Testing a cytokinin dilution model of floral duration in barley

植物开花产生的种子和果实提供了人类社会消耗的绝大部分卡路里。植物试图通过正确地选择开花的起始时间和持续时间来优化它们的繁殖成功率，从而在当前的环境条件下产生“正确”数量的种子。谷类作物，包括主要的英国作物大麦，开花的持续时间决定了开花的数量，以及作物的“产量潜力”。利用模式植物拟南芥，我们最近发现植物激素细胞分裂素的浓度决定了拟南芥开花的时间。随着细胞分裂素在越来越大的茎系统中被稀释，植物停止生产和开花，导致开花结束。根据初步的证据，我们认为这种机制也可以调节谷类作物的开花时间，从而调节产量潜力。我们假设，增加谷物中细胞分裂素的敏感性将因此增加开花时间和产量潜力。在本提案中，我们的目标是使用高分辨率表型，先进的生物成像，转录组学以及经典和分子遗传学的组合来验证这一假设。了解控制花期的机制将使我们能够挑战当前作物产量的限制，并及时改变大麦和其他主要谷类作物的产量潜力。这将有助于满足生产更多粮食以养活不断增长的全球人口的迫切需要。

The seeds and fruit produced by flowering in plants provides the vast majority of calories consumed by human societies. Plants attempt to optimize their reproductive success by correctly timing the initiation and duration of flowering, to produce the 'correct' number of seed for prevailing environmental conditions. In cereal crops, including the key UK crop barley, the duration of flowering determines the number of flowers formed, and the 'yield potential' of the crop. Using the model plant Arabidopsis thaliana, we have recently shown that the concentration of the plant hormone cytokinin determines how long Arabidopsis flowers for. As cytokinin becomes diluted across the increasingly large shoot system, plants stop producing and opening flowers, leading to the end of flowering. Based on preliminary evidence, we believe that this same mechanism also regulates duration of flowering - and hence yield potential - in cereal crops. We hypothesise that increasing cytokinin sensitivity in cereals will therefore increase the duration of flowering and their yield potential. In this proposal, we aim to test this hypothesis using a combination of high-resolution phenotyping, advanced bioimaging, transcriptomics and classical and molecular genetics. Understanding the mechanisms controlling flowering duration will allow us to challenge current limitations on crop yields, and drive a timely change in yield potential in barley and other key cereal crops. This will help to meet the pressing need to produce more food to feed the growing global population.