利用形态性状以及SSR标记鉴定4个川西北老芒麦品种（系）

基于23个形态性状和SSR分子标记,对在川西北推广应用的老芒麦(Elymus sibiricus)3个国审品种(‘川草2号’、‘阿坝’和‘康巴’)及1个新品系(‘雅江’)进行了鉴定研究。各品种表型性状与遗传背景差异较明显。新品系‘雅江’表现出优良的农艺性状,株高、叶长、叶宽、茎粗等形态性状均值显著优于3个对照品种(P0.05)。13对多态性好、特异性强、条带清晰的SSR引物在4个品种(系)中共扩增出90条条带,其中具有多态性的条带共68条,引物多态性条带比例(PPB)、多态性信息含量(PIC)及Shannon多样性指数(H)的平均值分别为76.32%、0.309及0.451,在供试品种(系)中均表现出较高的多态性。基于形态数据的欧氏距离和基于SSR数据的遗传距离矩阵之间具有较强的相关性(r=0.696,P=0.08),表明联合形态学标记和遗传标记能很好地用于品种鉴定,并且基于形态数据以及SSR分子标记的UPGMA聚类结果基本一致。筛选出4对引物可用于供试品种鉴定,并绘制了DNA指纹图谱。新品系‘雅江’具有明显区别于其它3个主推品种的形态特征和遗传背景,这为川西北高原老芒麦主要品种的遗传关系分析及品种的知识产权保护提供了数据支撑。

Identification of four Elymus sibiricus cultivar (strains)from Northwest Plateau of Sichuan using morphological traits and SSR markers

Based on 23 morphological traits and SSR markers,three cultivars (Chuancao No.2,Aba and Kang-ba)and a new strain (Yaj iang)of Elymus sibiricus widely utilized in Northwest Plateau of Sichuan were identi-fied.There was obvious difference among varieties at phenotypic traits and genetic background.Morphological traits were measured,includingplant height,leaf length,leaf width,Culm diameter and so on,the new strain‘Yajiang’had betterperformance in major agronomictraits than that of other three varieties (P<0.05).Fur-thermore,13 screened pairs of SSR primerwere amplified in four cultivars (strains)and generated 90 bands,of which 68 bands were polymorphic.According to the mean of percentage of polymorphic bands (PPB=76.32%),polymorphism information content (PIC=0.309)and Shannon diversity index (H=0.451),four cul-tivars (strains)presented high polymorphism.A positive correlation (r=0.696,P=0.08)existed between Eu-clidean distance and Dice genetic distance,indicating that the combination of morphological traits and genetic markers could be used for cultivar identification.Two UPGMA dendrogram based on morphological and SSR data were similar and there were differences among all cultivars (strains)for phenotypic and genetic back-ground.Furthermore,four pairs of primers (Elw0669s043,Xgwm190,WMS169 and Xgwm311)were selected for DNA fingerprinting construction and cultivar identification.In general,the present study demonstrated that the new strain‘Yajiang’was significantly different from other three E.sibiricus cultivars,and provided impor-tant data for genetic relationship analysis and intellectual property rights protection for cultivars in the North-west Plateau of Sichuan.