【摘要】 用17个引物对不同地理来源的4种11株座壳孢 Aschersonia 进行 RAPD 分析,结果表明,种间和种内具丰富的遗传多样性,菌株间差异与地理来源和寄主不相关。部分菌株和 GenBank 上的座壳孢属核糖体 nrDNA 大亚基序列进一步用于该属系统发育研究。系统发育树反映的种间和种内关系与形态分类结果基本一致,可以将不同地理来源的不同种区分开来,但从同科或同目寄主昆虫上分离到的不同种并不具有相近的亲缘关系。同时进化树还表明,所分离的菌株 Aa 是粉虱座壳孢(Aschersonia aleyrodis Webber)。此外,对相同的供试菌株两技术所反应的亲缘关系趋势相同,表明 RAPD 技术和 LSUrDNA用于座壳孢的亲缘关系分析和种类鉴定均是可行的。更多还原

【Abstract】 Eleven isolates within four species of the entomogenous fungus Aschersonia from China,USA,Japan,Philippines, Malaysia and Columbia were characterized using 17 RAPD primers.The genetic diversity among these strains of Aschersonia was found.The clustering results showed that the genetic variability among interspecies was more than that among intraspecies of Aschersonia.In the constructed phylogenetic tree,these isolates were not clustered according to their geographical origins or hosts. Furthermore,the sequences of the divergent domain at the 5’end of the large subunit rRNA gene from the mitosporic entomogenous fungi were employed to analyze the phylogenetic relationships of 11 Aschersoaia isolates.The relationships of interspecies or intraspecies showed in phylogenetic tree were nearly consistent with the results of morphological study.Different species isolated from different geographic origins could be clearly distinguished in the tree.But there were no close relationships among species isolated from the same family or order of insect hosts.The tree indicated that isolate Aa belonging to Aschersonia aleyrodis was the same as Aa992 and Aa3.4485.Moreover,the results of RAPD analysis were consistent with those of LSU rDNA analysis for the same isolates tested,which consequently indicated that both methods could be independently applied for classification and identification of Aschersonia.更多还原