Genetic and developmental analysis of pre-anthesis phases in barley (Hordeum vulgare L.)

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。在发育上，开花（或花前发育）可分为三个阶段：叶片形成（LI）阶段、小穗形成（SI）阶段和小穗生长期（SG）阶段。每个阶段的长度可以根据环境条件（温度和光周期）而变化，并独立地影响最终开花时间和随后的产量。在该项目中，我们将(i)对212种春大麦（Hordeum vulgare L.）基因型进行详细的表型分析，以了解其花前发育中LI、SI和SG期长度的差异，（ii）利用全基因组标记-性状关联来鉴定单个花前期长度的QTL，以及（iii）利用大麦、水稻、高粱、以及短柄藓基因组序列，用于在212个大麦基因型中进行各期QTL推断候选基因的定位和测序。这将是第一个与大麦或其他谷类作物开花前发育相关的关联/QTL研究。通过更好地了解大麦和其他禾草抽穗时间的发育遗传过程，参与早期穗发育的QTL/基因将对未来小粒谷物作物开花时间的微调做出重要贡献。

In cereal breeding, optimal adaptation to a given environment and subsequently high yield potential is mainly determined by the time of flowering. Developmentally, time to flowering (or pre-anthesis development) can be divided into three phases: the leaf initiation (LI) phase, the spikelet initiation (SI) phase, and the spikelet growth (SG) phase. The length of each phase can vary depending on environmental conditions (temperature and photoperiod) and contributes independently towards final time to flowering and subsequently yield. During the proposed project we will (i) perform detailed phenotypic analyses of 212 spring barley (Hordeum vulgare L.) genotypes for differences in their pre-anthesis development regarding length of the LI, SI and SG phases, (ii) use genome-wide marker-trait associations for the identification of QTL for the length of individual pre-anthesis phases, and (iii) utilize collinearity between barley, rice, Sorghum, and Brachypodium genomic sequences for mapping and sequencing of deduced candidate genes underlying QTL for individual phases in 212 barley genotypes. This would be the first association/QTL study related to the pre-anthesis development in barley or any other cereal crop. QTL/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 in barley and other grasses.