白芷黑斑病病原菌鉴定及病害发生规律研究

对四川白芷黑斑病的症状、病原菌致病性和形态特征等进行了研究,确定病原菌为当归叶点霉(PhyllostictaangelicaeSaccardo)。经两年的田间病害发生动态调查,该病在四川始发期为3月上旬,高峰期为6月份,病株率达100%,病叶率达74.51%。病害的初侵染源主要是留种株的病叶和田间病残体。病菌分生孢子借雨滴飞溅的方式传播,并在白芷生长期中不断引起再侵染。

Identification of the pathogen of Angelica black spot and its occurrence

The pathogen of Angelica black spot was identified as Phyllosticta angelicae Saccardo.The results from the investigation of two years in the field showed that the disease first appeared in Sichuan during early March,with a peak in June.The highest percentage of diseased plants and leaves were 100% and 74.51%,respectively.The diseased leaves on the seed plants and the residues of infected leaves in the field were the primary infectious source.The conidia were released from conidiocarp,and then transmitted by rain as reinfection sources.