摘要
为了调查北京地区苗圃基地的腐霉属种类,采用花瓣、叶片诱捕法对采集到的土样进行诱导,以分离出腐霉菌。结果表明:有5株形态相似的菌株在形态及培养形状上较为一致,且异于中国已报道的其他腐霉种。运用改进的CTAB法提取菌株的基因组DNA,测定其rDNA-ITS序列,并与模式菌株CBS808.96进行多重序列比对,相似度为99.26%。选取与Pythium nunn同组的所有腐霉种以及其他组别的部分腐霉种,以Phytophthora polymorphica为外类群,采用NJ法构建了系统进化树。根据形态特征及分子序列分析结果,将此5株菌株鉴定为Pythium nunn。Pythium nunn是一种具有生防潜力的卵菌,可以为后续的生物防治研究提供试验基础。
Pythium species were isolated by using petal and leaf baiting methods from soil samples that collected from some nurseries in Beijing in order to realize their distributions.The results showed that there were 5 isolates similarly in morphology and colony and had some differences with other Pythium species already reported in China.Genomic DNA of these 5 isolates were extracted by the improved CTAB method.Multiple sequence alignment was conducted with the type strain CBS 808.96 in terms of the rDNA-ITS sequences,and the result showed that there was a high similarity（99.26%） between them.All the species of the Pythium group which Pythium nunn was in and some species from other groups were selected to be constructed the phylogenetic tree with the method of neighbor-joining.The tree was rooted using Phytophthora polymorphica as an outgroup.Based on the morphological characteristics and the results of sequence analysis,5 isolates recorded in this article were identified as Pythium nunn.Pythium nunn is a potential biocontrol agent that provides test basis for follow-up studies in biocontrol area.
出处
《中国农学通报》
CSCD
2012年第18期199-204,共6页
Chinese Agricultural Science Bulletin
基金
国家林业局"948"项目"栎树疫霉猝死病菌等森林疫霉检测鉴定技术及风险预警系统的引进"(2009-4-35)
关键词
腐霉
形态特征
RDNA-ITS
系统学
生物防治
Pythium nunn； morphological characteristics； rDNA-ITS； phylogenetic； biocontrol
