Winter warming post floral initiation delays flowering via bud dormancy activation and affects yield in a winter annual crop

背景回顾：Winter annual life history is conferred by the requirement for vernalization to promote the floral transition and control the timing of flowering. 

主要发现：Here we show using winter oilseed rape that flowering time is controlled by inflorescence bud dormancy in addition to vernalization. 

结果1-突变体库筛选：Winter warming treatments given to plants in the laboratory and field increase flower bud abscisic acid levels and delay flowering in spring. 

结果2-pdx1.1突变及拯救：We show that the promotive effect of chilling reproductive tissues on flowering time is associated with the activity of two FLC genes specifically silenced in response to winter temperatures in developing inflorescences, coupled with activation of a BRANCHED1-dependent bud dormancy transcriptional module. 

结果3-非磷酸化维生素B6：We show that adequate winter chilling is required for normal inflorescence development and high yields in addition to the control of flowering time. 

结论：Because warming during winter flower development is associated with yield losses at the landscape scale, our work suggests that bud dormancy activation may be important for effects of climate change on winter arable crop yields.

Winter warming during flower bud development delays flowering and is associated with yield reductions.

 摘 要 

年度冬季生活史是植物春化所必需经历的条件，促进成花转变并控制开花时间。本文中，作者发现冬油菜的开花时间除了受到春化作用控制外，还会受到花芽休眠的影响。在冬季，无论是在实验室还是在大田条件下，使用暖温处理冬油菜会增加其花芽中的ABA含量，并导致其在春季的开花时间延迟。作者发现低温对于开花时间的促进作用与两个FLC基因的活性相关，这两个FLC基因在发育中的花序组织中会响应于冬季低温，从而特异性沉默，同时该过程会伴随着一个依赖于BRANCHED1的芽休眠转录模块的激活。作者发现除了对开花时间的控制，充分的冬季低温对于维持正常的花序发育及高产都是必须的。因为在宏观尺度上，冬季花发育过程中遭遇暖温常常与来年的产量损失有关，因此本文的工作揭示了芽休眠激活可能对于气候变化影响冬季耕作作物产量是十分重要的。

doi: https://doi.org/10.1073/pnas.2204355119