具有除草活性的海洋放线菌筛选与鉴定

Screening and Identification of Marine Actinomycetes with Herbicidal Activity

以小麦为初筛靶标生物,筛选到3株对其生长具有抑制作用的海洋放线菌。采用平皿法以反枝苋、生菜和黄瓜为供试植物,测定3株海洋放线菌的除草活性。结果表明,菌株SLR2、GC3、AF2发酵液的上清液对反枝苋、生菜和黄瓜的种子幼根和幼芽具有较强的抑制作用,其中3种菌株发酵液的上清液对反枝苋幼根和幼芽的抑制率为100%,5倍稀释液对反枝苋的抑制率均在50%以上;SLR2、GC3发酵液的上清液对生菜生长的抑制率为95.1%~100%和80.9%~100%;SLR2发酵液的上清液对黄瓜生长的抑制率为73.8%~77.4%。根据形态特征和16S r DNA序列分析,将SLR2、GC3和AF2鉴定为原小单孢菌Promicromonospora umidemergens、浅多色链霉菌Streptomyces pluricolorescens和小链霉菌Streptomyces parvus。

Three marine actinomyces with inhibitory effect on the growth of wheat were screened. The herbicidal activity of the three strains were determined using the plate method and with Amaranthus retroflexus,Lactuca sativa and Cucumis sativus as the tested plants. The results showed that there were obvious inhibitory effects of SLR2,GC3 and AF2 fermentation supernatant fractions on young root and bud growth of A. retroflexus,L. sativa and C. sativus. The inhibition rates of SLR2,GC3 and AF2 fermentation supernatants on young roots and buds of A. retroflexus were all 100%,and those of their five times supernatant diluents were more than 50%. The inhibition rates of SLR2 and GC3 fermentation supernatants on L. sativa were 95. 1% ~ 100%and 80. 9% ~ 100%,respectively,and those of SLR2 fermentation supernatants on C. sativus were 73. 8% ~77. 4%. Based on the 16 S r DNA sequence and physiological properties,the strain SLR2,GC3 and AF2 were identified as Promicromonospora umidemergens, Streptomyces pluricolorescens and Streptomyces parvus respectively.