Heading date is a crucial agronomic trait. However, rice usually delays heading due to the photoperiod, temperature, hormones or age. The present research was conducted to analyze the mechanism controlling heading date in F₁ hybrid rice. We constructed two test-crossing populations using two introgression lines (ILs), P20 and P21 coming from SH527/FH838 as the male parent, respectively, and male sterile line Jin23A as the female parent. Meanwhile, the F₁ hybrids of H20, obtained by mating P20 with Jin23A and having no heading, and H21, from the crossing between P21 and Jin23A having normal heading, were both observed under long days. Here, we analyzed the photoperiodic response of F₁ hybrids by transcriptome and metabolome profiling. The greater differences displayed in the transcriptome and the metabolome were caused by photoperiod (exogenous) instead of genes (endogenous). The coping mechanism resulted from long days (LD) in H20, leading to differences in the circadian rhythm and glutathione metabolism relative to other samples. The circadian oscillator and GSH/GSSG cycle typically regulate ROS homeostasis, and both of them are responsible for modulating ROS in H20 under LD condition. Both circadian rhythm genes and the reported genes related to heading date function via the DHD1/OsMFT1-Ehd1-RFT1-OsMADS14/OsMADS18 pathway and the glutathione metabolism pathway by regulating oxidative reduction processes. Both pathways are involved in the heading process and they interacted through the oxidative reduction process which was induced by photoperiod regulation, and all of them collectively modulated the heading process. The results of this study will be helpful for unraveling the mechanism of F₁ hybrid responses to unheading under LD condition.

抽穗期是关键的农艺性状。但是，大米通常会因光周期，温度，激素或年龄而延迟抽穗。本研究旨在分析控制F ₁杂交水稻抽穗期的机理。我们使用来自SH527 / FH838的两个渗入系（IL）P20和P21分别作为雄性亲本和雄性不育系Jin23A作为雌性亲本构建了两个测交种群。同时，在较长的日子里，观察到通过将P20与Jin23A交配而没有抽穗的H20的F ₁杂种和从P21和具有正常抽穗的Jin23A之间的杂交得到的H21。在这里，我们分析了F ₁的光周期响应转录组和代谢组谱分析显示杂种。转录组和代谢组中显示的更大差异是由光周期（外源）而不是基因（内源）引起的。应对机制是由H20的长日（LD）引起的，导致相对于其他样品的昼夜节律和谷胱甘肽代谢差异。昼夜节律振荡器和GSH / GSSG周期通常调节ROS稳态，并且两者都在LD条件下调节H20中的ROS。有关抽穗期功能无论昼夜节律基因和基因报告通过的DHD1 / OsMFT1-EHD1-RFT1-OsMADS14 / OsMADS18途径和谷胱甘肽代谢途径通过调节氧化还原过程。两种途径都参与抽穗过程，它们通过光周期调节诱导的氧化还原过程相互作用，并且所有这些通道共同调节了抽穗过程。这项研究的结果将有助于阐明LD条件下F ₁杂种对去航向的反应机制。