Assessment of diversity and identifying of effective traits on grain yield of barley (Hordeum vulgare L.) under non-stress and terminal moisture stress conditions

To evaluate the genetic diversity and detecting the most effective traits on yield of barley promising lines, two separate experiments were conducted based on randomized completely block design with three replications under non- stress and terminal moisture stress conditions. The lines had significant differences for all studied traits in both stress and non-stress conditions. In moisture stress condition, the lines 4, 6 and 9 had the highest and the lines 13, 16 and 17 had the lowest grain yield. Kernel weight per spike and 1000- kernel weight had the most important role for increasing of yield in the six rowed line number 9, while spike number per m2 and 1000- kernel weight were the most effective traits in two rowed lines 4 and 6. Spike number per m2 under non-moisture stress condition and spike number per m2 and 1000- kernel weight under terminal moisture stress condition had significant positive correlations with grain yield. The lines 2, 4 and 10 had the lowest and the lines 1, 13 and 18 had the highest variation for grain yield. Number of spike per m2 was detected as the most effective trait on grain yield in both moisture conditions. Furthermore, kernel weight per spike and peduncle weight under non- stress condition and kernel weight per spike and 1000 kernel weight under moisture stress condition were the most important traits on grain yield. Also, number of spike per m2 and awn length under non-stress condition and number of spike per m2 and stem length under moisture stress condition had maximum and minimum genetic diversity, respectively. The maximum and minimum heritability was also calculated for the number of kernel per spike and awn length, respectively. Results of this research showed that number of spike per m2 with the highest genetic diversity was the most effective trait on grain yield under both non-stress and moisture stress conditions and can be recommended to improve grain yield of the studied barley promising lines.