关键词: 瓜类寄主, 尖孢镰刀菌, 互作, 牡丹, 黑斑病, 链格孢, ITS序列分析, 鉴定

Abstract: The pathogens of tree peony black spot remained unclear. The aim of this research was to clarify its taxonomic status by identifying the pathogen of tree peony black spot. In this study，the pathogen was identified based on morphology and molecular identification，the ITS phylogenetic trees was generated with the soft of Mega 5. The result suggested that the pathogen of tree peony black spot was Alternaria alternate（Genbank Accession No. KJ682317）. The homology between the sample strain and A. alternate was up to 100 percent. The wound leaves and the intact ones were both infected by the pathogen. However，the expansion rate of the disease spot on the wound leaves was faster than the intact ones.

Key words: cucurbit, Fusarium oxysporum, Interaction, tree peony, black spot, Alternaria alternata, analysis of ITS sequence, identification