八仙花叶斑病病原的分离与鉴定

Isolation and identification of the pathogen causing leaf spot on Hydrangea macrophylla

八仙花[Hydrangea macrophylla (Thunb.)Ser.],又名绣球花、粉团花等,在城市现代公园和风景区建设中占据重要地位。八仙花在生长期常受到多种病原物危害,其中叶斑病发生普遍,病原种类复杂。已报道病原包括短小茎点霉(Phoma exigua)、交链格孢(Alternaria alternata)、极细枝孢(Cladosporium tenuissimum)、多主棒孢(Corynespora cassiicola)等[1-4]。2021年8月课题组在北京市丰台区发现八仙花叶斑病为害严重。

Hydrangea macrophylla(Thunb.)Ser.plays an important role in the urban landscape construction since the beautiful flower type and color.In August 2021,a severe outbreak of leaf spot was observed on H.macrophylla in the flower garden of Fengtai district,Beijing.The fungus was isolated by tissue separation me-thod,and its pathogenicity was confirmed based on the Koch’s postulates.According to morphological features and phylogenetic analysis of rDNA-ITS,TUB and RPB2 genes,the pathogen was identified as Epicoccum sorghinum.To our knowledge,this is the first report of E.sorghinum causing leaf spot on H.macrophylla in China,which will provide scientific basis for effective control of the disease on H.macrophylla.