Biological Control of Lettuce Sclerotinia Rot by Bacillus subtilis GG95

Hyun-Ju Lee1   Jin-Young Kim2   Jin-Gu Lee2   Soon-Sung Hong3   


Sclerotinia sclerotiorum, a plant pathogenic fungus, can cause serious yield and quality losses in the winter lettuce field. For biological control of S. sclerotiorum, soil-born microorganisms that inhibit the mycelia growth of S. sclerotiorum and Fusarium oxysporum were isolated from diseased soil. Among the isolates, bacterial isolate, GG95, which was identified as Bacillus subtilis according to the morphological, physiological characteristics and by 16S rRNA similarity, showed the highest level of inhi- bitory activity. The growth conditions for B. subtilis GG95 were optimized in TSB media (pH 7) by culturing at 28ºC for 24 hrs. Maltose or fructose and peptone were selected as the best carbon and nitrogen sources, respectively. Greenhouse experiment was performed to test effectiveness of B. subtilis GG95 in the control sclerotinia rot. Drench application (1 × 108 cfu/ml, 3 times) of the bacterial culture broth to lettuce showed an effectiveness value of 88%, suggesting that B. subtilis GG95 would be a promising biocontrol agent for control of sclerotinia rot.


본 연구는 농촌진흥청 기관고유 연구과제(PJ0099610120 14)에 의하여 수행된 연구결과입니다.

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