树莓炭疽病病原菌鉴定

Identification of the pathogen causing anthracnose of raspberry

【目的】为了明确引起树莓炭疽病的病原,【方法】从30份标样中采用组织分离法分离得到了18个代表性菌株,并随机选取一个菌株LN-14,对该菌株的形态学特征、菌落特性以及病菌的致病性进行了研究。采用真菌rDNA-ITS区域通用引物ITS1和ITS4对菌株进行PCR扩增,运用DNAMAN软件构建该菌株与其他近缘种类菌株的系统发育树。【结果】该菌在PDA培养基上菌落呈灰白色,产生黑色分生孢子盘,分生孢子无色、单孢子呈椭圆形12～19μm×4～5μm。PCR扩增得到534 bp的特异性片段,测序、比对结果显示该菌与Colletotrichum gloeosporioides[HQ264183]、C.gloeosporioides[HQ264182]的相似性高达100%,与引起杧果炭疽病的C.gloeosporioides[JX560098]亲缘关系较近聚类为同一个分支,而与草莓炭疽病菌C.fragariae[JN943084]亲缘关系较远。【结论】形态学和分子鉴定表明辽宁地区树莓炭疽病的病原菌为胶孢炭疽菌(Colletotrichum gloeosporioides)。

[Objective]The objective of the study was to identify the pathogen of Raspberry anthracnose in Liaoning province. [Method ] 18 anthracnose strains were isolated from 30 samples by tissue isolation techniques . One strain LN-14 randomly selected was studied on the level of the characteristics of mor- phology,pathogenicity and sequence analysis of the internal DNA. A specific fragment was amplifid using fungus universal transcribed spacer region of the ribosomal primers ITS1 and ITS4 by the PCR methord. Phylogenetic tree was constructed using DNAMAN software. [Result]The results showed that the pathogen on the medium of PDA formed grey colonies, black acervuli, colorless and elliptic conidium with the size of 12-19 p^mx4~5 ~xm .A specific 534 bp fragment was amplified ,and the results of sequencing and comparison on GenBank indicated that the homology of LN-14, Colletotrichum gloeosporioides [HQ264183] and C. gloeosporioides[HQ264182] reached 100%.The cluster analysis showed that the strain LN-14 had closer genetic relationship with C. gloeosporioides [JX560098] causing mango anthracnose, and they could be clustered in the same branch. On the contrast, LN-14 had distant relationship with C. fragariae[JN943084].[Conclusion]Morphological and molecular identification suggested that the patheogen C. gloeosporioides was confirmed to be responsible for Raspberry anthracnose in Liaoning Province.