利用不同来源的棉花品种（系）分析染色体多态性

利用不同来源的棉花品种（系）分析染色体多态性 利用不同来源的棉花品种(系)分析染色体多态性 农学专业学生 叶文雪 指导教师 郭旺珍 摘要:利用109份不同来源、不同地域、不同时间推广的棉花主栽品种(系)为研究材料， 对覆盖异源四倍体棉花基因组的177个EST-SSR引物揭示的基因位点，进行不同棉种染色 体多态性分析。EST-SSR的扩增结果被分为两类:一类是在供试品种中呈单态性位点，由 133对引物到;另一类是在供试品种中呈多态性位点，由44对引物检测到。这177对 引物共获得了194 个多态性位点和133个单态性位点，分布在26条染色体连锁群上。每条 连锁群上可以检测出2-16个位点，平均6.81个，其中多态性位点8.81，单态性位点5.54。 研究表明并不是所有的染色体位点都具有遗传变异性，一些染色体位点具有很强的保守性如 Chr1、Chr4、Chr16、Chr17、Chr22、Chr26只具有单态性位点，表明在不同年份，对不同 品种使用不同的育种培育过程中，该条染色体上涉及的基因位点均有很强的保守性;一 些染色体位点具有很强的变异性如Chr15只具有多态性位点，表明在不同年份，对不同品种 使用不同的育种方法培育过程中，该条染色体上涉及的基因位点具有很强的变异性，可能是 育种目标性状涉及的位点，有利于遗传改良和遗传育种。同时对多态性位点进行了聚类分析， 聚类分析显示:利用EST-SSR分子标记技术，棉花染色体多态性可以有效的揭示棉花品种 的遗传多样性。 关键词:棉花，染色体，多态性，EST-SSR，聚类分析 The Analysis of Chromosome Diversity from Different Origin Cotton Cultivars (Lines) Student majoring in Agronomy Ye Wenxue Tutor Guo Wangzhen Abstract:The objective of the present study was to make use of effective molecular marker systems to reveal chromosome diversity among 109 different cotton cultivars (lines) from home and abroad by using177 primer pairs of EST-SSR. These EST-SSR analysis showed that the amplification products of 177 pairs of SSRs were separated into two parts: one owned 133 monomorphic bands amplified by 133 primer pairs; the other did polymorphic bands by 44 primer pairs, which these loci were covered all 26 chromosome (linkages). There are 194 polymorphism bands and 133 simple bands detected. The avenge number of alleles per SSR loci was 6.81 with a range of 2-16. Among these loci, Polymorphic loci were 8.81 and monomorphic loci were 5.54. The research showed that not all chromosomes owed polymorphic loci, some Chromosomes were conservative such as Chr. 1, Chr. 4, Chr. 16, Chr. 17, Chr. 22 and Chr. 26, which indicated that these loci were not easily modified in the process of new cultivar development. Nevertheless, Chr 15 with polymorphism band showed the loci located on the chromosome was changeable that it was helpful to new agronomic traits selection. Further, polymorphism bands were also carried out cluster analysis. The research showed that chromosome diversity of cotton can be effectively detected by using EST-SSR markers. Key words: Cotton, Chromosome, Diversity, EST-SSR, Cluster analysis