黄山球孢白僵菌野生种群流行菌株的28S rDNA Ⅰ型内含子分析

A 28S rDNA Group I Intron Analyses of the Native Prevailing Stains of Beauveria bassiana in Huangshan Mountains

通过4对引物,对采自黄山的40株球孢白僵菌菌株进行28S rDNA I型内含子分析,以探讨黄山自然种群的遗传结构及流行菌株类型。结果显示,在黄山球孢白僵菌自然种群中,存在着13种不同的内含子单倍型,显示出在黄山小范围内的球孢白僵菌种群也存在着丰富的遗传多样性。不同单倍型在种群中所占的比例不同,其中BBBA型占据主导地位,为37.5%,ABAA型和ABBA型次之,分别为15%和12.5%,而BABA等7种单倍型则各仅占2.5%,反应出不同的遗传背景的菌株具有不同的遗传稳定性与环境适应性。数据同时显示,同核体菌株在黄山球孢白僵菌自然种群中的比例为82.5%,显示出同核体在遗传稳定性上优于杂核体,但同时,17.5%的杂核体比例也显示出准性生殖在球孢白僵菌种群中的普遍性。

To study the genetic diversity and genotype of the native prevailing strains, a 28S rDNA group I intron marker-based genetic analysis was performed on 40 fungal strains representing the native population of Beauveria bassiana in Huangshan Mountain region. A diversity of 13 halpotypes appeared in the fungal population. Among them, the genotype BBBA dominated the fungal population at a frequency of 37.5%, and the genotypes ABAA and ABBA followed by 15% and 12.5%, respectively, whereas others 7 genotypes such as BABA only occupied a percentage of 2.5 % for each. The different genotype frequency showed the strains of B. bassiana with and ecological adaptability. A high percentage homokaryotic strains was much higher than that different genetic background had different genetic stability of 82.5 % for homokaryon revealed the genetic stability of of heterokaryotic strains, but the heterokaryon occupied a ratio of 17.5% to the total also showed the universality of parasexual recombination of genetic material.