利用SSR和Indel对大翼橙种质的遗传多样性及群体结构分析

元江宜昌橙(Citrus ichangensis Swingle)是云南元江县新发现的一类原始野生宜昌橙资源,为了解元江宜昌橙与长江流域来源的宜昌橙的遗传差异,以及云南元江野生宜昌橙种群内个体间的遗传差异,本研究利用21对SSR和InDel引物对元江宜昌橙、长江流域宜昌橙、大翼橙、香橙等4个群体的48份资源材料进行了遗传多样性分析。研究结果表明,21对引物共产生了131条多态性条带,平均每对引物检测到6.2个多态性条带,多态性标记位点的香农信息指数为0.14~1.11,平均期望杂合度为0.04~0.97。群体遗传结构分析、UPGMA聚类分析和主成分分析均表明元江野生宜昌橙是不同于长江流域宜昌橙资源的新类型,4个群体间的遗传差异较大,但群体间的基因流较低。在元江宜昌橙种群内存在遗传异质个体,但种群内的遗传多样性比长江流域宜昌橙群体的遗传多样性水平低,香橙群体的遗传多样性水平较高,大翼橙群体中的马来西亚大翼橙与宜昌橙遗传距离较远,而红河大翼橙与元江宜昌橙的遗传距离较近。本研究证实了元江野生宜昌橙是有别于长江流域宜昌橙的新类型,在进行元江宜昌橙野生资源的收集时,以居群为单位加以资源材料的收集对遗传多样性的保护更为有利。

Genetic Diversity and Structure Analysis on Papeda Germplasms Using SSR and InDel Markers

Yuan Jiang ichang papeda (Citrus ichangensis Swingle) is a kind of wild ichang papeda recently found in Yuan Jiang county, Yunnan province. To learn the genetic diversity of papeda populations from Yuan Jiang and other origins, 48 papeda germplasms divided into four populations namely as Yuan Jiang ichang papeda, Yangtze River ichang papeda, Honghe papeda (Citrus hongheensis Y. L. D. L.)and Xiang Cheng (Citrus junos Siebold.ex Tanaka)were examined with 21 pairs of SSR and InDel primers. A total of 131 polymorphic bands were obtained by 21 primer pairs, in average 6.2 polymorphic bands per pair primer. The Shannon information index of the polymorphic sites were 0.14-1.11, and average expected heterozygosity were 0.04-0.97. Population genetic structure analysis, UPGMA cluster analysis and principal component analysis all showed that Yuan Jiang ichang papeda was new accessions different from the ones found in Yangtze River Basin. The genetic variance among populations were tested and the gene flow among populations were relatively low. Although genetical heterogeneous individuals were found in Yuan Jiang ichang papeda population, the genetic diversity within the population was lower than that of Yangtze river ichang papeda and Xiang Cheng population had the highest genetic diversity. Malaysian papeda is obviously divergent from ichang papeda, while the genetic distance between Honghe papeda and Yuan Jiang ichang papeda are close. This study indicated that Yuan Jiang ichang papeda was a new accession divergent from the one originated in Yangtze River Basin. When collecting wild germplasm of Yuan Jiang ichang papeda, populations sampling strategy should be prior for protecting this endangered species.