灌浆期光资源时空分布不均和水资源匮乏对作物可持续生产构成重大挑战,特别是在中国西北黄土高原的干旱地区。本研究旨在研究干旱和遮荫胁迫对冬小麦生长及其生理生化和抗氧化反应的联合影响。小麦植物受到不同的干旱水平-充分灌溉(I100),全灌溉的75%(I75),充分灌溉的50%(I50),和25%的完全灌溉(I25),和遮光处理-12、9、6、3和0天(SD12、SD9、SD6、SD3和CK,分别)在灌浆阶段。干旱和遮荫处理的影响按降序降低了产量,在SD12和I25治疗中观察到最显著的减少。这些处理降低了谷物产量,每株植物的穗,1000粒重,每穗小穗增加160.67%,248.13%,28.22%,和179.55%,分别,与CK相比。此外,MDA含量和抗氧化酶活性随着灌水减少和遮光时间延长而呈上升趋势。在I75和SD12处理中记录了最高值,增加了MDA,SOD,POD,和禁止酷刑委员会的活动增长了65.22、66.79、65.07和58.38%,分别,与CK相比。Pn,E,Gs,随着遮光时间的增加和灌溉量的减少,iCO2呈下降趋势(318.14、521.09、908.77和90.85%)。干旱和遮光处理损害叶片叶绿素荧光,产量下降和相关的生理生化属性。
The uneven spatial and temporal distribution of light resources and water scarcity during the grain-filling stage pose significant challenges for sustainable crop production, particularly in the arid areas of the Loess Plateau in Northwest China. This study aims to investigate the combined effects of drought and shading stress on winter wheat growth and its physio-biochemical and antioxidative responses. Wheat plants were subjected to different drought levels- full irrigation (I100), 75% of full irrigation (I75), 50% of full irrigation (I50), and 25% of full irrigation (I25), and shading treatments - 12, 9, 6, 3 and 0 days (SD12, SD9, SD6, SD3, and CK, respectively) during the grain-filling stage. The effects of drought and shading treatments reduced yield in descending order, with the most significant reductions observed in the SD12 and I25 treatments. These treatments decreased grain yield, spikes per plant, 1000-grain weight, and spikelets per spike by 160.67%, 248.13%, 28.22%, and 179.55%, respectively, compared to the CK. Furthermore, MDA content and antioxidant enzyme activities exhibited an ascending trend with reduced irrigation and longer shading durations. The highest values were recorded in the I75 and SD12 treatments, which increased MDA, SOD, POD, and CAT activities by 65.22, 66.79, 65.07 and 58.38%, respectively, compared to the CK. The Pn, E, Gs, and iCO2 exhibited a decreasing trend (318.14, 521.09, 908.77, and 90.85%) with increasing shading duration and decreasing irrigation amount. Drought and shading treatments damage leaf chlorophyll fluorescence, decreasing yield and related physiological and biochemical attributes.