Abstract Kale originates from the eastern Mediterranean and Asia Minor, being cultivated worldwide and is considered as global cash crop to high nutrients as well as cold tolerance in the fall, winter, and spring. Although kale production is gradually increasing, there is limited research on physiological and metabolism changes by different levels of irrigation. Here, we comprehensively investigated yield, metabolism, and physiological changes by different levels of precision irrigation based on soil moisture sensor. Kales were grown at three different levels of volumetric water content (VWC) which included 0.15, 0.25, or 0.35 m3 m3, corresponding to well-watered, intermediate drought, and drought stressed conditions. There was a 22.5% increase in fresh weight when comparing the 0.15 to 0.35 m3 m3 VWC treatments. Leaf transpiration (E), net CO2 assimilation rate (A), intercellular CO2 concentration (Ci), tand stomatal conductance (gs) to water vapor were significantly different between 0.15 and 0.35 m3 m3 VWC treatments. The carotenoids neoxanthin and antheraxanthin were significantly decreased when comparing the 0.15 to 0.35 m3 m3 VWC treatments. Additionally, aspartic acid and glutamate were highest concentration at 0.35 VWC, implying well-watered condition has a high assimilation capacity from nitrate and ammonium in the kale plant leaf tissue. Glycine, histidine, proline, fructose, and glucose were increased as VWC decreased, indicating that these metabolites are indicators of drought stress. Linoleic acid, and the glucosinolates glucoiberin, progoitrin, sinigrin, and total phenolic content were the highest concentration in the 0.25 m3 m3 VWC, indicating moderate drought stress may increase these specific metabolites. From the pathway analysis, drought stress significantly increased alanine, aspartate, and glutamate metabolism and glycine, serine, and threonine metabolism. Deficit irrigation that induce drought stress impacted kale plants by decreasing physiological (A, E, and gs) parameters and metabolite (carotenoids, chlorophylls) concentrations, while increase stress induced metabolites such as proline and glutamate. Thus, this study utilized a comprehensive research methodology that connects morphophysiological and biochemical metabolite information and demonstrates how kale plants may integrate growth in drought conditions.

中文翻译：

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羽衣甘蓝 (Brassica oleracea L. var. acephala) 的不同精确灌溉阈值会导致生理性能、代谢物和产量的变化

摘要 羽衣甘蓝原产于地中海东部和小亚细亚，在世界范围内均有栽培，被认为是全球性经济作物，秋、冬、春季季营养丰富，耐寒。尽管羽衣甘蓝产量在逐渐增加，但对不同灌溉水平对生理和代谢变化的研究还很有限。在这里，我们基于土壤水分传感器，通过不同程度的精准灌溉，综合研究了产量、代谢和生理变化。羽衣甘蓝在三种不同的体积含水量 (VWC) 下生长，其中包括 0.15、0.25 或 0.35 m3 m3，对应于充足浇水、中等干旱和干旱胁迫条件。比较 0.15 至 0.35 m3 m3 VWC 处理时，鲜重增加了 22.5%。叶蒸腾作用（E），0.15 和 0.35 m3 m3 VWC 处理之间的净 CO2 同化率 (A)、细胞间 CO2 浓度 (Ci)、tand 气孔导度 (gs) 对水蒸气有显着差异。比较 0.15 至 0.35 m3 m3 VWC 处理时，类胡萝卜素新黄质和花黄素显着降低。此外，天冬氨酸和谷氨酸在 0.35 VWC 时的浓度最高，这意味着充分浇水的条件对羽衣甘蓝植物叶组织中的硝酸盐和铵盐具有很高的同化能力。随着 VWC 的降低，甘氨酸、组氨酸、脯氨酸、果糖和葡萄糖增加，表明这些代谢物是干旱胁迫的指标。亚油酸、芥子油苷、芥子油苷、黄芪甲苷、红花苷和总酚含量在 0.25 m3 m3 VWC 中的浓度最高，表明适度干旱胁迫可能会增加这些特定代谢物。从通路分析来看，干旱胁迫显着增加了丙氨酸、天冬氨酸和谷氨酸代谢以及甘氨酸、丝氨酸和苏氨酸代谢。导致干旱胁迫的灌溉不足会降低生理（A、E 和 gs）参数和代谢物（类胡萝卜素、叶绿素）浓度，同时增加胁迫诱导的代谢物，如脯氨酸和谷氨酸，从而影响羽衣甘蓝植物。因此，这项研究利用了一种综合的研究方法，将形态生理学和生化代谢物信息联系起来，并展示了羽衣甘蓝植物如何在干旱条件下整合生长。和谷氨酸代谢以及甘氨酸、丝氨酸和苏氨酸代谢。导致干旱胁迫的灌溉不足会降低生理（A、E 和 gs）参数和代谢物（类胡萝卜素、叶绿素）浓度，同时增加胁迫诱导的代谢物，如脯氨酸和谷氨酸，从而影响羽衣甘蓝植物。因此，这项研究利用了一种综合的研究方法，将形态生理学和生化代谢物信息联系起来，并展示了羽衣甘蓝植物如何在干旱条件下整合生长。和谷氨酸代谢以及甘氨酸、丝氨酸和苏氨酸代谢。导致干旱胁迫的灌溉不足会降低生理（A、E 和 gs）参数和代谢物（类胡萝卜素、叶绿素）浓度，同时增加胁迫诱导的代谢物，如脯氨酸和谷氨酸，从而影响羽衣甘蓝植物。因此，这项研究利用了一种综合的研究方法，将形态生理学和生化代谢物信息联系起来，并展示了羽衣甘蓝植物如何在干旱条件下整合生长。