RAPD analysis of genetic diversity of Kobresia humilis along the eastern of QinghaiTibet Plateau of China
青藏高原东部矮生嵩草遗传多样性的RAPD研究

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 Gst-values (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).