邓氏马先蒿遗传多样性的ISSR分析

ISSR Analysis for Genetic Diversity of Pedicularis dunniana

运用ISSR-PCR分子标记技术对邓氏马先蒿(Pedicularis dunniana)云南中甸以及四川木格措两个自然居群的遗传分化以及遗传多样性进行研究。结果表明:物种水平上邓氏马先蒿遗传多样性水平较高(PPB=62%),但居群平均水平很低,云南中甸居群多态性位点百分率只有23%。四川居群也仅仅是27%,AMOVA分析结果表明,居群间基因分化系数Fst=0.7462,即遗传变异绝大部分来源于两居群间,居群间表现出强烈的遗传分化。自交的交配方式以及小居群产生的遗传漂变效可能是造成邓氏马先蒿目前遗传结构的主要原因。

ISSR markers was used to measure genetic diversity and genetic structure of the 40 individuals from two natural populations of Pedicularis dunniana ,one autogamous perennial herb. A total of 100 DNA fragments were scored from 8 ISSR primers, of which 62% were polymorphic. A low level of genetic diversity within populations was detected （PPB = 27%, 23%, respectively）. An analysis of Molecular Variance （AMOVA） was used to apportion the variation within and among populations. Results indicated that most of the variation （74.62%） resided among the populations, while only a small amount of variation （25.38%） within the populations. Selfing is likely the factor resulting in the low level of genetic diversity within the populations. Genetic drift in small populations and probably founder effects might also be the most important reasons that may explain the current genetic structure of P. dunniana.