Chaouachi Latifa, Marín-Sanz Miriam, Barro Francisco, Karmous Chahine
Laboratory of Genetics and Cereal Breeding (LR14 AGR01), National Institute of Agronomy of Tunisia, Carthage University, 1082 Tunis, Tunisia.
Department of Plant Breeding, Institute for Sustainable Agriculture-Spanish National Research Council (IAS-CSIC), 14004 Córdoba, Spain.
AoB Plants. 2023 Dec 9;16(1):plad085. doi: 10.1093/aobpla/plad085. eCollection 2024 Jan.
The devastating effects and extent of abiotic stress on cereal production continue to increase globally, affecting food security in several countries, including Tunisia. Heat waves and the scarcity of rainfall strongly affect durum wheat yields. The present study aims to screen for tolerance to combined water and heat stresses in durum wheat at the juvenile stage. Three combined treatments were tested, namely: T0 (100% field capacity (FC) at 24 °C), T1 (50% FC at 30 °C), and T2 (25% FC at 35 °C). The screening was carried out based on morphological, physiological, and biochemical criteria. The results showed that the combined stress significantly affected all the measured parameters. The relative water content (RWC) decreased by 37.6% under T1 compared to T0. Quantum yield () and photosynthetic efficiency () decreased under severe combined stress (T2) by 37.15% and 37.22%, respectively. Under T2 stress, LT increased by 63.7%. A significant increase in osmoprotective solutes was also observed, including proline, which increased by 154.6% under T2. Correlation analyses of the combination of water and heat stress confirm that the traits RWC, chlorophyll b content, , proline content, and leaf temperature can be used as reliable screening criteria for the two stresses combined. The principal component analysis highlighted that Aouija tolerates the two levels of stresses studied, while the genotypes Karim and Hmira are the most sensitive. The results show that the tolerance of durum wheat to combined water and heat stress involves several adaptation mechanisms proportional to the stress intensity.
非生物胁迫对全球谷物生产的破坏性影响和程度持续增加,影响了包括突尼斯在内的多个国家的粮食安全。热浪和降雨稀缺严重影响硬粒小麦产量。本研究旨在筛选硬粒小麦幼苗期对水分和热胁迫组合的耐受性。测试了三种组合处理,即:T0(24°C下100%田间持水量(FC))、T1(30°C下50%FC)和T2(35°C下25%FC)。基于形态、生理和生化标准进行筛选。结果表明,复合胁迫显著影响所有测量参数。与T0相比,T1处理下相对含水量(RWC)下降了37.6%。在重度复合胁迫(T2)下,量子产量()和光合效率()分别下降了37.15%和37.22%。在T2胁迫下,LT增加了63.7%。还观察到渗透保护溶质显著增加,包括脯氨酸,在T2处理下脯氨酸增加了154.6%。水分和热胁迫组合的相关性分析证实,RWC、叶绿素b含量、、脯氨酸含量、和叶片温度等性状可作为两种胁迫组合的可靠筛选标准。主成分分析突出表明,奥伊贾(Aouija)能耐受所研究的两种胁迫水平,而基因型卡里姆(Karim)和赫米拉(Hmira)最为敏感。结果表明,硬粒小麦对水分和热胁迫组合的耐受性涉及多种与胁迫强度成比例的适应机制。