苦荞SSR引物开发及其在遗传多样性分析中的应用

Development of SSR Markers and Application in Analysis of Genetic Diversity in Tartary Buckwheat(Fagopyrum tataricum)

苦荞在中国已经成为广受欢迎的健康食品。本研究通过选择性扩增微卫星序列、体外重组扩增产物和构建SSR富集文库,开发出了一种简便的重组微卫星引物设计方法。通过这种方法,设计合成500对SSR引物,在苦荞上的有效性约50%,多态率达10.8%,PIC平均值为0.3600。利用其中的28对SSR引物,在苦荞核心种质中检测出等位基因85个,每位点的等位基因数为2～5个,平均3.0个。不同地理来源的苦荞种质资源的Shannon-Weaver多样性指数为0.3633～0.6671,来自云南、四川和西藏的苦荞材料不但遗传多样性丰富,而且亲缘关系较近,进一步证实苦荞起源于中国西南部。本研究证明重组微卫星引物设计方法开发的引物对苦荞非常有效,将有助于促进苦荞种质资源遗传多样性、有用基因发掘和分子标记辅助育种研究。

Tartary buckwheat has become a popular health food in China.In the current study,through selectively amplifying microsatellite-containing sequences,recombining the amplicons by redigestion and ligation,and constructing SSR loci library,an effective method of recombinant microsatellite amplification was developed.With this method,we designed 500 pairs of primers and tested tartary buckwheat.The effectiveness of these SSR primers in tartary buckwheat was about 50%,the polymorphic rate was 10.8%,and the average value of PIC was 0.3600.We analyzed the genetic diversity of core collection of tartary buckwheat with 28 SSR markers.A total of 85 alleles were identified,ranging from 2 to 5 with an average of per locus.Shannon′s information indices of geographical variation ranged from 0.3633 to 0.6671.The accessions from Yunnan,Sichuan and Tibet were not only abundant in genetic diversity but also had the closely phylogenetic relationship.This result further confirmed that tartary buckwheat originated from Southwestern China.This study demonstrates that the recombinant microsatellite amplification method for development of SSR primers in tartary buckwheat would be very effective,and will contribute to the researches on genetic diversity analysis,identification of useful traits,and marker-assistant breeding in tartary buckwheat.