一株拮抗烟草炭疽病的菌株ZYY-4的筛选、鉴定及生防活性测定

Screening,Identification and Biocontrol Activity of the Strain ZYY-4 against Tobacco Anthracnose

【目的】从秦岭太白山森林公园土壤中发掘出拮抗烟草炭疽病(Colletotrichum nicotianae Averna)的菌株,为防治烟草炭疽病提供生防资源.【方法】随机采集森林土壤,采用稀释涂布和划线分离纯化、平板对峙法和生长速率法筛选一株对烟草炭疽病有明显拮抗作用的菌株ZYY-4,并对ZYY-4进行生理生化分析和16S rDNA同源性分析,然后测定ZYY-4对烟草炭疽病的防治效果.[结果]在平板对峙实验中ZYY-4对烟草炭疽病菌的抑菌率达69.93%.经鉴定ZYY-4菌株为甲基营养型芽孢杆菌(Bacillus methylotrophicus).通过温室盆栽实验,ZYY-4液体发酵液在预防试验中对烟草炭疽病的防治效果达到77.83%,治疗实验中对烟草炭疽病的防治效果为62.77%.【结论】该菌株对烟草炭疽病具有高生物活性,有进一步用于绿色生防菌剂开发的潜力.

【Objective】The soil is a rich repository of microbial resources.In order to screen and extract the strains that antagonize tobacco anthracnose(Colletotrichum nicotianae Averna)from the soil samples of Qinling mountain forest,to provide biocontrol material for tobacco anthracnose control.【Method】In this study,Qinling deep forest soil was randomly collected,then spread plate method,streak plate method,and targeted screening of bacteria were performed.After that,physiological and biochemical analysis and 16SrDNA homology analysis of ZYY-4 were performed.【Result】Finding out the strain which had obvious antagonistic effect on tobacco anthracnose.The experiment results showed that the inhibition rate of ZYY-4 against tobacco anthracnose was 69.93%in the plate confrontation experiment.ZYY-4 strain was identified as Bacillus methylotrophicus.Through the greenhouse pot experiment,the control effect of the ZYY-4 liquid fermentation on tobacco anthracnose in the prevention test was 77.83%,and the control effect on tobacco anthracnose in the treatment test was 62.77%.【Conclusion】The ZYY-4 strain has highly biological activity against tabacoo anthracnose and has potentiality for further development in green biocontrol agents.