Virulence Experiments of Two Strains of Nomuraea rileyi on Larvae of Spodoptera litura Fabricius

Two strains of Nomuraea rileyi, separated from Spodoptera depravata (F889) and Anticarsia gemmatalis (F815) in Japan, were inoculated into the larvae of Spodoptera litura. During the days from infection to host death, larvae were reared with artificial diet. Five concentrations of conidia suspension were made for the experiments. These were 10⁷, 10⁶, 10⁵, 10⁴, 10³ conidia·mL^-1. The results showed:LC50 were 5.38 (F889) and 5.71 (F815). The mortalities, when concentration was 1×107 conidia·mL^-1, were 89.5% (F889) and 84.2 (F815).