Nitrogen (N) is one of the most important nutrients for crop plant performance, however, the excessive application of nitrogenous fertilizers in agriculture significantly increases production costs and causes severe environmental problems. Therefore, comprehensively understanding the molecular mechanisms of N-use efficiency (NUE) with the aim of developing new crop varieties that combine high yields with improved NUE is an urgent goal for achieving more sustainable agriculture. Plant NUE is a complex trait that is affected by multiple factors, of which hormones are known to play pivotal roles. In this review, we focus on the interaction between the biosynthesis and signaling pathways of plant hormones with N metabolism, and summarize recent studies on the interplay between hormones and N, including how N regulates multiple hormone biosynthesis, transport and signaling and how hormones modulate root system architecture (RSA) in response to external N sources. Finally, we explore potential strategies for promoting crop NUE by modulating hormone synthesis, transport and signaling. This provides insights for future breeding of N-efficient crop varieties and the advancement of sustainable agriculture.

中文翻译：

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激素信号在调节植物氮利用效率中的作用

氮（N）是作物生长最重要的养分之一，然而，农业中氮肥的过量施用显着增加了生产成本并造成严重的环境问题。因此，全面了解氮利用效率（NUE）的分子机制，开发兼具高产和提高NUE的作物新品种是实现农业可持续发展的迫切目标。植物 NUE 是一个复杂的性状，受多种因素影响，其中激素发挥着关键作用。在这篇综述中，我们重点关注植物激素的生物合成和信号通路与氮代谢的相互作用，并总结了近年来激素与氮相互作用的研究，包括氮如何调节多种激素的生物合成、运输和信号传导以及激素如何调节根系。响应外部N源的系统架构（RSA）。最后，我们探索通过调节激素合成、运输和信号传导来促进作物 NUE 的潜在策略。这为未来高效氮作物品种的育种和可持续农业的进步提供了见解。