Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Agricultural College of Yangzhou University, Yangzhou, P.R. China.
Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou, P.R. China.
J Exp Bot. 2021 Sep 30;72(18):6291-6304. doi: 10.1093/jxb/erab286.
Understanding the adaptive changes in maize kernels under high-temperature stress during grain formation stage is critical for developing strategies to alleviate the negative effects on yield and quality. In this study, we subjected waxy maize (Zea mays L. sinensis Kulesh) to four different temperature regimes from 1-15 d after pollination (DAP), namely normal day/normal night (control), hot day/normal night, normal day/hot night, and hot day/hot night. Compared to the control, the three high-temperature treatments inhibited kernel development and starch deposition. To understand how the kernels responded to high-temperature stress, their transcriptomes, proteomes, and metabolomes were studied at 10 DAP and 25 DAP. This showed that genes and proteins related to kernel development and starch deposition were up- and down-regulated, respectively, at 10 DAP, but this pattern was reversed at 25 DAP. Metabolome profiling under high-temperature stress showed that the accumulation patterns of metabolites at 10 DAP and 25 DAP were inversely related. Our multiomics analyses indicated that the response to high-temperature stress of signaling pathways mediated by auxin, abscisic acid, and salicylic acid was more active at 10 DAP than at 25 DAP. These results confirmed that high-temperature stress during early kernel development has a carry-over effect on later development. Taken together, our multiomics profiles of developing kernels under high-temperature stress provide insights into the processes that underlie maize yield and quality under high-temperature conditions.
了解玉米灌浆期高温胁迫下籽粒的适应性变化对于开发减轻产量和品质下降负面影响的策略至关重要。本研究在授粉后 1-15 天（DAP）期间，对糯玉米（Zea mays L. sinensis Kulesh）分别进行了四个不同的温度处理，即正常日/正常夜（对照）、热日/正常夜、正常日/热夜和热日/热夜。与对照相比，三种高温处理均抑制了籽粒发育和淀粉积累。为了了解籽粒对高温胁迫的响应机制，在 10 DAP 和 25 DAP 时研究了它们的转录组、蛋白质组和代谢组。结果表明，在 10 DAP 时，与籽粒发育和淀粉积累相关的基因和蛋白分别上调和下调，但在 25 DAP 时则相反。高温胁迫下的代谢组谱分析表明，10 DAP 和 25 DAP 时代谢物的积累模式呈反向关系。我们的多组学分析表明，高温胁迫下由生长素、脱落酸和水杨酸介导的信号通路的响应在 10 DAP 时比在 25 DAP 时更为活跃。这些结果证实了早期籽粒发育过程中的高温胁迫对后期发育有延续效应。总之，我们对高温胁迫下发育中籽粒的多组学图谱研究为了解高温条件下玉米产量和品质的形成过程提供了新的认识。
