中国香菇自然种质的rDNA遗传多样性分析

GENETIC DIVERSITY OF NATURAL GERMPLASM OF LENTINULA EDODES IN CHINA INFERED FROM rDNA SEQUENCES

测定了全国范围内的59个野生香菇菌株rDNA的ITS区域的序列。所得序列的总长度在723-727个碱基之间,G+C含量也基本稳定在57.5%左右。用Phylip3.6软件包对59个ITS序列进行DNA数据分析。结果表明59个菌株被划分到3个不同的谱系中,其中谱系Ⅰ包括11个菌株,分布较为均衡,涉及东北、西北、西南和东部沿海等地区的8个省份;谱系Ⅱ包括14菌株,以西北、西南的4个省份为主;谱系Ⅲ包括34个菌株,覆盖范围最广,除东北和西北高原地区外,其它均有涉及。地缘关系分析表明以陕、甘为主的西北高原地区的菌株涉及Ⅰ、Ⅱ两个谱系;以闽、浙、赣和台湾为主的东部沿海地区的菌株涉及Ⅰ、Ⅲ两个谱系;而以云、贵、川为主的西南地区的菌株则覆盖到了所有的3个谱系。这三个地区的香菇遗传多样性最丰富,西南地区尤为突出,是香菇种质资源保护与利用的重点区域。

ITS regions of rDNA of 59 wild Lentinula edodes isolates in China were sequenced. The sequence lengths of this region are ranged from 723 to 727bp, and the G+C proportion approximately stabilized in 57.5 percent. The DNA data of 59 ITS sequences was analyzed with Phylip3.6package. Results revealed that all the 59 isolates were divided into three lineages. 11 isolates were included in lineageⅠ, which covered 8 provinces of northeast, northwest, southwest and east coastland of China. LineageⅡcomprised 14 isolates mainly come from 4 provinces of northwest and southwest China. All the other 34 isolates are involved in lineage Ⅲ, which distributed in all the 12 provinces except 3 in northeast and northwest China. Regional relationship of the isolates showed that isolates of northwest plateau, mainly collected in Shanxi and Gansu province , are contained in lineageⅠand lineageⅡ; the isolates came from provinces of east coastland, Zhejiang, Fujian, Jiangxi and Taiwan, just distributed in lineageⅠand lineageⅡ; and the isolates came from Yunnan, Guizhou and Sichuan where located in southwest China are separated into all the three lineages; All the three areas, especially the southwest China, have the most plentiful genetic diversity of lentinula edodes germplasm, where the genetic resource of lentinula edodes would be utilized and conserved sufficiently.