葡萄霜霉病拮抗细菌N6的分离、筛选及鉴定

Isolation, Screening and Identification of Antagonistic Bacteria Strain N6 Against Grape Downy Mildew

筛选葡萄霜霉病菌的拮抗菌株,为该病害的生物防治提供更多的资源。采用稀释平板分离法,从3个品种的健康葡萄叶片上分离得到细菌153株。初筛采用平板对峙法,得到5株拮抗辣椒疫病菌的菌株。采用叶盘法进行复筛,得到防治葡萄霜霉病效果好并且稳定的菌株N6,其防效达到74.2%。通过对菌株N6的形态、生长特性、生理生化反应、16S rDNA序列测定和系统发育分析,鉴定该菌株为砖红微杆菌(Microbacterium testaceum)。

The antagonistic bacteria against grape downy mildew were screened to provide more resources for biologically controlling of the disease. With streak plate method, 153 bacterial strains were isolated from the heahh grape leaves of three varieties. Screened by a dual culture technique, 5 strains exhibiting antagonistic activities against pepper phytophthora blight were obtained. Using the leaf disc for secondary screening, N6 was screened from the 5 strains. N6 had the better inhibitory effect, with biocontrol efficacy of 74.2%. The results showed the strain was identified as Microbacterium tes- taceum, through analyzing its morphological, physiological and biochemical characteristics, 16S rDNA sequence and phyloge- netics.