Insecticidal spectrum of a novel isolate of Bacillus thuringiensis serovar japonensis

Abstract A newly isolated strain, designated Buibui, belonging to Bacillus thuringiensis serovar japonensis had potent larvicidal activity against the scarabaeids Anomala cuprea Hope and Popillia japonica Newman. Preliminary tests indicated that other scarabaeid larvae including A. albopilosa Hope, A. rufocuprea Motschulsky, A. daimiana Harold, A. schonfeldti Ohaus, Mimela splendens (Gyllenhal), and Blitopertha orientalis (Waterhouse) were equally susceptible to strain Buibui. However, the strain showed no insecticidal activity against larval lepidopteran insects including Bombyx mori (L.) (Bombycidae), Plutella xylostella (L.) (Plutellidae), Spodoptera litura Fabricius, S. exigua Hubner (Noctuidae), and Adoxophyes sp. (Tortricidae) and coleopterans, Allomyrina dichotoma L. (Scarabaeidae) and Henosepilachna vigintioctopunctata Fabricius (Coccinellidae). At 14 days post-treatment, the LC 50 and LC 95 of the δ-endotoxin against the cupreous chafer, A. cuprea , were estimated by probit analysis as 0.098 ± 0.019 and 0.29 ± 0.086 μg protein/g compost, respectively. Strain Buibui showed no β-exotoxin activity.