鸭茅品种的SCoT遗传变异分析

Analysis of genetic diversity in a cocksfoot( Dactylis glomerata) variety using SCoT markers

本研究应用SCoT标记对32个鸭茅品种(包括国内栽培驯化品种和国外引进品种)进行研究,为揭示鸭茅栽培驯化品种与引进品种间的遗传变异差异和鸭茅新品种选育提供理论依据。研究结果表明,1)从80个SCoT引物中筛选出22个条带清晰且稳定的引物,共扩增出308条谱带,其中,多态性谱带245条,多态性比率(PPB)为79.55%,平均每个引物扩增多态性条带数为11.14条;2)栽培驯化品种平均遗传距离为0.1242,引进品种平均遗传距离为0.1952,且引进品种在多态性条带(NPB),多态性比率(PPB),基因多样性指数(H),Shannon指数(I)等水平都高于栽培驯化品种,表明栽培驯化品种的遗传多样性水平低于引进品种;3)AMOVA显示存在于栽培驯化品种和引进品种两类群之间和之内的遗传变异分别为16.32%和83.68%,更多的遗传变异存在于类群内;4)UPGMA聚类分析和主成分分析(PCA)结果表明,供试32个鸭茅品种主要聚为6大类,国内栽培驯化品种聚为类群I,国外引进品种分别聚为其他几个类群。

Start codon targeted polymorphism （SCoT） was used to analysis 32 cocksfoot （Dactylis glomerata） varieties （including cultivated and introduced varieties）,to reveal the differences of genetic diversity in cultivated and introduced varieties and to provide a theoretical basis for breeding new varieties of cocksfoot.1） Twenty-two primers were selected from 80 SCoT primers,and a total of 308 bands were amplified,of which 245 （79.55％） were polymorphic：the average was 11.14 per primer.2） The average genetic distance of cultivated varieties was 0.1242 while that of introduced varieties was 0.1952.The introduced varieties had higher genetic distances than the cultivated ones at the level of polymorphism bands （NPB） and percentage of polymorphic bands （PPB）.The gene diversity index （H） and Shannon index （Ⅰ）,indicated that the genetic diversity of cultivated varieties was lower than that of introduced varieties.3） AMOVA analysis showed that the genetic variance within and between cultivated and introduced varieties was 83.68％ and 16.32％,respectively and the main genetic variance was in the internal group.4） The results of UPGMA clustering and PCoA analysis showed that the 32 cocksfoot varieties could be divided into six groups,the cultivated varieties were in group Ⅰ while the introduced varieties were in the other five groups.