Mahdavi Soraya, Arzani Ahmad, Mirmohammady Maibody S A M, Kadivar Mahdi
Department of Agronomy and Plant Breeding, College of Agriculture, Isfahan University of Technology, Isfahan 8415683111, Iran.
Department of Food Science and Technology, Isfahan University of Technology, Isfahan 8415683111, Iran.
Saudi J Biol Sci. 2022 Oct;29(10):103417. doi: 10.1016/j.sjbs.2022.103417. Epub 2022 Aug 17.
Heat stress during the grain-filling period is the main abiotic stress factor limiting grain yield and quality in wheat ( L.). In this study, 64 wheat genotypes were exposed to heat stress during reproduction caused by delayed sowing in two growing seasons. Grain yield, 1000 grain weight (GW), grain hardness (GH), and grain-quality related traits were investigated. Heat stress caused a significant decrease in GW through reducing starch content (SC) and a non-compensating rise in protein content (PC), and thereby resulted in lower yield. In addition, significant increases in flour water absorption (WA), Zeleny sedimentation volume (ZT), ash content (AC), lipid content (LC), loaf volume (LV), wet gluten content (WG), dry gluten content (DG), gluten index (GI), and amylopectin content (APC) were found following heat stress. In contrast, decreases in grain moisture content (MC) and amylose content (AMC) induced by heat stress were observed. The heat-tolerant genotypes were superior in grain yield, GW, SC, AMC, and MC. While the sensitive genotypes contained higher PC, LV, GI and AMP. A group of wheat genotypes characterized with a higher yield, AMC, GW, and SC as well as lower PC, WA, GH, ZT, and LV; and was found to be the most heat tolerant by principal component analysis. Lighter weight and smaller grains produce a smaller starchy endosperm with lower quality (less amylose) and higher grain protein content in heat stress compared to normal conditions. Heat stress caused by delayed sowing improves some of the baking-quality related traits.
灌浆期的热胁迫是限制小麦（L.）籽粒产量和品质的主要非生物胁迫因素。在本研究中，64个小麦基因型在两个生长季节因晚播而在生殖期遭受热胁迫。对籽粒产量、千粒重（GW）、籽粒硬度（GH）和籽粒品质相关性状进行了研究。热胁迫通过降低淀粉含量（SC）导致GW显著下降，同时蛋白质含量（PC）出现非补偿性升高，从而导致产量降低。此外，热胁迫后发现面粉吸水率（WA）、泽伦尼沉降体积（ZT）、灰分含量（AC）、脂质含量（LC）、面包体积（LV）、湿面筋含量（WG）、干面筋含量（DG）、面筋指数（GI）和支链淀粉含量（APC）显著增加。相反，观察到热胁迫导致籽粒含水量（MC）和直链淀粉含量（AMC）降低。耐热基因型在籽粒产量、GW、SC、AMC和MC方面表现优异。而敏感基因型含有较高的PC、LV、GI和AMP。通过主成分分析发现，一组小麦基因型具有较高的产量、AMC、GW和SC，以及较低的PC、WA、GH、ZT和LV，被认为是最耐热的。与正常条件相比，在热胁迫下，较轻和较小的籽粒产生的淀粉胚乳质量较低（直链淀粉较少）且籽粒蛋白质含量较高。晚播引起的热胁迫改善了一些与烘焙品质相关的性状。
