木霉属2中国新记录种

Two new Chinese record species of the genus Trichoderma

【目的】明确我国南部地区土壤中分离得到的2株木霉菌的分类地位。【方法】采用PDAm培养基分离木霉菌菌株,通过形态学鉴定和内转录间隔区(ITS)序列、翻译延长因子1-alpha(Tef1-α)部分序列相似性分析对菌株进行初步鉴定;选取MEGA 4.0软件用Bootstrap最大简约法、水平3、重复1 000次来构建ITS、Tef1-α序列系统进化树并分析其亲缘关系。【结果】菌株CM01的ITS序列与GenBank基因库中Trichoderma intricatumstrain GJS 02-78 ITS序列同源性高达99%,在ITS序列系统进化树中与模式菌株T.intricatum GJS 02-78、Trichoderma atroviride DAOM 179514亲缘关系最近;其Tef1-α序列与GenBank基因库中Hypocrea intricate strain GJS 02-78 Tef1-α序列同源性高达99%,在Tef1-α序列系统进化树中与模式菌株H.intricata GJS 02-78亲缘关系最近;其形态描述和模式菌株一致。菌株SCGA5003的ITS序列与GenBank基因库中Trichoderma stromaticumstrain GJS 97-181 ITS序列同源性高达99%,在ITS序列系统进化树中与模式菌株T.stromaticum GJS 97-179、GJS 97-180、GJS 97-181、GJS 97-182、GJS 97-183亲缘关系最近;其Tef1-α序列与GenBank基因库中T.stromaticum strain GJS 97-183 Tef1-α序列同源性高达94%,在Tef1-α序列系统进化树中与模式菌株T.stromaticum CQSQ1032、GXNN7006亲缘关系最近;其形态描述和模式菌株一致。【结论】结合形态学特征与分子鉴定结果,判定菌株CM01为交织木霉(Trichoderma intricatum Samuels&Dodd/Hypocrea intricataSamuels et Dodd)、SCGA5003为子座木霉(Trichoderma stromaticum Samuels&Pardo-Schulth/Hypocrea stromatica Bezerra,Costa&Bastos),即发现木霉属2个中国新记录种。

[Objective] The objective of this study was to examine taxonomic position of two Tricboderma strains which were isolated from soil in southern China. [Methods] PDAm was used as a selective medium for isolating Triehoderma, then two strain was indetified by analysis of in- ternal transcribed spacer regions of the rRNA gene cluster （ITS）, partial sequences of transcription extensions factor 1-alpha （tefl-a） and observation of morphological characters. For phylogenetic analyses in MEGA 4.0, both ITS and tefl-a gene sequences were analyzed using the maximum parsimony approach of close-neighbor-interchange algorithm with search level 3, in which the ini- tial trees were obtained with the random addition of sequences （1 000 replicates）. [Results] The ITS gene sequences of the strain CM01 were naturally clustered with ITS gene sequences of Trichoderma intricatum strain GJS 02-78 in GenBank with 99% of homology, and had the closest phylogenetic relationship with T. intricatum GJS 02-78, Trichoderma atroviride DAOM 179514 in phylogenetic tree which based on ITS sequences of strains; the tefl-a gene sequence of the strain CM01 were naturally clustered with Hypocrea intricate strain GJS 02-78 are the closest phyloge- netic relatives with 99% of homology, and had the closest phylogenetic relationship with H. intri- cata GJS 02-78 in phylogenetic tree which based on tefl-a Sequences of strains; its morphological description accorded with type strain＇s. Meantime, the ITS gene sequences of the strain SCGA5003 were naturally clustered with ITS gene sequences of Trichoderma stromaticum strain GJS 97-181 in GenBank with 99% of homology, and had the closest phylogenetic relationship with T. stromaticum GJS 97-179, GJS 97-180, GJS 97-181, GJS 97-182, GJS 97-183 in phyloge- netic tree which based on ITS sequences of strains; the tefl-a gene sequence of the strain SCGA5003 were naturally clustered with T. stromaticum strain GJS 97-183 in GenBank with 94% of homology, and had closest relationship with T. stromaticum CQSQ1032, GXNNT006 in phy- logenetic tree which based on tefl-a sequences of strains; its morphological description were con- sistent with type strain＇s. [Conclusion] Utilizing a comprehensive approaches of morphological characters and molecular identification, we concluded that we found two new Chinese record spe- cies of the genus Trichoderma, strain CM01 was identified as Trichoderma intricatum Samuels ＆ Dodd/Hypocrea intricata Samuels et Dodd, strain SCGA5003 was identified as Trichoderma stromaticum Samuels ＆ Pado-Schulth/Hypocrea stromatica Bezerra, Costa ＆ Bastos.