University of Tehran perss Journal of Crops Improvement 2008-8337 26 3 2024 09 22 Investigating the Relationships between Grain Yield and Other Traits of Wheat Genotypes under Moisture Stress in the Flowering Stage Investigating the Relationships between Grain Yield and Other Traits of Wheat Genotypes under Moisture Stress in the Flowering Stage 519 543 97974 10.22059/jci.2024.357029.2802 FA Behnam Tahmasebpour Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran. Sodabeh Jahanbakhsh Department of Plant Genetics and Production Engineering, Faculty of Agriculture and Natural Eesources, University of Mohaghegh Ardabili, Ardabil, Iran. Ali Reza Tarinejad Department of Agricultural Biotechnology, Faculty of Agriculture, Azarbaijan Shahid Madani University, Tabriz, Iran. Hamid Mohammadi Department of Agronomy and Plant Breeding, Faculty of Agriculture, Azarbaijan Shahid Madani University, Tabriz, Iran. Ali Ebadi Department of Plant Genetics and Production Engineering, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran. Journal Article 2023 03 25 <strong>Objective: </strong>The objective of this study was to investigate the relationships between yield and yield components with morphological traits, and to leverage these relationships to select high-yielding cultivars under optimal irrigation and drought stress conditions at the flowering stage.<br /><strong>Methods:</strong> To identify the correlations and relationships among different traits in bread wheat, 30 genotypes were investigated as sub-factors in a split-plot experiment with a completely randomized design and three replications under conditions of normal irrigation and moisture stress at the beginning of the flowering stage at the research greenhouse of Azerbaijan Shahid Madani University in the 2016-2017 crop season.<br /><strong>Results: </strong>Under normal conditions, the number of seeds in a spike (0.89) and under stress conditions, the number of seeds in a spike (0.70) and the number of days from planting to 50% flowering (-0.60) were decisive and influential on the grain yield. The results of canonical correlation analysis showed a significant correlation between the pair of canonical variables obtained from spike traits with grain yield per plant and spike density under both normal and stress levels.<br /><strong>Conclusion: </strong>Grain number per spike, spike length, 1000-grain weight, straw yield, spike and shoot density, flag leaf area, and the duration from planting to 50% flowering are the most critical components significantly impacting crop yield enhancement under optimal greenhouse irrigation conditions. Conversely, the critical determinants of grain yield enhancement included grain filling rate, grain filling period, number of days from planting to 50% flowering, root dry weight, straw yield, and grain number per spike when subjected to moisture stress conditions. <strong>Objective: </strong>The objective of this study was to investigate the relationships between yield and yield components with morphological traits, and to leverage these relationships to select high-yielding cultivars under optimal irrigation and drought stress conditions at the flowering stage.<br /><strong>Methods:</strong> To identify the correlations and relationships among different traits in bread wheat, 30 genotypes were investigated as sub-factors in a split-plot experiment with a completely randomized design and three replications under conditions of normal irrigation and moisture stress at the beginning of the flowering stage at the research greenhouse of Azerbaijan Shahid Madani University in the 2016-2017 crop season.<br /><strong>Results: </strong>Under normal conditions, the number of seeds in a spike (0.89) and under stress conditions, the number of seeds in a spike (0.70) and the number of days from planting to 50% flowering (-0.60) were decisive and influential on the grain yield. The results of canonical correlation analysis showed a significant correlation between the pair of canonical variables obtained from spike traits with grain yield per plant and spike density under both normal and stress levels.<br /><strong>Conclusion: </strong>Grain number per spike, spike length, 1000-grain weight, straw yield, spike and shoot density, flag leaf area, and the duration from planting to 50% flowering are the most critical components significantly impacting crop yield enhancement under optimal greenhouse irrigation conditions. Conversely, the critical determinants of grain yield enhancement included grain filling rate, grain filling period, number of days from planting to 50% flowering, root dry weight, straw yield, and grain number per spike when subjected to moisture stress conditions. https://jci.ut.ac.ir/article_97974_1463ef39ad30bcbde40e5e3e3c70738e.pdf