Main conclusion In response to low nitrogen stress, multiple hormones together with nitric oxide signaling pathways work synergistically and antagonistically in crop root elongation. Abstract Changing root morphology allows plants to adapt to soil nutrient availability. Nitrogen is the most important essential nutrient for plant growth. An important adaptive strategy for crops responding to nitrogen deficiency is root elongation, thereby accessing increased soil space and nitrogen resources. Multiple signaling pathways are involved in this regulatory network, working together to fine-tune root elongation in response to soil nitrogen availability. Based on existing research, we propose a model to explain how different signaling pathways interact to regulate root elongation in response to low nitrogen stress. In response to a low shoot nitrogen status signal, auxin transport from the shoot to the root increases. High auxin levels in the root tip stimulate the production of nitric oxide, which promotes the synthesis of strigolactones to accelerate cell division. In this process, cytokinin, ethylene, and abscisic acid play an antagonistic role, while brassinosteroids and auxin play a synergistic role in regulating root elongation. Further study is required to identify the QTLs, genes, and favorable alleles which control the root elongation response to low nitrogen stress in crops.

中文翻译：

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作物缺氮引起根系伸长的生理机制

主要结论 为应对低氮胁迫，多种激素与一氧化氮信号通路在作物根系伸长中协同和拮抗作用。摘要 改变根系形态使植物能够适应土壤养分的有效性。氮是植物生长最重要的必需营养素。作物应对氮缺乏的一个重要适应性策略是根系伸长，从而获得更多的土壤空间和氮资源。该调节网络涉及多个信号通路，共同作用以微调根系伸长以响应土壤氮的可用性。基于现有研究，我们提出了一个模型来解释不同的信号通路如何相互作用以调节根系伸长以响应低氮胁迫。响应于低芽氮状态信号，从芽到根的生长素转运增加。根尖中的高生长素水平会刺激一氧化氮的产生，从而促进独脚金内酯的合成，从而加速细胞分裂。在这个过程中，细胞分裂素、乙烯和脱落酸起拮抗作用，而油菜素内酯和生长素在调节根伸长中起协同作用。需要进一步研究以确定控制作物根系伸长响应低氮胁迫的 QTL、基因和有利等位基因。和脱落酸起拮抗作用，而油菜素内酯和生长素在调节根伸长中起协同作用。需要进一步研究以确定控制作物根系伸长响应低氮胁迫的 QTL、基因和有利等位基因。和脱落酸起拮抗作用，而油菜素内酯和生长素在调节根伸长中起协同作用。需要进一步研究以确定控制作物根系伸长响应低氮胁迫的 QTL、基因和有利等位基因。