Crops with resilience to multiple climatic stresses are essential for increased yield stability. Here, we evaluate the interaction between two loci associated with flooding survival in rice (Oryza sativa L.). ANAEROBIC GERMINATION 1 (AG1), encoding TREHALOSE 6‐PHOSPHATE PHOSPHATASE 7 (TPP7), promotes mobilization of endosperm reserves to enhance the elongation of a hollow coleoptile in seeds that are seeded directly into shallow paddies. SUBMERGENCE 1 (SUB1), encoding the ethylene‐responsive transcription factor SUB1A‐1, confers tolerance to complete submergence by dampening carbohydrate catabolism, to enhance recovery upon desubmergence. Interactions between AG1/TPP7 and SUB1/SUB1A‐1 were investigated under three flooding scenarios using four near‐isogenic lines by surveying growth and survival. Pyramiding of the two loci does not negatively affect anaerobic germination or vegetative‐stage submergence tolerance. However, the pyramided AG1 SUB1 genotype displays reduced survival when seeds are planted underwater and maintained under submergence for 16 d. To better understand the roles of TPP7 and SUB1A‐1 and their interaction, temporal changes in carbohydrates and shoot transcriptomes were monitored in the four genotypes varying at the two loci at four developmental timeponts, from day 2 after seeding through day 14 of complete submergence. TPP7 enhances early coleoptile elongation, whereas SUB1A‐1 promotes precocious photoautotrophy and then restricts underwater elongation. By contrast, pyramiding of the AG1 and SUB1 slows elongation growth, the transition to photoautotrophy, and survival. mRNA‐sequencing highlights time‐dependent and genotype‐specific regulation of mRNAs associated with DNA repair, cell cycle, chromatin modification, plastid biogenesis, carbohydrate catabolism and transport, elongation growth, and other processes. These results suggest that interactions between AG1/TPP7 and SUB1/SUB1A‐1 could impact seedling establishment if paddy depth is not effectively managed after direct seeding.

中文翻译：

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洪水恢复位点“淹没 1”和“厌氧发芽 1”在水下幼苗中相互作用。


具有抵御多种气候胁迫能力的作物对于提高产量稳定性至关重要。在这里，我们评估了与水稻（ Oryza sativa L.）洪水生存相关的两个基因座之间的相互作用。厌氧发芽 1 ( AG1 ) 编码海藻糖 6-磷酸磷酸酶7 ( TPP7 )，可促进胚乳储备的动员，从而提高直接播种到浅稻田的种子中空心胚芽鞘的伸长。 SUBMERGENCE 1 ( SUB1 ) 编码乙烯响应转录因子SUB1A-1 ，通过抑制碳水化合物分解代谢赋予对完全淹没的耐受性，以增强脱离淹没后的恢复。通过调查生长和存活率，使用四个近等基因系在三种洪水情景下研究了AG1/TPP7和SUB1/SUB1A-1之间的相互作用。两个位点的金字塔不会对厌氧发芽或营养阶段的淹没耐受性产生负面影响。然而，当种子在水下种植并在水下保持 16 天时，金字塔形AG1 SUB1基因型的存活率降低。为了更好地了解TPP7和SUB1A-1的作用及其相互作用，从播种后第 2 天到完全淹没的第 14 天，在四个发育时间点的两个基因座上不同的四种基因型中监测了碳水化合物和芽转录组的时间变化。 TPP7增强早期胚芽鞘伸长，而SUB1A-1促进早熟光能自养，然后限制水下伸长。 相比之下， AG1和SUB1的金字塔化会减缓伸长增长、向光合自养的转变以及存活。 mRNA 测序强调了与 DNA 修复、细胞周期、染色质修饰、质体生物发生、碳水化合物分解代谢和运输、伸长生长和其他过程相关的 mRNA 的时间依赖性和基因型特异性调节。这些结果表明，如果直播后不有效管理稻田深度，AG1/TPP7和SUB1/SUB1A-1之间的相互作用可能会影响幼苗的建立。