Genetic evaluation of barley lines for crown freezing resistance and several physiological characters

In order to determine the genetics of barley lines for freezing resistance based on crown survival percentage an experiment was carried out as a split plot design on the basis of randomized complete blocks with two replications. Forty barley lines were assigned in subplots and five freezing temperatures (-8, -11, -13, -15 and -17 ˚С) were allocated in main plots. The results showed significant differences among lines at the temperatures -8, -11 and -13 ˚С. Analysis of variance of the data based on randomized complete block design showed significant differences among lines for LT50, leaf fresh weight, percentage of leaf dry weight, percentage of crown dry weight, percentage of leaf water content, percentage of crown water content, percentage of seedling water content, leaf relative water loss and the amount of proline after hardening. The heritability of LT50, percentage of leaf dry weight, percentage of leaf water content, percentage of seedling water content and amount of proline after hardening were high and amount of proline after hardening had the largest squared genetic coefficient of variation. Grouping of barley lines based on LT50 and survival percentage at the temperatures -8, -11, -13 and -15 ˚С, determined line 36 (Schulyer cultivar) as the most freezing tolerant and based on physiological characters indicated the lines 9 (with the pedigree of Alger/(CI10117/Choyo..), 31 (Makouee cultivar) and 15 (with the pedigree of K-096M3) as the more desirable genotypes.