生防细菌CNY-04筛选、鉴定及其对灰霉病菌的防效

Screening and identification of biocontrol strain Serratia grimesii CNY-04 against Botrytis cinerea

摘要:

【目的】为研究土壤细菌对蔬菜灰霉病的生防价值, 从辽宁、山东等地区的蔬菜种植基地采集土壤样本56份, 分离、筛选出对灰霉病具有稳定拮抗作用的细菌9株。【方法】采用平板对峙培养法进行初筛、复筛, 用抑菌圈法测定其抑菌效果, 并进行离体果实试验验证其对蔬菜灰霉病的防治效果, 通过形态学特征、生理生化特征及16S rRNA基因序列分析研究其分类地位。【结果】细菌CNY-04对蔬菜灰霉病的拮抗能力最强且遗传稳定, 抑菌圈直径达到34 mm; 初步鉴定该菌株为格氏沙雷菌(Serratia grimesii), 尚未见该菌在生防上的报道; CNY-04液体菌剂对离体番茄果实灰霉病的防效为69.23%, 50%多菌灵防效为75.39%, 24 h时接种CNY-04处理的番茄发病率为40.0%, 而48 h时接种处理的发病率为51.1%。【结论】CNY-04是一株较为理想的拮抗菌, 丰富了生防资源。

Abstract:

[Objective] In order to study the effect of soil bacteria against vegetable Botrytis cinerea, we isolated 9 strains from 56 samples obtained from greenhouses in Liaoning and Shandong Province in China. [Methods] The plate-confrontation method and antibacterial circle method were used for preliminary screening and antimicrobial testing in vitro, respectively. The effect of strain CNY-04 against vegetable Botrytis cinerea was measured in detached condition. The taxonomic identification of strain CNY-04 was studied by analyzing its morphology characteristics, physiological and biochemical characteristics, and 16S rRNA gene sequence. [Results] Strain CNY-04 exhibited genetic stability and strong antagonistic ability on vegetable Botrytis cinerea. From the taxonomic identification result, this bacterium was identified as Serratia grimesii. Strain CNY-04 inhibited Botrytis cinerea on tomato by 69.23%, close to that of 75.39% by carbendazim 50 WP. The incidences of Botrytis cinerea in groups inoculated with strain CNY-04 were 40.0% at 24 h and 51.1% at 48 h. [Conclusion] Strain CNY-04 is a potential biological control agent for vegetable Botrytis cinerea.