Behnam Tahmasebpour; Sodabeh Jahanbakhsh; Ali Reza Tarinejad; Hamid Mohammadi; ali ebadi
Abstract
Objective: 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.Methods: To identify ...
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Objective: 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.Methods: 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.Results: 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.Conclusion: 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.
Mehdi Ghaffari
Abstract
To study the effect of row spacing and plant density on agronomic traits of dual purpose sunflower; cultivar Lakomka two years' study from 2014 was carried out as a factorial experiment based on RCB design with four replications in Khoy. The experimental treatments included row spacing at two levels ...
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To study the effect of row spacing and plant density on agronomic traits of dual purpose sunflower; cultivar Lakomka two years' study from 2014 was carried out as a factorial experiment based on RCB design with four replications in Khoy. The experimental treatments included row spacing at two levels (60 and 75 cm) and five plant densities (30, 45, 60, 75 and 90 thousands P ha-1). According to the results there were no significant difference between 60 and 75 cm row spacing for any of the studied traits; however plant density had significant effect on all of the traits. Phenological stages accelerated and head diameter decreased but plant height and oil content increased as plant density increased. Seed weight decreased from115 g to 84 g while oil content increased from 36% to 39% as plant density increased from 30 to 90000 P.ha-1. The highest seed and oil yields (4132 and 1611 kg ha-1) were observed in plant density of 75000 P.ha-1. The regression analyses revealed that oil content, plant height and seed number, are the most effective traits for predictor of oil yield. The results of this study indicated that plant densities of 75 and 45000 P.ha-1 are optimum densities for production of cultivar Lakomka with higher oil yield and as confectionary use in Khoy, West Azarbaijan.
Borzo Kazerani; Saied Navabpour; Hossein Sabouri; Seyedeh Sanaz Ramezanpour; Khalil Zaynali Nezhad; Ali Eskandari
Abstract
To determine the best selection indices for facilitating the selection procedure in a reproductive stage of 96 mutant lines (M2) of rice under different moisture conditions, an experiment was carried out in two environments at the research farm of Gonbad Kavous University in 2016 base on randomized complete ...
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To determine the best selection indices for facilitating the selection procedure in a reproductive stage of 96 mutant lines (M2) of rice under different moisture conditions, an experiment was carried out in two environments at the research farm of Gonbad Kavous University in 2016 base on randomized complete block design with three replications. Evaluating the reduction percentage in the average values of traits showed that the most damages as affected by drought stress was due to decreases in numbers of filled grains, numbers of tillers, and 1000-grain weight. Results of stepwise regression analysis indicated that 1000-grain weight, plant height, numbers of filled grains, numbers of days to flowering, flag leaf rolling, numbers of tillers, and panicle length traits were respectively entered into the final multivariate regression model as important traits affecting grain yield under a flooded condition, and 1000-grain weight, numbers of days to flowering, plant height, fertility percentage, panicle length, flag leaf frying, and numbers of tillers were respectively entered under drought stress. Evaluation of direct and indirect effects of studied traits on the grain yield using a path analysis showed that, 1000-grain weight, due to a positive and high direct effect, and numbers of filled grains, due to an indirect effect via 1000-grain weight, can be considered as the most important traits for increasing the grain yield under flooded condition. However, 1000-grain weight and fertility percentage can be introduced as appropriate selection criteria for the grain yield under a drought condition.