一株盖姆斯木霉TW20050的鉴定及功能评价

The Identification and Functional Assessment of Trichoderma gamsii Strain TW20050

明确木霉菌株TW20050的分类地位,并评价其生物学功能。通过形态学特征结合ITS、tef1及rpb2序列分析进行种类鉴定,利用菌丝生长速率法测定菌株的抑菌能力,利用透明圈大小定性检测菌株的水解酶活性。结果表明:菌株TW20050的形态学特征与Trichoderma gamsii一致,其ITS、tef1和rpb2序列与Trichoderma gamsii的同源性均达到99%以上,在以rpb2构建的系统发育进化树中,TW20050与Trichoderma gamsii strain S488[KJ665270.1]位于同一分支。菌株TW20050在PDA平板上对10种植物病原真菌均有抑制作用,对终极腐霉的抑制率最高,达92.0%。菌株TW20050具有蛋白酶、几丁质酶、β-1,3-葡聚糖酶及纤维素酶活性,其中蛋白酶活性和纤维素酶活性较高,透明圈宽度分别为9.8 mm和6.5 mm。综合形态学特征和序列分析,将菌株TW20050鉴定为盖姆斯木霉。菌株TW20050不但对植物病原真菌具有广谱抗性,而且具有多种水解酶活性,是一株较有潜力的生物防治菌株。

This study was to examine the taxonomic position of strain TW20050,and evaluated its biological function. The strain was identified by analysis of internal transcribed spacer regions of the rRNA gene cluster（ ITS）,partial sequence of transcription extensions factor 1-alpha（ tef1） and the second largest subunit of RNA polymerase II（ rpb2）,the morphological characters were also observed. The antifungal activity were determined by mycelial growth rate method,and hydrolase activity was determined by hydrolyzation radius. The ITS,tef1 and rpb2 sequences of strain TW20050 were no less than 99% homology with Trichoderma gamsii. Strain TW20050 and Trichoderma gamsii strain S488 [KJ665270. 1] were belong to same one branch in phylogenetic tree based on rpb2 gene sequences,the morphological description were consistent with Trichoderma gamsii. Strain TW20050 had antifungal activity against 10 plant pathogenic fungi types,and the inhibition ratio was 92. 0% against Pythium ultimum. Strain TW20050 had proteinase,chitinase,β-1,3-glucanase and cellulase activity,the hydrolyzation radius of proteinase and cellulase activity were 9. 8 mm and 6. 5 mm,respectively. Utilizing a comprehensive approaches of morphological characters and molecular identification,we identified strain TW20050 as Trichoderma gamsii.Strain TW20050 had broad-spectrum antifungal activity and various hydrolase activity,it was a potential biological control agent.