马铃薯黑痣病菌拮抗细菌的筛选及鉴定

Screening and Identification of Antagonistic Bacteria against Potato Black Scurf

为分离筛选出对马铃薯黑痣病菌有较强拮抗作用的生防菌,采用平板对峙筛选拮抗细菌,盆栽试验测定其防治效果,通过形态特征、生理生化特性及16S rRNA基因序列鉴定生防细菌。结果表明,通过筛选获得1株有明显拮抗效果的细菌KSD17,菌株平板对病菌抑菌率高达78.91%。该菌株具有产纤维素酶、蛋白酶、β-1,3-葡聚糖酶能力,盆栽防效为66.17%,且对马铃薯植株株高和匍匐茎数均有提高,分别增加了9.05%和22.0%。菌落呈不透明乳白色,无皱褶,粘稠,无色素产生,边缘不规则,结合16S rRNA基因序列和生理生化分析,将其鉴定为多粘类芽孢杆菌。拮抗菌株KSD17是具有较强生防潜能的菌株,对防治马铃薯黑痣病生物菌剂的开发具有良好的前景。

In order to isolate and screen out the bacterial strains with strong antagonistic effect on potato black scurf,the antagonistic bacteria were screened by plate confrontation,the control effect was determined by pot experiment,and the biocontrol bacteria were identified by morphological characteristics,physiological and biochemical characteristics and 16S rRNA gene sequence.A bacterial strain KSD17 with obvious antagonistic effect was obtained by screening,and the bacteriostatic rate of the strain plate was as high as 78.91%.The strain had the ability to produce cellulase,protease,β-1,3-glucanase,the pot control effect was 66.17%,and the plant height and stolon number of potato plants were increased by 9.05%and 22.0%.The colonies were opaque and milky white,without wrinkles,viscous,without pigment production,and with irregular edges.Combined with 16S rRNA gene sequence and physiological and biochemical analysis,it was identified as Paenibacillus polymyxa.The antagonistic strain KSD17 was a strain with strong biocontrol potential,and had a good prospect for the development of biological agents for the prevention and treatment of potato black scurf.