棉花立枯病拮抗真菌的筛选鉴定及防病作用研究

Screening, Identification and Biological Control of AntagonisticFungus Against Cotton Blight Caused by Rhizoctonia solani

为利用生防菌有效防控棉花立枯病,利用平板对峙法筛选对棉花立枯病菌具有高效拮抗作用的生防菌株,通过形态学和ITS序列分析方法对菌株进行鉴定,明确该菌株对棉花立枯病菌是否具有重寄生作用,并通过盆栽试验明确其对棉花立枯病的生防效果。结果表明,从24株木霉菌中筛选出1株对棉花立枯病菌具有高效抑制效果的菌株HBHD-1,抑制率可达89%,基于形态学和ITS序列分析方法对菌株进行鉴定,确定该菌株为棘孢木酶(Trichoderma asperellum),该菌株对立枯丝核菌可产生重寄生作用。盆栽试验结果表明,同时接种立枯病菌和棘孢木酶对棉花的生防效果可达70.85%。

In order to screen beneficial microorganisms for effectively controlling cotton blight,dual culture method was used to screening the highest biocontrol effect to the pathogen of cotton blight,the strain was identified based on the analysis of morphological traits and rDNA internal transcribed spacers(ITS),clarify whether this strain has a heavy parasitic effect on Rhizoctonia solani,and its biocontrol effect on cotton blight was clarified through pot experiments.The results showed that one strain HBHD-1 with high inhibitory effect on the pathogen of cotton blight was screened out from 24 strains of Trichoderma,with an inhibition rate of 89%.Based on morphological and ITS sequence analysis methods,the strain was identified as Trichoderma asperellum,which can produce heavy parasitic effects on Rhizoctonia solani.The results of the pot experiment showed that the biocontrol effect of inoculating Rhizoctonia solani and Trichoderma simultaneously on cotton could reach 70.85%.