H.M. HASSAN AND A.A. ABD-EL ALIM
Plant Protection Dept., Fac. of Agric., Minia Univ.

ABSTRACT

Last instar larvae and newly formed pupae of Sesamia cretica Led. and Chilo agamemnon Bles. were exposed to Steinernema carpocapsae (All strain) and Heterorhabditis bacteriophora (NC strain). Larvae and pupae of C. agamemnon were susceptible to S. carpocapsae than H. bacteriophora. In contrast, S. cretica showed susceptibility to H. bacteriophora than S. carpocapsae. It is obvious that larval stage was more susceptible to infection than pupal stage. On the other hand, production of dauer larvae indicated the infectivity of nema todes which differ according to the host and the nematode species, whereas the production of S. carpocapsae from S. cretica was massive than H. bacteriophora. However, the emergence of H. bacteriophora was greater than S. carpocapsae from C. agamemnon larvae. It is obvious also that the production of nematodes from S. cretica in general was higher than from C. agamemnon. Histological examination of the infected larvae of S. cretica indicated reduction in contents of fat bodies, deterioration of muscles and body epithelial cells.

Key Words: Sugarcane borers, Entomogenous nematode, Sesamia cretica.