扁桃杧(Mangifera persiciformis)遗传多样性的AFLP分析

Genetic diversity of Biantaomang(Mangifera persiciformis) verified by AFLP marker

采用AFLP分子标记技术,对中国特有杧果野生近缘种扁桃杧种质资源8个居群的遗传多样性进行了研究。利用筛选出的8对AFLP引物,共扩增出612条谱带,其中514条多态性带,占83.99%。扁桃杧不同居群间遗传多样性水平差异较大,多态位点百分率在68.20%～80.70%、有效等位基因数在1.429～1.570、Nei基因多样性指数在0.270～0.321、Shannon信息指数在0.408～0.465。扁桃杧遗传多样性主要存在于居群内,但Nei遗传分化系数和AMOVA分析表明群体间已发生了一定程度的遗传分化(Gst和Фst分别为0.139和0.198)。根据Nei遗传距离对不同群体进行UPGMA聚类分析,表明扁桃杧自然群体的遗传距离与地理位置有密切的关系,Mantel检验表明遗传距离与地理距离有显著的正相关关系。

Levels of genetic diversity within and among 8 natural populations of Mangifera persiciformis C.Y.Wu et T.L.Ming were analyzed by AFLP markers.A total of 612 fragments were generated from 8 pairs of selective AFLP primer combination,514（83.99%） of which were polymorphic.Genetic diversity difference among populations was relatively high based on the percentage of polymorphic loci ranged from 68.20% to 80.70%,effective number of alleles ranged from 1.429 to 1.570,Nei＇s gene diversity index ranged from 0.271 to 0.321,and Shannon＇s information index ranged from 0.408 to 0.465.Genetic differentiation mainly occurred within populations.However,some genetic differentiation had occurred among populations（Gst=0.139,Фst=0.198）according to Nei＇s Gst value and analysis of molecular variance（AMOVA）.The genetic distance among Mangifera persiciformis C.Y.Wu et T.L.Ming populations had a close relationship with the geographical distance according to UPGMA cluster analysis based on Nei＇s genetic distance.The Mantel test showed that genetic distance was positively correlated with geographical distance.