Estimation of the broad-sense heritability of traits in Haloxylon aphyllum native populations in Kerman

Abstract

To investigate the broad-sense heritability of some Haloxylon traits, an experimental design was performed using native populations collected from different provinces of Iran. 32 native populations were planted based on a randomized complete block design with three replications in Shaheed Zendeh Ruh's research station in Kerman. During three years, seven traits including main stem length, collar diameter, number of tillers, sub-stem length1, sub-stem length2, the small and large diameter of the canopy on shrubs were examined. The data were assessed by simple and combined analysis of variance. For all traits, the difference between the mean of genotypes and years was significant (p < %1). The genotype× year interaction effect was significant for all other traits except the number of tillers, which indicates different effects of genotypes in different years. Heritability of traits was estimated based on simple and combined analysis of variances. The amount of heritability was ranged from 75 to 87% for simple analysis and 51 to 64% for combined analysis, which indicates a decrease in heritability in a combined analysis. This is due to the genotypes by the year interactions effects. In both methods, the main stem length and number of tillers had the highest and lowest broad-sense heritability and coefficients of genetic and phenotypic variation, respectively. Due to the high genetic diversity among the studied Haloxylon genotypes, it will be possible to select the best rootstocks for making windbreaks in desertification projects.