【摘要】 采用野外形态调查和DNA分子标记方法,对内蒙古高原7个不同地理分布的克氏针茅种群进行研究,结果表明:不同地理分布区克氏针茅种群的表型性状受环境影响改变程度的差异不同,其中营养枝高度、生殖枝高度、千粒重、颖果长、芒柱长具有随降水量递减而变小、变短的趋势;而颖果直径表现为随降水量的递减逐渐增加的趋势。随机扩增多态DNA(RAPD)分析表明,16个有效引物共扩增出129个位点,其中多态位点128个(99.22%)。AMOVA分析显示,克氏针茅种群64.95%的遗传变异发生在种群内,35.05%的遗传变异发生在种群间。种群遗传多样性与其所处生境的年均温呈显著相关关系(r=0.802,t=3.003>t0.05=2.571)。聚类分析表明,7个种群一级聚类分为4个分支,有相似生态条件的种群具有优先聚类的趋势,种群间遗传距离与地理距离无明显的相关性。克氏针茅有较大的形态变化和丰富的遗传多样性,环境适应潜力大,可作为西部地区植被恢复及草地生态建设的首选植物之一。更多还原

【Abstract】 Based on field investigation of morphological characteristics and DNA molecular markers technology,seven S.krylovii populations in different geographical conditions in Inner Mongolia were studied.The results showed that: variation degrees of morphological traits of seven S.krylovii populations were different in corresponding to different environmental conditions.Reproductive tiller length,vegetative tiller length,thousand kernel weight,caryopsis length and awn length got shorter and smaller following the decreasing precipitation,however,caryopsis diameter increased little by little following the decreasing precipitation.It demonstrated that 129 loci were amplified with 16 effective primers,including 128 polymorphic loci which was 99.22% in total by random amplified polymorphic DNA(RAPD) technology.35.05% of genetic variation was in inter-populations and 64.95% had been found among populations by AMOVA analysis.The genetic diversification of population was correlated with annual average temperate(r=0.802,t=3.003>t0.05=2.571),however,the genetic distance among populations was not correlated with geography distance.S.krylovii was treated as a kind of preferred grass in revegetation and grassland ecological construction because of bigger morphological changes,abundant genetic diversity and stronger environment adaptation.更多还原