草菇栽培菌株DNA多态性的PCR-RFLP和RAPD分析

12个草菇栽培菌株的核糖体DNA（rDNA）、线粒体DNA（mtDNA）和基因组总DNA的多态性被研究了。应用PCR－RFLP技术，扩增了rDNA5.8s+ ITS区段及mtDNA小区段,并进行限制性酶切分析,结果表明菌株间的rDNA在5.8s+ ITS区段的遗传差异小，据此只能将测试的12个菌株分为两类；而对mtDNA小区段的检测未能显示出菌株间的差异，表明测试的菌株在所研究的区段具有很高的遗传相似性。在此基础上，对基因组总DNA的RAPD分析表明，菌株两两间的遗传相似系数在0.554到0.898之间，而平均相似系数为0.707。通过平均链锁聚类方式(UPGMA)聚类,发现在相似系数0.710水平上，供试菌株可分为四大类。这些研究结果为草菇的育种提供了科学依据。

Studies on DNA Polymorphism of the Cultivated Strains of Volvariella volvacea by PCR-RFLP and RAPD Techniques

The polymorphisms of rDNA, mitochondrial DNA (mtDNA) and total genomic DNA were examined in 12 cultivated strains of V. volvacea. By PCR-RFLP technique, two regions of rDNA5.8s+ITS and small mtDNA were successfully amplified, respectively. The amplified products were subsequently digested with special restriction endonucleases. The results showed that genetic diversity was small within the two regions for 12 strains. According to the restriction fragment patterns of rDNA 5.8s+ITS by HinfⅠand Sau3A, 12 strains could be divided into two groups. For small mtDNA, however, all restriction fragment patterns confirmed that there was no variation in 12 strains. The total genomic DNA was then examined by sensitive RAPD technique. The results showed that genetic similarity coefficients between the strains were within a range from 0.554 to 0.898, while average similarity coefficient between them was 0.707. Furthermore, 12 strains could be divided into 4 groups based on the level of similarity coefficient 0.710 by cluster dendrogram. These results provided the genetic foundation for the breeding of V. volvacea.