摘要
采用48个SSR标记分析了海南11个普通野生稻自然居群的遗传多样性。结果显示海南普通野生稻自然居群具有较丰富的遗传变异(Na=8.3,He=0.716)。居群内多数等位基因(77.6%)频率较低,其中,70个等位基因仅出现在1个居群中。62.9%的等位基因显著偏离哈迪-温伯格平衡,多数居群及等位基因实际杂合度大于期望杂合度,表明居群内自交率低、杂合体过剩。居群间遗传变异差异明显,在11个自然居群中,崖城居群遗传多样性最低(Na=1.7,He=0.348),和庆、椰林B两居群遗传变异最为丰富(和庆:Na=4.0,He=0.577;椰林B:Na=4.0,He=0.531)。Mantel测验表明,居群间Nei遗传距离与地理距离呈极显著相关(r=0.386,P=0.004)。东、西海岸居群间遗传分化显著但较小(Fst=0.048,P=0.024),而居群间遗传分化则较大(Fst=0.335,P<0.001)。11个自然居群间基因流非常有限(Nm=0.404),表明居群间隔离程度较大。基于居群等位基因数目、基因多样性指数以及基因频率特点,认为海南11个自然居群中和庆和椰林B居群应是优先保护对象。
A set of 48 SSR markers was used to assess the genetic diversity in 11 natural populations of common wild rice （Oryza rufipogon Grill. ） from Hainan Province, China. The results showed that the genetic variability of the common wild rice in Hainan is relatively high （Na = 8.3, He=0.716）. Seventy alleles （17.6%） were found in only one of the 11 populations and a large number of alleles （77.60% ） were at low frequency. For most SSR loci and populations, expected heterozygosities （Nei＇s He） under Hardy-Weinberg equilibrium were apparently lower than the observed heterozygosities, indicating a considerable excess of heterozygotes within populations. Genetic variation among populations varied widely, ranging from the lowest diversity values in Yacheng population （ Na = 1.7, He = 0. 348） to maximal diversity in Heqing （ Na = 4. 0, He = 0. 577） and Yelin-B （Na= 4. O, He=0. 531） populations. A Mantel test revealed that the pairwise Nei＇s genetic distance between populations was significantly correlated with geographical distance （r=0. 386, P=0. 004）. Genetic differentiation was weak but significant between populations of East and West Coast regions（Fst=0.048, P=0.024）. Of the total differentiation among populations, 33.30.% was explained by divergence among populations within a region, meaning most of the genetic diversity was due to differences within populations. A mean Nm value of 0.404 suggested a limited gene flow among the assayed populations. Based on the results in genetic diversity and allele frequency analysis, it was suggested that populations both in Heqing and Yelin-B should be given conservation priority.
出处
《中国水稻科学》
CAS
CSCD
北大核心
2007年第6期573-578,共6页
Chinese Journal of Rice Science
基金
国家973计划资助项目(2004CB117201)
中央级公益性科研院所专项资金项目(100006)
农业部农业野生植物保护专项资助项目
浙江省重点科研国际合作项目(2006C24012)
关键词
普通野生稻
微卫星标记
遗传多样性
分子方差分析
Oryza rufipogon
simple sequence repeat
genetic diversity
analysis of molecular variance
