The purpose of this work was to investigate how different nutrition systems (N0: 0:0, N1: 100:0, N2: 75:25, N3: 50:50, N4: 25:75, and N5: 0:100 kg ha nitrogen from urea and organic fertilizer sources respectively) affect the physiological characteristics and yield of safflower ( L.) under different irrigation regimes. These irrigation regimes include complete irrigation (S0), irrigation cut-off at stem elongation (S1), flowering and pollination (S2), and grain filling (S3) stages. The S1 irrigation level led to a decrease in Fv/Fm (5 %), relative water content (RWC) of the leaf (17 %), leaf total chlorophyll (22 %), and soluble proteins of the leaf (21 %) an increase in electrolyte leakage (33 %), carotenoids (43 %), proline content (42 %) and soluble sugars of the leaf (39 %) compared with S0 irrigation level. The safflower leaf showed increased Fv/Fm, RWC, total chlorophyll, and soluble proteins when organic fertilizer was used alone or in combination with chemical fertilizers under irrigation cut-off conditions. Additionally, the use of organic fertilizer resulted in a decrease in carotenoid content, proline content, and soluble sugars of the safflower leaf. The highest biological yield was obtained with S0 irrigation level (21.62 t ha) and N3 integrated nutrition system (21.93 t ha), respectively. The N3 and N2 nutrition systems increased the grain yield by 3.34 t ha and 3.56 t ha in 2015 and 2016, respectively. The greatest negative effect on biological yield was observed when irrigation was cut-off during the vegetative stage, while the most detrimental impact on grain yield occurred when irrigation was ceased during the flowering and pollination stages. Overall, the results indicated that N2 and N3 nutrition systems while implementing irrigation cut-off at various growth stages reduced the negative impact of water deficiency on plants. This leads to decreased production costs for stress-resistant osmolytes and, consequently, improved grain yield and biological yield.

中文翻译：

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不同灌水条件下有机氮与化学氮结合改善红花生理特性和产量


这项工作的目的是调查不同的营养系统（N0: 0:0、N1: 100:0、N2: 75:25、N3: 50:50、N4: 25:75 和 N5: 0:100 kg）尿素和有机肥氮源分别影响红花（L.）在不同灌溉方式下的生理特性和产量。这些灌溉制度包括完全灌溉（S0）、茎伸长阶段停止灌溉（S1）、开花和授粉阶段（S2）以及灌浆阶段（S3）。 S1 灌溉水平导致 Fv/Fm (5%)、叶片相对含水量 (RWC) (17%)、叶片总叶绿素 (22%) 和叶片可溶性蛋白 (21%) 下降，与 S0 灌溉水平相比，电解质渗漏 (33%)、类胡萝卜素 (43%)、脯氨酸含量 (42%) 和叶片可溶性糖 (39%) 增加。在停灌条件下，单独使用有机肥或与化肥结合使用时，红花叶片的 Fv/Fm、RWC、总叶绿素和可溶性蛋白质均有所增加。此外，施用有机肥导致红花叶的类胡萝卜素含量、脯氨酸含量和可溶性糖含量下降。 S0灌溉水平（21.62 t ha）和N3综合营养系统（21.93 t ha）分别获得最高的生物产量。 N3和N2营养系统在2015年和2016年分别增加了粮食产量3.34吨公顷和3.56吨公顷。当在生长期停止灌溉时，对生物产量的负面影响最大，而对谷物产量的最不利影响则发生在开花和授粉阶段停止灌溉时。 总体而言，结果表明，N2和N3营养系统同时在各个生长阶段实施停灌，减少了缺水对植物的负面影响。这导致抗逆渗透剂的生产成本降低，从而提高谷物产量和生物产量。