Antifungal activity of Bacillus sp. AM-651 against Phytophthora capsici = 고추역병 유발병원균 Phytophthora capsici에 대한 Bacillus sp. AM-651의 항진균활성

Abstract

Biological antagonists of Phytophthora capsici were isolated from soil in Gyeongbuk, Korea. Among the isolated bacteria, a Bacillus sp. was identified from 16S rDNA sequence analysis and named Bacillus sp. AM-651. Bacillus sp. AM-651 strain which can strongly a antifungal activity against Phytophthora capsici. Culture conditions for the maximum production of the antagonistic substance were optimized. The production of antibiotic were high on modified Davis mineral medium pH 7 at 30oC. The medium for highest production of the agonistic substance optimized. It is composed the best activity on glucose, (NH4)2SO4 and K2HPO4 at 0.5%, 0.1%, and 0.7%, respectively. By time course of culture solution selected Bacillus sp. AM-651, the culture solution after 48hrs had strongly growth inhibition rate against P. capsici. And culture solution of Bacillus sp. AM-651 was stable within a pH range 5~11 and temperature range 4~70oC. Bacillus sp. AM-651 cultured broth shown fungal growth inhibitory activitiy against B. sorokiniana, B. cinerea, R. solani avove and beyond P. capsici and comparatively showed a high activity against C. gloeosporioides, B. dothidea, B. cinerea and F. graminearum by agar diffusion method.