向日葵链格孢的分类研究

Taxonomic study of Alternaria helianthi

引起油葵黑斑病的病原菌在我国一直采用向日葵链格孢Alternaria helianthi这个学名。然而国际上已更名为向日葵拟链格孢Alternariaster helianthi。2017年从陕西省华阴市采集到油葵黑斑病样品。通过单孢分离获得6株病原菌菌株,致病性检测后选取2个代表菌株进行形态学研究,并基于ITS和LSU基因进行系统发育分析。结果表明,2个病原菌菌株为小球腔菌科Leptosphaeriaceae拟链格孢属Alternariaster向日葵拟链格孢Alternariaster helianthi。

Alternaria helianthi has been used as the scientific name of the pathogen causing oil sunflower black spot in China.However,it has been renamed Alternariaster helianthi internationally.The samples of leaf black spots of Helianthus annuus were collected from Huayin city,Shaanxi province in 2017.The causal agent was obtained from the symptomatic samples by single spore isolation.Two representative strains were selected after pathogenicity tests to determine their morphology and conduct multi-gene phylogenetic analysis based on ITS and LSU gene.The results showed that the two pathogenic strains were Alternariaster helianthi in Alternariaster genus of Leptosphaeriaceae family according to comparison their morphological and molecular characteristics with the relevant species.