花生白绢病菌ITS分型、菌丝亲和群分析及相关生物学特性比较

2013~2016年从全国12个省市采集不同花生白绢病样本,共分离获得39个分离物,对其ITS-r DNA序列进行了分析,表明它们均属于齐整小核菌(Sclerotium rolfsii);这39个分离物分为两个亚组,分别包含22个和17个菌株;对这39个菌株进行了菌丝亲和群分析及相关生物学特性比较,共鉴定出23个菌丝亲和群;8个亲和群包含2~6个菌株,其余的15个亲和群都只包含1个菌株;同一菌丝亲和群的菌株菌落形态相似,大多数菌株的菌丝生长速度、菌核大小比较相近,个别菌株差异较大;39个菌株均能产生草酸,在菌落形态、菌丝生长速度、菌核大小和重量上均有差异,生长速度为0.47~2.32cm·d~(-1),菌核直径为0.71~1.87 mm,单粒菌核干重为0.24~2.64 mg。

Analysis of genetic variation among Sclerotium rolfsii isolates from China based on mycelial compatibility groups,ITS sequence and biological characteristics

The total of 39 isolates were collected from peanut plants with southern stem rot symptoms in 12 provinces of China from 2013 to 2016. All the isolates belonged to Sclerotium rolfsii based on the ribosomal DNA internal transcribed spacer (rDNA-ITS) sequences, and were classified into two groups in which one contained 22 isolates and the other contained 17 isolates. The 23 MCGs (mycelial compatibility groups) and related biological characteristics were determined for the 39 isolates, in which 8 MCGs contained 2 to 6 isolates and the others contained only one isolate. The colony morphology of strains in the same mycelial group was similar, and the mycelial growth rate and sclerotia size among most strains were similar, but the individual strains were different. All the isolates could produce oxalic acid and exhibited significant differences in colony morphology, growth rate, sclerotia size and weight with the growth rate from 0.47 to 2.32 cm·d^-1, the sclerotia diameter from 0.71 to 1.87 mm and dry weight for single sclerotia weight from 0.24 to 2.64 mg.