利用ISSR-PCR技术分析香蕉枯萎病菌的遗传多样性

Genetic diversity analysis of Fusarium oxysporum f.sp.cubense populations from China using Inter-Simple Sequence Repeats-PCR (ISSR-PCR) technique

摘要:

摘要:【目的】应用简单序列重复区间(inter-simple sequence repeats，ISSR)分子标记技术对全国主要香蕉产区95个香蕉枯萎病菌菌株进行ISSR分析，了解其遗传多样性，为香蕉品种的合理布局及枯萎病的防治提供理论依据。【方法】选用8条引物，对香蕉枯萎病菌进行ISSR-PCR分析，采用NTSYSpc v2. 10e软件分析其遗传结构。【结果】从33条随机引物中筛选出8条重复性好、特异性高的引物，共产生52个ISSR分子标记，其中92.3%的片段具有多态性。菌株间的Nei 遗传距离(D)为0.57－1.00，供试菌株以遗传距离为0.68阀值可以分为A、B、C、D、E、和F共6个类群，所占的比例分别为51.06%、5.20%、2.08%、39.58%、1.04%、1.04%。【结论】病原菌菌株间的遗传变异很大，差别很明显，ISSR聚类组群的划分与病原菌的寄主和小种有很明显的相关性。

关键词:关键词:香蕉枯萎病菌，遗传多样性，ISSR分析

Abstract:

Abstract:［Objective］We used Inter-Simple Sequence Repeats (ISSR) markers to reveal the genetic diversity of 95 Fusarium oxysporum f．sp．cubense (FOC) isolates from banana in China，for the rational control of the disease．［Methods］ Eight primers were chosen for analyzing FOC isolates to study their genetic diversity by ISSR-PCR． All isolates were clustered using Unweighted Pair-Group Method with Arithmetic means ( UPGMA) analysis by NTSYSpc v2.10e software.［Results］A total of 52 sites were generated，among them 92. 3% were polymorphic．Genetic distance was 0.57 to 1.00 based on the Nei’s standard． Isolates were grouped into six distinct clusters (A，B，C，D，E and F)based on ISSR analysis using a genetic distance threshold of 0.68，the proportion of 51.06%，39.58%，5.20%，2.08%，1.04%，and 1.04%，respectively.［Conclusion］There were high levels of genetic variation among the FOC isolates，and the ISSR clustering groups had obvious correlation with hosts and races of the pathogen.

Key words:Keywords: Fusarium oxysporum f．sp．cubene，genetic diversity，ISSR