Evaluation of general combining ability for vegetative traits in male and female parents of pistacia atalntica

The aim of this study was to evaluate the general combining ability of vegetative traits of Pistcia atlantica. For this purpose 10 male trees were crossed with seven female trees in the Islamic island of Lake Urmia in 2003. The hybrid seeds were sown in the Forest and Rangeland Research Institute. Annual growth mean and collar diameter of progenies measured at 2006, 2007 and 2017; the canopy area and trunk wood volume were measured in 2017. Estimation of the general combining ability based on mean annual growth and collar diameter in the offspring of different crosses in 2006, 2007 and 2017 showed that the best combination were F12 × M10, in 2006, F13 × M6, in 2007 and F13 × M12 in 2017. This indicated that the offsprings showed their potential over time. In the 2017, the F13 × M13 hybrid were the best in terms of annual growth mean, but their produced progenies had the lowest amount growth. Female parent 13 and male parent 9 were the best parents for the collar diameter and canopy surface. In addition, their combination produced offspring with the highest average collar diameter and canopy surface. The results indicate the high heterosis in P. atlantica and its possibility in breeding improved varieties to development of reforestation and rehabilitation of habitats with the aim of producing industrial products, medicines or edible oils and Wood production with higher yield.