解淀粉芽孢杆菌菌株P-r21抑菌广谱性及对番茄灰霉病的防治

为明确内生解淀粉芽孢杆菌(Bacillus amyloliquefaciens)菌株P-r21的抑菌广谱性及对番茄灰霉病的防治效果，本研究优化了菌株P-r21发酵条件，利用平板对峙法测定了该菌株对6种病原菌的抑菌活性及对番茄灰霉病菌(Botrytis cinerea)孢子萌发的抑制作用，并通过离体接种试验研究了对番茄灰霉病的防效。结果表明：菌株P-r21最佳发酵条件为在PYJ中培养初始pH 6.0，培养时间为12 h。菌株P-r21对供试的6种植物病原菌(Botrytis cinerea、Fusarium proliferatum、Rhizoctonia cerealis、Gaeumannomyces graminis、Fusarium graminearum、Colletotrichum karstii)的生长均表现出抑制作用；对C. karstii和B.cinerea抑制作用最强，抑菌率达到88.0%和84.5%。发酵滤液对B. cinerea孢子萌发抑制率达80.6%，对叶片和果实灰霉病的防效达到100%和80.0%；发酵液10倍稀释后防效也可达到67.1%和60.7%。本研究明...

Bacillus amyloliquefaciens P-r21: Broad-spectrum Antibacterial Effect and Control of Tomato Gray Mold

This experiment aims at clarifying the broad-spectrum antibacterial effect of endophytic Bacillus amyloliquefaciens strain P-r21, and determining its control effect on tomato gray mold. In this study, the fermentation conditions of strain P-r21 were optimized. The antibacterial activity of strain P-r21 against six pathogens and its inhibition on spore germination of Botrytis cinerea were determined by plate confrontation method, and its control effect on tomato gray mold was studied by in vitro inoculation test. The results showed that: the optimum fermentation media was PYJ, and the optimum condition was initial pH 6.0 and fermentation time of 12 h. Strain P-r21 exhibited antagonistic ability to six plant pathogens (Botrytis cinerea, Fusarium proliferatum, Rhizoctonia cerealis, Gaeumannomyces graminis, Fusarium graminearum, and Colletotrichum karstii). The inhibition effects of the strain on the growth of C. karstii and B. cinerea were the strongest, and the inhibition rates were 88.0% and 84.5%, respectively. The inhibition rate of B. cinerea spore germination treated with fermentation filtrate was 80.6%. The control effects on tomato gray mold disease of leaves and fruits treated with fermentation filtrate were 100% and 80.0%, respectively. The control effect of fermentation filtrate diluted 10 times could reach 67.1% and 60.7%, respectively. This study clarifies that strain P-r21 has broad-spectrum antibacterial effect and can be used for the control of tomato gray mold. The study lays a foundation for the application of this strain in the biological control of plant diseases.