枯草芽孢杆菌(Bacillus subtilis) B-912对采后柑桔果实青、绿霉病的抑制效果

 用从土壤中分离到的枯草芽孢杆菌B-912作为生防拮抗菌,主要研究在不同贮藏温度下不同接种时间的B-912活菌液、热处理液和过滤液对柑桔青、绿霉病的抑制效果。B-912活菌液的抑菌效果最佳,热处理液和过滤液次之,但均显著地好于对照。较高的贮藏温度有利于拮抗菌对病菌的抑制作用,活菌液处理的果实在25℃下的发病率及病斑直径均小于15℃下的果实,24h后接种病菌孢子的果实其发病率及病斑直径一般都高于48h后接种的果实。实验证明,枯草芽孢杆菌的抑菌机理主要是产生抗菌素。

POSTHARVEST BIOLOGICAL CONTROL OF GREEN MOLD AND BLUE MOLD OF CITRUS FRUITS BY Bacillus subtilis

Bacillus subtilis strain B-912, isolated from the soil of apple orchard, was used as an antagonist for postharvest biological control of green mold (Penicillium digitatum) and bluemold (Penicillium italicum) on citrus fruit. In vitro test showed that B-912 was more effective against green mold than blue mold. The cell culture of B-912 provided better control of green mold and blue mold than heat treated culture and cell free filtrate. All treatments significantly inhibited the diseases both in vitro and in vivo compared with control. Fruits treated with cell culture and stored at 25℃ had lower infection rate and smaller lesion diameter than those stored at 15℃. There were higher disease incidence and larger lesion diameter in fruits inoculated with spores 24 h after B-912 than 48 h after B-912. The mechanism of B-912 activity appeared to involve production of an antifungal substance.