Efficacy of antagonistic bacteria for biological control of browning disease on button mushroom
Mushroom is cultivated as one of the major economical crops in many areas in Korea. The total production has steadily increased from approximately 186,400 M/T in 2007 to 190,111 M/T in 2011. The button mushroom, Agaricus bisporus, showed the 5th production to 13,052 M/T in 2011. Several bacteria are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Pseudomonas agarici is the causal agent of browning disease of commercial mushrooms. In this study, antagonistic bacteria to P. agarici were selected in vitro tests using confrontation bioassay and paper disk diffusion assay. The most active bacteria, HC12 were selected and their control efficacy of brown blotch disease was investigated in this study. After proceeding antagonistic test, HC12 was selected as a strong antagonist against P. agarici and the HC12 strain was identified as Alcaligenes sp. with the cultural, physiological and biochemical properties and analysis of the 16S rRNA. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 0.5% dextrin, 1.5% yest extract, 1% NaNO3, 0.5% KH2PO4, and 1.5% L-asparagin at pH 9.0 at 30℃. Control efficacy of browning disease by HC12 treatment was 63% on Agaricus bisporus..