西瓜品种间亲缘关系的AFLP分析

为了解西瓜品种间的亲缘关系,利用AFLP指纹图谱分析技术,对48个国内外西瓜品种进行了基因组DNA多态性分析。结果表明:11对AFLP引物共产生490条DNA带,平均每个引物组合扩增出44.5条带,其中,96条为多态性带,占总带数的19.6%;根据DNA谱带计算品种间遗传相似系数,其变化范围在0.32~0.95之间,平均相似系数为0.82,说明西瓜品种间同源性较高,遗传基础狭窄。用NTSYS软件进行聚类分析,48个西瓜品种被划分为6个类群(Watermelon groups,简称WGs)。其中WGI和WGII分别包括30、14个西瓜品种,两者占总数的91.7%。其余WGIII、WGIV、WGV和WGVI均包括1个品种,它们都与WGI和WGII之间有较大的差异。WGI又分为5个亚群,其中WGI-1品种最多,占60%;WGII又分为3个亚群,其中WGII-2含品种最多占85.7%,说明多数品种亲缘关系较近,只有少数品种亲缘关系较远。此外,本研究表明,AFLP指纹分析技术具有很高的分辨率,能够揭示西瓜品种间的差异,是鉴定西瓜品种的有力工具。

AFLP analysis on sibship of watermelon cultivars

In order to know the relationship among the watermelon varieties,48 watermelon cultivars from China and abroad were analyzed using AFLP.The result showed that 490 AFLP bands were amplified using 11 primer pairs among them,96(19.6%)bands were polymorphic.Based on DNA bands,the similarity coefficient were calculated and their average value was 0.82,ranging from 0.32 to 0.95,which indicated that sibship was close and their genetic base was narrow among cultivars of watermelons.When all of the polymorphic bands were analyzed by cluster analysis,48 cultivars were classified into 6 groups(WGs).WGI included 30 cultivars and WGII,14 both of them accounted as much as 91.7%.The other WGs consisted of 1 cultivar,respectively,which were more different from the cultivars of WGI and WGII.Furthermore,the WGI could be divided into 5 subgroups,and 60% of the cultivars in this group fell into the WGI-1.There were 3 subgroups involved in WGII,and the cultivars of WGII-2 accounted for 85.7%.The analysis showed that there existed close sibship among the majority of watermelon cultivars.In addition,this study demonstrates that AFLP fingerprinting has higher resolution and can reveal the difference of cultivars,so it is an efficient tool.