天津地区草坪腐霉枯萎病病原鉴定及生物学特性研究

Study on identification and biological characteristics of Pythium diseases of turfgrass in Tianjin

连续3年对天津地区草坪腐霉枯萎病病害发生调查，总结出病害发生规律：高温高湿的气候条件是腐霉枯萎病发生的主要因素，天津地区的病害发生期主要有两个：（1）苗期（8月下旬～9月下旬），造成幼苗猝倒；（2）7月下旬～8月中旬的夏季，造成大面积坏死枯草斑。通过病原茵致病性测定，筛选强致病性菌株，并鉴定其为瓜果腐霉（Pythium aphanidermatum）。通过对其生物学特性研究表明，病原茵生长的最适温度为35℃，最适pH值为7．0～8．0，最适碳源为可溶性淀粉，其次是蔗糖，且差异显著（P〈0．05）。

The occurrence pattern of pythium diseases of turfgrass in Tianjin was investigated for 3 years and the results suggested that the main factor of the disease was the climate condition, i. e, , high temperature and high moisture. There were two periods for pythium disease occurrence in Tianjin area. The first period was from late August to late September and the second was from late July to mid August. The main symptoms was damping off in seedling stage and death of large area. Strain with strong pathogenicity was selected through pathogenicity test and was identified as Pythium aphanidermatum. The suitable culture temperature was 35 ℃ and suitable pH value was 7.0 to 8.0, suitable carbon source was sugar or soluble starch.