Molecular, genetic and phenotypic analysis of an early-heading mutant in diploid einkorn wheat

在谷物育种中，对特定环境的最佳适应以及随后的高产潜力主要取决于开花时间。然而，开花时间通常受到三个决定因素之间复杂的相互作用的影响：光周期和春化需求以及栽培/基因型的内在开花能力。提早开花的内在能力也被称为“提早本身”。本研究对二倍体小麦（T. monococum L.）系KT3-5的早抽穗突变体进行了研究，该突变体在3A染色体长臂的极远端具有一个主隐性早性（eps）位点。在该项目中，我们将(i)对二倍体小麦早穗突变体KT3-5进行详细的表型分析和高分辨率遗传图谱绘制，（ii）鉴定和分离影响早穗发育、控制开花时间和小穗数的新型草特异性基因/蛋白，以及（iii）研究候选基因在早穗发育过程中的表达模式、组织特异性和功能。通过对小麦及相关禾草抽穗时间和颖花数的发育遗传过程的进一步了解，对小粒谷物作物开花时间的精细调控具有重要意义。

In cereal breeding, optimal adaptation to a given environment and subsequently high yield potential is mainly determined by the time of flowering. Time to flowering, however, is commonly affected by a complex interplay between three determinants: photoperiodic and vernalization requirements as well as the intrinsic capability of a cultivar/genotype to flower. The intrinsic capability to flower early is also called ‚earliness per se’. Here we would like to investigate an earlyheading mutant from diploid einkorn wheat (T. monococcum L.), line KT3-5, which possesses a single major recessive earliness per se (eps) locus on the very distal end of the long arm of chromosome 3A. During the proposed project we will (i) perform detailed phenotypic analyses and high-resolution genetic mapping of the early-heading mutant KT3-5 in diploid einkorn wheat, (ii) identify and isolate novel grass-specific genes/proteins which affect early spike development, controlling flowering time and spikelet number, and (iii) study the expression pattern, tissue-specificity and function of candidate gene(s) during early spike development. The molecular isolation of genes involved in early spike development will make an important contribution to future fine-tuning of flowering time in small grain cereal crops by providing a better understanding of the developmental genetic processes underlying heading time and spikelet number in wheat and related grasses.