怀黄菊黑斑病病原的分离及鉴定

Isolation and Identification of Pathogen Causing Black Spot Disease of Chrysanthemum morifolium‘Huaihuang'

对怀黄菊(Chrysanthemum morifolium Ramat.‘Huaihuang’)上发生的一种叶片变黑枯死的主要病害进行了病原分离和鉴定,通过形态观察、产孢表型分析、致病力检测和r DNA-ITS序列分析,初步确定该病是由链格孢属(Alternaria)的交链孢菌(Alternaria sp.)引起的怀黄菊黑斑病。从发病植株中分离纯化得到2个致病菌株A1和A2;PDA培养基上的2个致病菌株菌落质地、颜色、边缘整齐度等特征存在一定差异,显微镜下产孢表型也存在差异,但致病力没有差异,其r DNA-ITS序列一致性达100%,序列已在Gen Bank上登录,登录号为KF688111。

A pathogen causing leaf black spot of medicinal Chrysanthemum morifolium‘Huaihuang'was isolated and characterized based on the morphological features,phenotypic analysis of spore production,pathogenicity test,and sequence analysis of internal transcribed spacer region of the ribosomal DNA(r DNA-ITS). The results showed that the black spot disease was caused by Alternaria sp. A1 and A2,two pathogenic strains,were obtained from the diseased plants. Although isolates A1 and A2 showed some variations on colony texture,color,edge uniformity,and sporulation phenotype,there was no significant difference in their pathogenicity to Chrysanthemum morifolium‘Huaihuang'leaves. The r DNA-ITS sequence of the two fungi strain showed 100% identity. The sequence of the identified fungus has been submitted to Gen Bank(Gen Bank accession number:KF688111).