背景:白羽扇豆(LupinusalbusL.)是一种高蛋白的旧世界谷物豆类,具有显着的食品和饲料生产兴趣。它播种在秋天或早春,取决于当地的农业气候条件。本研究旨在鉴定与春化反应性相关的等位基因变异,为了提高我们对豆科植物开花调节途径的认识,并根据当前育种和适应气候变化的需要,开发用于所需物候的分子选择工具。
结果:大约120种白羽扇豆来自欧洲的各种环境,非洲,和亚洲在三种不同春化强度的环境中在野外条件下进行了表型分析,即,一个地中海和意大利的一个次大陆气候地点正在秋季播种,和法国春季播种的次生气候地点。从中提取的262个个体基因型在长时间光周期的温室中进行了表型分析,而无需进行春化。物候数据,以及通过多样性阵列技术测序(DArT-seq)和基于PCR的筛选方法产生的标记数据,这些标记数据针对连锁图谱中已发表的数量性状基因座(QTL)和新鉴定的FLOWERINGLOCUST同源物启动子区域的插入/缺失多态性,LalbFTc1基因(Lalb_Chr14g0364281),进行了全基因组关联研究(GWAS)。种群结构遵循物候和隔离的差异。GWAS突出显示了许多与开花时间显着相关的基因座,包括四个LalbFTc1基因启动子缺失:2388bp和2126bp在5'端缺失,启动子中部有264bp缺失,启动子3'末端有28bp缺失。除了LalbFTc1删除,这组包含DArT-seq标记,这些标记与先前发表的Lalb_Chr02,Lalb_Chr13和Lalb_Chr16染色体中的主要QTL以及其他染色体中新发现的QTL相匹配。
结论:这项研究强调了开花时间的新型QTL,并验证了已经发表的QTL,从而为旧世界羽扇豆物种中FTc1基因功能进化向春化途径的趋同提供了新证据。此外,这项研究提供了一组特异于极端表型(最早或最新)的基因座,等待在春季或冬季播种的标记辅助选择中进一步实施.
BACKGROUND: White lupin (Lupinus albus L.) is a high-protein Old World grain legume with remarkable food and feed production interest. It is sown in autumn or early spring, depending on the local agroclimatic conditions. This study aimed to identify allelic variants associated with
vernalization responsiveness, in order to improve our knowledge of legume flowering regulatory pathways and develop molecular selection tools for the desired phenology as required for current breeding and adaptation to the changing climate.
RESULTS: Some 120 white lupin accessions originating from a wide range of environments of Europe, Africa, and Asia were phenotyped under field conditions in three environments with different intensities of
vernalization, namely, a Mediterranean and a subcontinental climate sites of Italy under autumn sowing, and a suboceanic climate site of France under spring sowing. Two hundred sixty-two individual genotypes extracted from them were phenotyped in a greenhouse under long-day photoperiod without
vernalization. Phenology data, and marker data generated by Diversity Arrays Technology sequencing (DArT-seq) and by PCR-based screening targeting published quantitative trait loci (QTLs) from linkage map and newly identified insertion/deletion polymorphisms in the promoter region of the FLOWERING LOCUS T homolog, LalbFTc1 gene (Lalb_Chr14g0364281), were subjected to a genome-wide association study (GWAS). Population structure followed differences in phenology and isolation by distance pattern. The GWAS highlighted numerous loci significantly associated with flowering time, including four LalbFTc1 gene promoter deletions: 2388 bp and 2126 bp deletions at the 5\' end, a 264 bp deletion in the middle and a 28 bp deletion at the 3\' end of the promoter. Besides LalbFTc1 deletions, this set contained DArT-seq markers that matched previously published major QTLs in chromosomes Lalb_Chr02, Lalb_Chr13 and Lalb_Chr16, and newly discovered QTLs in other chromosomes.
CONCLUSIONS: This study highlighted novel QTLs for flowering time and validated those already published, thereby providing novel evidence on the convergence of FTc1 gene functional evolution into the
vernalization pathway in Old World lupin species. Moreover, this research provided the set of loci specific for extreme phenotypes (the earliest or the latest) awaiting further implementation in marker-assisted selection for spring- or winter sowing.