木霉拮抗菌的筛选与鉴定

Screening and Identification of the Antagonism Bacteria to Trichoderma

采用涂布平板法从植物和土壤中共分离得到301株细菌,其中从羊蹄甲、芦荟和香蕉皮等植物中分离到内生细菌86株,从土壤中分离到细菌215株。以食用菌栽培中的主要污染菌木霉,包括哈茨木霉(Trichoderma harzianum)、长枝木霉(Trichoderma longibrachiatum)等4种共8株木霉菌株以及蘑菇(Agaricus bisporus)、香菇(Lentinula edodes)等14种不同食用菌为实验菌,通过平板对峙培养法筛选出对木霉有拮抗作用而对食用菌拮抗性弱甚至无拮抗作用的细菌75株。采用传统分类法以及16S rDNA序列分析对其中作用效果最好的5株细菌进行了鉴定,结果显示,5株细菌均为枯草芽孢杆菌Bacillus subtilis。在实验中还发现,从羊蹄甲、芦荟和香蕉皮等植物中更容易分离到木霉拮抗菌。

301 bacteria strains were isolated from plant and soil by spreading plate method, and 86 strains of them were endophytic bacteria isolated from the Bauhinia, aloe vera and banana peel. 215 strains of them were isolated from soil. 8 strains of Trichoderma, which were main contaminatimg species to mushroom cultivation, and 14 different edible fungis were used as experimental material. 75 strains of 301 isolates were screened out by means of dual-culture tests, which were strongly antagonistic to Trichoderma spp., weak or not antagonistic to some mushrooms. The 5 strains with the strongest antagonism were identified as Bacillus subtilis according to traditional classification and 16S rDNA sequence analysis. We found that it is easily to isolate the antagonistic bacteria to Trichoderma from plant （i.e. the Bauhinia, aloe vera and banana peel） than soil.