中国特有植物卧龙沙棘自然群体的RAPD分析

应用12个随机引物对卧龙沙棘全部2居群共28个个体进行了RAPD分析。结果表明,卧龙沙棘具有较丰富的遗传多样性,多态位点百分率为78.05%,Nei’s基因多样性h=0.2553,Shannon’s多态性信息指数Ι=0.3841。分布范围狭窄的卧龙沙棘在亚种水平的遗传多样性明显高于分布较广的中国沙棘。在居群水平上,卧龙沙棘同样具有很高的遗传多样性,平均多态位点百分率为63.42%,Nei’s基因多样性h=0.2193,Shannon’s多态性信息指数I=0.3287。卧龙沙棘的基因分化系数Gst=0.1425,表明遗传变异主要存在于居群内。AMOVA的结果也表明,在全部的遗传变异中,19.18%的遗传变异存在于居群之间,与Gst值基本一致。这一结果符合卧龙沙棘风媒、异交的繁育系统特点。

RAPD analysis of natural populations on Chinese endemic Hippophae rhamnoides ssp.wolongensis(Elaeagnaceae)

12 primers were used to examine gene diversity of H.rhamnoides L.ssp.wolongensis by random amplified polymorphic DNA (RAPD). 78.05% in total of the scorable markers were polymorphic at subspecies level. Nei’s gene diversity (h) and Shannon index (Ι) were 0.255 3 and 0.384 1,respectively. As an endemic species whose distribution is very limited,ssp.wolongensis has high genetic diversity compared to ssp.sinensis. At population level,high genetic variation was also detected:total means of three parameters (PPB,h and I) were 63.42%,0.219 3 and 0.328 7,respectively. The Gst showed 14.25% genetic variation among populations,which indicated most of the variation existed mainly within populations. The results of AMOVA showed 19.18% differentiation among populations. These results were in consistent with the characters that H.rhamnoides L.ssp.wolongensis is an outcrossing,wind-pollinated plant.