Direct-seeding of rice has become popular in recent years due to its low cost and convenience, however, hypoxic condition limits seedling establishment. In this study, weedy rice WR04-6 with high germination ability under anaerobic conditions was used as a gene donor, and we successfully improved the seedling establishment rate of rice cultivar Qishanzhan (QSZ) based on selection of a new rice line R42 from the recombinant inbred line population. R42 inherited high anaerobic germination (AG) ability, and was used for isobaric tags for relative and absolute quantitation (iTRAQ)-based comparative proteomic studies with QSZ to further explore the molecular mechanism of AG. A total of 719 differentially abundant proteins (DAPs) were shared by R42 and QSZ responded to AG, and thus defined as common response DAPs. A total of 300 DAPs that responded to AG were only identified from R42, which were defined as tolerance-specific DAPs. The common response and tolerance-specific DAPs had similar biochemical reaction processes and metabolic pathways in response to anoxic stress, however, they involved different proteins. The tolerance-specific DAPs were involved in amino acid metabolism, starch and sucrose metabolism, tricarboxylic acid cycle pathway, ethylene synthesis pathway, cell wall-associated proteins and activity of active oxygen scavenging enzyme. The in silico protein-protein interactions for the top 60 DAPs indicated that tolerance-specific DAPs had relatively independent protein interaction networks in response to an anoxic environment compared with common response DAPs. The results of physiological indicators showed that α-amylase and superoxide dismutase activities of R42 were significantly increased under anoxic conditions compared with aerobic conditions. Multiple lines of evidence from western blot, physiological analysis and quantitative real-time PCR jointly supported the reliability of proteomics data. In summary, our findings deepened the understanding of the molecular mechanism for the rice response to AG.

水稻直播由于成本低、方便等优点，近年来越来越流行，但缺氧条件限制了秧苗的建立。本研究以厌氧条件下具有高发芽能力的杂草稻 WR04-6 作为基因供体，基于重组水稻新品系 R42 的选择，成功提高了水稻品种齐山占（QSZ）的成苗率。近交系种群。R42 继承了高厌氧萌发 (AG) 能力，并被用于同量异位标记以进行基于相对和绝对定量 (iTRAQ) 的比较蛋白质组学研究，以进一步探索 AG 的分子机制。R42 共有 719 种差异丰富的蛋白质 (DAP)，QSZ 对 AG 有反应，因此定义为共同反应 DAP。总共有 300 个响应 AG 的 DAPs 仅从 R42 中识别出来，它们被定义为耐受性特定的 DAPs。共同反应和耐受性特异性 DAPs 对缺氧应激反应具有相似的生化反应过程和代谢途径，但它们涉及不同的蛋白质。耐受特异性DAPs参与氨基酸代谢、淀粉和蔗糖代谢、三羧酸循环途径、乙烯合成途径、细胞壁相关蛋白和活性氧清除酶的活性。这 耐受特异性DAPs参与氨基酸代谢、淀粉和蔗糖代谢、三羧酸循环途径、乙烯合成途径、细胞壁相关蛋白和活性氧清除酶的活性。这 耐受特异性 DAPs 参与氨基酸代谢、淀粉和蔗糖代谢、三羧酸循环途径、乙烯合成途径、细胞壁相关蛋白和活性氧清除酶的活性。这前 60 个 DAP 的计算机蛋白质-蛋白质相互作用表明，与普通反应 DAP 相比，耐受性特异性 DAP 具有相对独立的蛋白质相互作用网络，以响应缺氧环境。生理指标结果表明，与有氧条件相比，缺氧条件下R42的α-淀粉酶和超氧化物歧化酶活性显着提高。来自蛋白质印迹、生理分析和实时定量 PCR 的多条证据共同支持蛋白质组学数据的可靠性。总之，我们的研究结果加深了对水稻对 AG 反应的分子机制的理解。