湖北省十堰地区野生板栗cpSSR遗传多样性研究

为了明确神农架地区野生板栗资源遗传背景,选用4对呈现多态性的叶绿体微卫星引物,对湖北省十堰辖区内野生板栗进行了遗传结构和叶绿体单倍型分析。结果表明4个位点在4个居群的53个样本中扩增出10个等位基因。等位基因数(A)平均为2.5,有效等位基因数(Ne)平均为1.696,PIC值平均为0.312,各遗传参数值远低于核基因组对群体研究的相应值。4个等位基因从53个样本中共给出5种单倍型,既有共享率超过66%的单倍型,在房县居群中也存在稀有单倍型,其中丹江口和房县板栗天然野生居群,具有较高的单倍型多样性,杂合度分别为0.4062和0.3794,明显高于其他地区,显示两地是板栗的分布及遗传多样性中心。基于cpSSR数据,对板栗地方品种与天然野生居群间的遗传结构、关系及地方品种的起源进行了初步探讨。AMOVA分析显示,83%的cpSSR变异存在于居群之间,17%来自居群内。研究表明,十堰地区野生板栗具有较高的多样性,叶绿体单倍型分析更能直观的表现野生板栗的区域分布规律。

Diversity of wild chestnut chloroplast DNA SSRs in Shiyan

In order to study the genetic background of the wild Chinese chestnut resources in Shennongjia,four pairs of chloroplast simple-sequence repeats(cpSSRs) were used to investigate the population genetic structure and the distribution of chloroplast haplotypic variation in the wild populations of Chinese chestnuts collected from Shiyan prefecture of Hubei province.Four cpSSR presented 10 variations in the tested plants.Average number of alleles(A) and effective number of alleles(Ne) were 2.5 and 1.696,respectively.Average PIC was 0.312.Five haplotypes were found among the 53 tested individuals.66% of all the individuals shared the same haplotype,while one sample in the Fangxian population showed a specific haplotype.With 0.4026 and 0.3794 of heterozygosity,the Danjiangkou and Fangxian populations showed a relatively higher haplotype diversity than other two.AMOVA analysis showed that 83% of the total cpSSR variation was attributable to differences among populations,and 17% to differences within populations.The results indicated that high diversity of the wild C.mollissima in Shiyan prefecture existed and cpSSR haplotype analysis would be useful for identifying the regional distribution of wild Chinese chestnut.