Effects of four soil-originated Bacillus spp. on the great spruce bark beetle, Dendroctonus micans (Kugelann) (Coleoptera: Curculionidae, Scolytinae)

Abstract

Fifty bacterial cultures were isolated from 156 soil samples. In order to identify six bacteria in both systems, a fatty acid methyl ester (FAMEs) analysis was conducted, and carbon utilization profiles were assessed, using microbial identification, Biolog Microplac Systems, and the VITEK bacterial identification systems (bioMerieux, Prod. No. 21341 and 21342). Results showed that four species of Bacillus ssp., isolated from soil, were safe and efficient biological control agent for plant pests in Ordu, Turkey. These bacteria were Bacillus mycoides, B. cereus, B. thuringiensis, Paenibacillus validus, B. atrophaeus, and Arthrobacter globiformis. Laboratory tests were conducted to assess the potential of the isolates against the great spruce bark beetle, Dendroctonus micans (Kugelann) (Coleoptera: Curculionidae, Scolytinae) (Curculionidae, Scolytinae). Mortality rates of larvae and adults were 60 and 50%, 40 and 30%, and 80 and 70% when using B. mycoides, B. cereus, and B. thuringiensis, respectively. P. validus, B. atrophaeus, and A. globiformis showed insufficient rates of mortality, 30 and 20% on the larvae and adults of D. micans, respectively. Also, these isolates had no antimicrobial effect on pathogen microorganisms. They have, however, a lethal effect on some insect groups that are agriculture and forest pests. The results indicated that the Bacillus isolates in question can be used as one of the biological control agent.