草坪草腐霉枯萎病菌的分离鉴定及其对高羊茅的致病性

Isolation and Identification on Pathogen of Turfgrass Pythium Disease and Its' Pathogenicity to Tall Fescue

对采自高尔夫球场内11份早熟禾的腐霉病株进行分离培养,形态学鉴定为瓜果腐霉。生物学测定结果表明,其最适生长温度是35℃,在25～35℃时生长速度最快;最适pH值为7.5,在pH值为6～9时生长较好;通过rDNA-ITS序列测定和同源性比较也表明,菌株是瓜果腐霉,用MEGA5.0软件构建系统发育树得到,与该菌株遗传距离最近的腐霉是AF452151;对高羊茅品种美洲虎4号(Jaguar 4G)的致病性试验测定表明,该菌株为致病菌。

Eleven Pythium strains collected from the golf course was isolated,cultured,and identified as Pythium aphanidermatum based on morphology.The Pythium strain＇s optimum growth temperature was 35℃,and the Pythium strain grew fast at 25～35℃.The optimum pH value was 7.5,and the strain grew well in the pH value of 6 to 9.rDNA-ITS sequence of the strain determination and homology comparison revealed that the strain was Pythium aphanidermatum.The phylogenetic tree was constructed using MEGA5.0 software,and knew that the Pythium AF452151 and the Pythium strain had the nearest genetic distance based on the phylogenetic tree.Strain with strong pathogenicity was selected through pathogenicity test on Jaguar 4G.