Molecular Breeding:中科院成都生物所陈静副研究组发表大麦品种适应

摘要 : 近日国际权威刊物Molecular Breeding 上发表中国科学院成都生物所陈静副研究组发表的对大麦品种适应性分子调控机制研究文章。

近日国际权威刊物molecular Breeding 上发表中国科学院成都生物所陈静副研究组发表的对大麦品种适应性分子调控机制研究文章。

开花是高等植物生命周期中的重要环节。开花时间是一个受遗传因子和环境因素协同调控的复杂性状，春化作用、光周期反应以及固有的早熟性是调控植物由营养生长向生殖生长转换的重要遗传系统。对于小麦、大麦等禾本科作物，在种子萌发后到营养生长的苗期必须经过低温诱导才能正常开花结实， 这一过程称为春化作用(Vernalization)。春化阶段是作物对不同气候条件适应性具有决定作用的重要发育阶段,根据其对温度高低和时间长短的不同要求, 品种分为春性和冬性两大类型。品种的春化特性是决定其环境适应性和种植分布范围的关键因素。

大麦对春化的要求主要受春化基因HvVRN1和HvVRN2抑制因子的互作调控。中国科学院成都生物研究所西南特色作物资源生物学学科组的张赤红博士、陈静副研究员等，对中国大麦HvVRN1基因突变机制、单倍型分类、HvVRN1和HvVRN2基因等位变异及其与品种环境适应性的关系进行了研究。从373份中国大麦资源中鉴定到包含新等位基因HvVRN1-11在内的11个HvVRN1内含子I等位基因变异，而HvVRN2位点仅存在野生型(冬性)和缺失突变(春性)两种类型。进一步调查发现：(1)HvVRN1(冬性)和HvVRN1-8(春性)是中国大麦的优势等位基因;野生型HvVRN2(冬性)和HvVRN2缺失突变(春性)分别是我国冬、春大麦区的优势等位基因;(2)含有冬性HvVRN2的大麦品种中HvVRN1等位基因数目要多于含有春性HvVRN2的大麦品种;HvVRN1等位基因数目与生态区地理纬度呈极显著负相关(r= -0.938，P<0.01)，但与海拔高度没有显著关联;(3)等位基因HvVRN1-8 是春大麦品种普遍共有的遗传基础，分布于八个大麦生态区;野生型HvVRN1分布于六个大麦生态区，是MLYW和YHW冬大麦区的优势等位基因;HvVRN1-1 和HvVRN1-5分别是

IMPS和NePS生态区的优势等位基因，在其它生态区极为少见。(4)HvVRN1第一内含子是重要的功能突变热点区域，缺失区段两端的短片段重复序列暗示染色体双链断裂后进行非同源重组可能是该基因的主要突变机制;(5)结合HvVRN1第一内含子侧翼序列的多样性，将12个HvVRN1基因单倍型分为5个组，并分析了其可能的进化关系。本研究为全球气候波动背景下适应性大麦品种选育提供了理论依据和策略，基因特异性功能分子标记的开发也为分子标记辅助育种提供了重要技术手段。


基因分布图

原文链接：

Identification and distribution ofVERNALIZATION1 alleles in Chinese barley (Hordeum vulgare) germplasm

原文摘要：

VERNALIZATION1 (VRN1) is a central regulator of the vernalization requirement, which affects the yield and geographical distribution of Triticeae crops through regulation of the flowering time. The first intron (Intron I) of VRN1 contains putative cis-elements that mediate repression of VRN1expression. Allelic variations in Intron I are closely associated with increased VRN1 expression in vernalization-responsive accessions in the absence of vernalization. In this study, diagnostic molecular markers were developed to distinguish the main 12 known alleles, including a new allele, of barley (Hordeum vulgare) VRN1 (HvVRN1), and to investigate HvVRN1 alleles in 373 barley varieties from major agroecological regions in China. The new allele, HvVRN1-11, with a 3172-bp deletion in Intron I of HvVRN1, was identified in a Chinese barley landrace. Analysis of eight polymorphic sites flanking major variations in Intron I of HvVRN1 classified the 12 HvVRN1 alleles into five distinct groups. Compared with modern commercial barley, landraces possessed greater genetic diversity and contained the majority of HvVRN1 alleles, especially in the winter barley regions. HvVRN1 diversity in terms of allele number reduced significantly (P < 0.01) along with higher growing latitudes, but increased in accessions carrying the winter HvVRN2 allele. Wild-typeHvVRN1 and the HvVRN1-8 allele showed the most widespread distribution in most regions whereasHvVRN1-1 & HvVRN1-8, and HvVRN1-5 are predominant in the Inner Mongolian Plateau spring barley region and the Northeast Plain spring barley region, respectively, with relatively higher latitudes. Compared with landraces, the frequency of HvVRN1-8 decreased while wild-type HvVRN1increased significantly (P < 0.01) in commercial varieties. Our study classified HvVRN1 genetic diversity in a large collection of Chinese germplasm and provided a tool for identifying HvVRN1alleles in barley breeding populations.

DOI：10.1007/s11032-015-0346-x

作者：陈静

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