Seasonality control of barley flowering: from the lab to the field

开花期是大麦的一个关键的发育转变，因为植物停止生叶，并将资源分配给生殖。生物钟是一个季节大麦何时开花的关键决定因素。时钟基因PPD-H1与大麦的春季行为有关，我们还发现了另一个名为EAM8的时钟基因，它可以进一步“迁移”大麦。在伊比利亚半岛等干旱地区，利用温和的冬季条件在冬季之前播种大麦是有利的，从而获得更高的产量和更好的适合度。冬季大麦是祖先的遗传状态，在越冬之前在秋季发芽，使春化过程能够触发对开花潜力的接受。然后开花随着春季光周期的推进而发生。在有春化要求的遗传背景下评估大麦开花是学术和育种前的兴趣，但振荡器已经被调整到适当的时间开花到给定的农业气候带。为此，约克和先正达的合作伙伴在冬季大麦中构建了时钟突变。这些将在受控的气候室、温室环境和英国和欧洲大陆周围的多个田间地点进行评估，以确定抽穗期和开花时间。生殖干细胞(花分生组织)中的基因表达谱和变化将被成像。结合植物形态的生物测量，包括分蘖和许多种子产量性状，将在这些品系中评估和量化谷物特性，以另外将受控和田间环境中的开花时间与具有商业意义的产品联系起来。了解植物对其生长季节的反应具有深远的学术意义。冬大麦开花时间网络的分子遗传学尚不清楚，我们为这项工作产生的时钟等位基因是评估这一分子遗传网络的高级遗传状态。

Flowering time is a critical developmental transition in barley, as the plant stops making leaves and allocates resources to reproduction. The circadian clock is a key determinant for when in a season barley flowers. The clock gene Ppd-H1 is associated with the spring behaviour and we have identified another clock gene termed EAM8 that further "migrates" barley. In arid conditions such as the Iberian peninsula, it is advantageous for barley to be sown before winter to leverage mild winter conditions, resulting in higher yield and increased fitness. Winter barley is the ancestral genetic state, and germinates in autumn before overwintering, enabling the process of vernalisation to trigger receptiveness for the potential to flower. Flowering then occurs with the advancing photoperiods in the spring.There is an academic and pre-breeding interest to appraise barley flowering in a genetic context where there are vernalisation requirements, but where the oscillator has been tuned to appropriately time flowering to a given agro-climatic zone. For this the York and Syngenta partners have constructed clock mutations in winter barley. These would be assessed under controlled climate chambers, greenhouse settings and multiple field sites in the UK and around continental Europe for heading date and flowering time. Gene-expression profiles and changes in the reproductive stem-cells (the floral meristem) would be imaged. Coupled to biometry of plant form, including tillering and numerous seed-yield traits, grain characteristics would be assessed and quantified in these lines to additionally relate flowering time in controlled and field setting to products of commercial relevance.It is of profound academic interest to understand how a plant responds to its growing season. The molecular genetics of the flowering-time network in winter barley is not known, and the clock alleles we generated for this work are advanced genetic states to evaluate this molecular-genetic network.