摘要
基于随机扩增多态DNA(RAPD)方法分析了青藏高原东部矮生嵩草(Kobresiahumilis)8个居群的遗传多样性及分化程度。14条随机引物共扩增出194个位点数,其中多态性片段168个。研究表明,矮生嵩草无论是在物种水平(多态条带比率PPB(%)为86·60%,Nei’s基因多样性(h)为0·2622,Shannon’s信息指数(I)为0·3983),还是在居群水平(PPB=62·65%,h=0·2126,I=0·3185),都具有较高的遗传多样性,居群的遗传多样性大小与生境有相关性。而且,用SPSS分析得出,8个居群的遗传多样性大小与海拔没有明显相关性。用AMOVA数据表明矮生嵩草的遗传变异主要分布在居群内(83·04%),居群间变异较小(16·96%)。遗传分化指数Gst也显示了相似的结果(0·1891)。从矮生嵩草8个居群的遗传距离和聚类分析发现,以及用NTSYS对矮生嵩草8个居群的的遗传距离矩阵与地理距离矩阵间的关系进行Mantel检测,其结果表明各居群间的遗传距离与地理距离之间没有明显相关性(r=0·37779,p=0·9718>0·05)。
Kobresia humilis is a very important fine pasture and ecological grass in the Qinghai-Tibet Platau. In present study, the genetic diversity of K. humilis collected from eastern of the Qinghai-Tibet plateau in China, were investigated using RAPD markers. 194 loci were identified with 14 oligonucleotide primers, out of which 168 loci were polymorphic. K. humilis showed high genetic diversity： The percentage polymorphic loci （PPB%） was 86.60%, Nei＇s gene diversity （h） was 0.2622 and Shannon＇s information index （I） was 0.3983 at the species level; while the PPB% was 62.65%, h was 0.2126 and I was 0.3185, at the level of population. Moreover, the results showed that there was a relationship between the habitats and genetic diversity of K. humilis, but no correlation between the altitude and genetic diversity. AMOVA showed that most of the genetic variability （83.04%） resided among individuals within populations, whereas only 16.96% resided among populations. The Gstvalues （0. 1891） showed the similar result. Additionally, Nei＇s unbiased genetic distance matrix compared with a corresponding geographic distance matrix showed the two matrices were not significantly correlated （ r = 0.37779,p = 0.9718 〉 0.05）.
出处
《生态学报》
CAS
CSCD
北大核心
2006年第8期2494-2501,共8页
Acta Ecologica Sinica
基金
兰州大学干旱农业生态教育部重点实验室基金资助项目~~
