Water scarcity is known to be a strong limiting factor affecting maize grown and yield in cold semi-arid regions. Numerous studies have shown that rehydration improves maize growth. Our study aimed to explore the effects of rehydration treatments on maize growth and yield under water and nitrogen stress during different growth stages. We selected the drought-tolerant maize variety Nendan 19 (ND19) and subjected it to water stress during the V6 (sixth-leaf), R2 (filling) and R6 (maturity) growth stages and a rehydration treatment after each stress stage. Our results indicated that N1 (N100 kg N ha⁻¹) and N3 (N300 kg N ha⁻¹) treatments significantly increased the leaf moisture status relative to water content (RWC), bound water content (BWC), free water content (FWC) and water potential (WP)) at different growth stages. Similar trends were observed in the accumulation of plant leaf and root hormones (zeatin+zeatin riboside, indole-3-acetic acid, abscisic acid and gibberellic acid), photosynthetic pigments and chlorophyll fluorescence. However, under the same water stress conditions, they decreased as the N rate increased and reached a minimum value in the S3 (water stress for N3) treatments. In addition, with growth stage advancement and extension of the rehydration time, both showed a gradual upward trend. The results showed that to save water resources in the cold semi-arid region, rehydration treatments (R2S1 and R2S3) significantly increased the photosynthetic pigments and chlorophyll fluorescence parameters, leaf moisture status, biomass, 100-grain weight, hormone content, ear characteristics and grain yield of maize.

中文翻译：

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氮胁迫和水分胁迫对玉米补水、内源激素调节和产量的影响

众所周知，缺水是影响寒冷半干旱地区玉米种植和产量的一个重要限制因素。大量研究表明，再水化可以促进玉米生长。本研究旨在探讨不同生育阶段补水处理对水氮胁迫下玉米生长和产量的影响。我们选择了耐旱玉米品种 Nendan 19 (ND19)，并在 V6（第六叶）、R2（灌浆）和 R6（成熟）生长阶段对其进行水分胁迫，并在每个胁迫阶段后进行补水处理。我们的结果表明 N1 (N100 kg N ha ^-1 ) 和 N3 (N300 kg N ha ^-1) 处理显着提高了不同生长阶段的叶片含水量 (RWC)、束缚水含量 (BWC)、自由水含量 (FWC) 和水势 (WP)）。在植物叶和根激素（玉米素+玉米素核苷、吲哚-3-乙酸、脱落酸和赤霉酸）、光合色素和叶绿素荧光的积累中观察到类似的趋势。然而，在相同的水分胁迫条件下，它们随着施氮量的增加而降低，并在 S3（N3 的水分胁迫）处理中达到最小值。此外，随着生育阶段的推进和补液时间的延长，均呈逐渐上升的趋势。结果表明，寒冷半干旱地区要节约水资源，