The study of Heritability, correlation and path analyses on genotypes of black saxaul (Haloxylon aphyllum)

Haloxylon species have several capabilities for which they can resist harsh conditions of deserts as well as playing an important role in the fixation of sand dunes. Accordingly, progenies of 27 mother trees collected from their habitats were studied in a repeated statistical experiment. Heritability values were estimated for vegetative characteristics of plant height, crown diameter, and collar diameters of the single plants. Analysis of variance revealed that the genotypes were significantly different in all the six years of the study but the level of significance were lower for early years than that of last year of the study period. Genetic components of variance and heritability also showed an increasing trend during the study period. The difference between the mother plants were more remarkable in final year of the study period, implying that due to low vegetative growth speed of the species, it would not reveal its complete potentials at early growth stages. The result showed medium significant correlation of investigation. Traits Plant hight, Survival, Crown smaller diameter, Heigh of first branches and Number of branches on main inter to model studied by path analysis. Result showed that Plant hight, Survival, Number of branches on main hand has the greatest direct and positive effect on Crownlarge diameter. Likewise, 4 principal components approximately explained 71.5% of total variance. Totally, in order to increase the coverage and improve direct crown large diameter, respectively, both principal components should be considered. In other words, plant height, survival and the number of branches in the main hand were the topics that should be highly regarded.