毛木耳种质资源的RAPD分析

利用22个随机引物对来源不同的56个木耳菌株进行了RAPD分析。结果表明,所有引物的扩增产物DNA片段均表现出明显的多态性,供试菌株总共扩增出164条多态性片段,占总扩增片段的99%;供试菌株两两间的遗传相似系数变化较大(平均GS值0.2143￣0.8764)。采用系统聚类法中的类平均法,对供试的所有菌株两两间相似系数进行聚类,可将它们分为四大类,各大类的类间和类内菌株的遗传变异程度较大,以IV类内各菌株间的最高(平均GS值0.3891),II和III类间的最低(平均GS值0.5887),表明遗传变异也较丰富(总平均GS值0.4918)。将RAPD技术应用于不同菌株间遗传差异的研究,具有反应迅速、不受外界环境条件影响、能从DNA分子水平上揭示菌株间遗传差异等优点,是一种快速准确评估木耳种质资源的有效方法。

Studies on Germplasm Resources of Auricularia polytricha by Random Amplified Polymorphic DNA

The random amplified polymorphic DNA(RAPD)analysis was conducted with 22 ten-nucleotide random primers in 56 strains of A.polytricha collected from various localities.The results revealed that the amplified DNA fragment from all the random primers were of obvious polymorphism.In total,164 polymorphic DNA fragments were amplified,which accounts for 99% of total amplified fragments.The genetic similarity coefficient between each in all the tested strains of A.polytricha differed widely ranged from 0.2143~0.8764.The cluster analysis based on the coefficient of genetic similarity between the tested strains of A.polytricha was carried out by UPGMA and the 56 tested strains were subdivided into four groups.There were great degrees of genetic diversity between strains of intra-groups and inter-groups.And it was found that the degree of genetic diversity between strains of group IV with an average similarity coefficient of 0.3891 was the highest in all groups,and that the degree of genetic diversity between strains in group II and III with an average similarity coefficient of 0.5887 was the lowest.In terms of all the strains tested the degree of genetic variability as a whole was also significant with a total average similarity coefficient of 0.4918.The application of RAPD technique in studying genetic differences between various strains had a lot of advantages such as reacting fast,not being influenced by outer environment and showing genetic diversity among strains on the level of DNA molecule.So,RAPD analysis technique might be ascribed as an effective method to rapidly evaluate germplasm resources of A.polytricha.