甜叶菊斑枯病生物防治拮抗菌株的筛选

从甜叶菊根部土壤中分离到放线菌A01和A64菌株,生长繁殖速度快,抗污染能力强,抑菌效果好,为高效拮抗菌株.2个拮抗菌株的拮抗活性能稳定遗传.初步鉴定两菌株为链霉菌属(Streptomyces Waksman and Henrici),A01为黄色类群的1个种,A64为蓝色类群的1个种,种名未定.喷施抗生菌剂,可有效降低斑枯病病情指数,平均防效为56.3%.A01和A64混合构成的抗生菌剂防治效果明显好于两个菌剂单用,差异达到显著水平.抗生菌剂可显著提高甜叶菊叶片产量.平均增产18.7%.尤其在连作小区,增产效果更为明显.

Isolating of actinomyce strains on iocontrol of stevia leaf spot disease

Strains A01 and A64 are two actinomyces isolated from stevia rhizosphere which showed a high growth rate and strong antibiosis activity and these 2 strains kept their high growth rate and stable antibiosis activity.Taxonomy identification suggested that these two isolates are members of Streptomyces Waksman and Henrici.A01 belongs to yellow group, and A64 is an isolate of blue group.Application of biocontrol agents on stevia leaves could effectively suppress the leaf spot disease.The average control effect was 56.3%.Mixture of A01 and A64 showed a significantly enhanced biocontrol effect compared with the individual isolates.The average yield increasing was 18.7%, especially in the mono-cropping area, yield increasing was more distinct.