枯草芽胞杆菌HMB-20428与化学杀菌剂互作对葡萄霜霉病菌抑制作用和替代部分化学药剂减量用药应用

Inhibitory effects of Bacillus subtilis HMB-20428 interacted with chemical fungicides and decrement of chemical fungicides on oomycete pathogen Plasmopara viticola

为明确生防菌剂枯草芽胞杆菌Bacillus subtilis HMB-20428与化学杀菌剂互作对葡萄霜霉病菌Plasmopara viticola的抑制作用,采用生物测定与田间药效试验研究其最佳用药时期,筛选最佳生化互作组合,结合空间竞争能力和诱导抗病性生理测定试验了解互作增效机制,并建立葡萄霜霉病的综合防控技术。结果显示,枯草芽胞杆菌HMB-20428预防葡萄霜霉病最佳时期为发病前1个月,连续喷雾用药3～4次,间隔期10～15 d。研发出协同增效生化互作组合生防菌剂HMB-20428+嘧菌酯,及其与硅氧烷化合物增效组合,防效分别为91.06%～98.92%和87.78%～92.04%。枯草芽胞杆菌HMB-20428与嘧菌酯互作可增强枯草芽胞杆菌HMB-20428定殖能力和植株抗病作用,且定殖能力和抗病机制作用的增强时间基本一致。以生防菌剂HMB-20428替代部分化学药剂减量用药流程的防效为91.40%。表明枯草芽胞杆菌HMB-20428与嘧菌酯互作可达到减少化学药剂用量的目的。

To clarify the inhibitory effect of Bacillus subtilis HMB-20428 interacted with chemical fungicides on oomycete pathogen Plasmopara viticola,the optimal treatment period and the best biochemical interaction combination were investigated by bioassay and field efficacy trials;the synergisticy mechanism was studied by mesuring the space competition ability and induced resistance,and the integrated prevention and control system for grape downy mildew was established.The results showed that the best time for the prevention of grape downy mildew with B.subtilis HMB-20428 was one month before the disease occurrence.The times of continuous spraying times was three to four with the intervals of ten to 15 days.The new synergistic combinations of fungicide and biocontrol agent (B.subtilis HMB-20428+ azoxystrobin or plus 100%siloxane compounds)were found for controlling grape downy mildew,with a control effect of 91.06%-98.92% and 87.78%-92.04%,respectively.The space competition ability and resistance induced by B.subtilis HMB-20428 were increased when combined with azoxystrobin,with a basically synchronous enhancement effect.The effect of the integrated prevention and control system for grape downy mildew mainly based on biological agent reached 91.40%.The results indicated that the interaction between B.subtilis HMB-20428 and azoxystrobin could reduce the dosage of chemical fungicides.