Pistachio (Pistacia vera L.) is considered as one of the most important fruit nuts in the world. The present research was conducted on the morphological evaluation of 96 pistachio seedling trees originated from open-pollination to identify the promising genotypes. Significant differences were observed among the studied genotypes based on the measured traits. Nut dry weight ranged from 0.45 to 1.40 g, while kernel weight ranged from 0.17 to 0.80 g, and also kernel percentage varied from 27.84 to 92.17%. In addition, split nut percentage, as a very important characteristic in pistachio, ranged between 0.00 and 97.37%. Split nut percentage showed positive and significant correlations with bunch weight, fruit number per bunch, nut weight, and kernel width. Kernel weight with high standardized beta coefficients (β=0.96, P < 0.00) showed a significant positive association with kernel percentage. Thus, kernel weight is highly influencing kernel percentage and thus should be considered in the breeding programs. Principal component analysis indicated 15 components that explained 75.44% of the total variance. The UPGMA dendrogram showed four different clusters, indicating high phenotypic variation among the genotypes. Based on ideal values of the main traits in pistachio, the genotypes no. 28, 46, 8, 12, 58, 31, 61, 5, 20, 51, 74, 47, 64, 88, 32, and 14 were promising and may be used for cultivation. Furthermore, they may be applied as parents to improve the cultivated ones in the breeding programs.
