused 97.5 - 100 per cent mortality of Chilo Sacchariphagus indicus (Kapur) larvae and the morfality decreased with decrease in dosage levels. There was no significant difference in the mortality caused by the three species of nematodes. The multiplilcation of infective juveniles (IJ) per unit body weight of the host was higher in H. indicus than in S. capcapsae and S. glaseri. The dosage level of 20 IJ/larva yielded significantly high nematode multiplication in S. glaseri (37,335.8 IJ/larva) and H. indicus (2,10,283.3 IJ/larva) while S. carpocapsae multiplied to the maximum at a dosage of 10 IJ/larva (1,35,894.3 IJ).