拮抗细菌发酵提取物与井冈霉素混配对水稻纹枯病的毒力研究

Toxicity of Antagonistic Bacterium Fermentation Extracts and Validamycin against Rhizoctonia solani

利用菌丝生长速率法分别测定了拮抗细菌SU8发酵提取物、井冈霉素及其5种不同质量比的混配剂对水稻纹枯病菌的抑制效果,并进行盆栽防病试验。结果表明,SU8发酵提取物抑制水稻纹枯病菌的EC50为4 120.17 mg/L,60%井冈霉素可溶性粉剂的EC50是404.8 mg/L;当两者分别以质量比9︰1、4︰1、1︰1和1︰9进行混配时,增效系数分别达到了7.53、3.68、3.31和1.81,均表现出明显的增效作用;当两者以质量比1︰4进行混配时,增效系数为1.01,表现为协同作用;两者质量比9︰1和4︰1的混配剂在盆载试验中防病效果高于单一的井冈霉素。这表明,与SU8发酵提取物混配,能显著增强井冈霉素对水稻纹枯病的防治效果。

This study was conducted with the mycelium growth rate method to respectively determine the inhibition effects of SU8 fermentation broth extract, validamycin or their mixtures at fi ve different mass ratios on Rhizoctonia solani in room and pot experiments. The results showed that the EC50 of the extract against Rhizoctonia solani was 4 120.17 mg/L and that of 60% validamycin soluble powder was 404.8 mg/L; the synergistic coeffi cients reached 7.53, 3.68, 3.31 and 1.81 when the extract and validamycin were mixed at the mass ratios of 9：1, 4：1, 1：1 and 1：9, showing signifi cant synergistic effects, respectively; the synergistic coeffi cient reached 1.01 when the extract and validamycin were mixed at the mass ratio of 1：4, showing synergy effect; and the control effi cacy of the mixture at the mass ratios of 9：1 and 4：1 in the pot experiments higher than that of single validamycin. So the SU8 fermentation broth extract could enhance validamycin effi cacy on Rhizoctonia solani control.