Comparison of morphological and chemical properties of wild pistachio (Pistacia atlantica) fruit across two habitats in Kurdistan Province

To evaluate a number of important traits of wild paistachio (Pistacia atlantica) fruit, this study was conducted in two of of its natural habitats in Kurdistan province, including Mazevanband (Baneh) and Dezli (Sarvabad) during 2007-2008. In each habitat, a total number of 30 uniform trees were selected. From each sample tree, 10 fruit samples each weighting 200 g were taken in late October. The traits were measured in labratory. Analysis of variance (ANOVA) using nested method was followed by Duncan test to compare the means. ANOVA results revealed significant differences (P ≤ 0.01) between habitats (Sarvabad and Baneh) across all the studied traits, as well as across trees within each habitat for all traits except fruit size. The average diameter at breast height (D) was 69.7 cm, seedless fruit percentage (SLFP) accounted for 20.83%, the average fruit length (FL) and fruit width (FWi) were 5.41 and 6.33 mm respectively, fruit size (fruit width × length) (FWi×FL) was equivalent to 34.48 mm2, the mean weight of complete fruit (FW), seedless fruit (SLFW), backless fruit (fruit without peel) (BLFW) and seed (SW), were 2.15, 1.46, 1.47 and 0.51 g respectively. In addition, seed weight to fruit weight ratio (SW/FW) was 0.24, and mean percentage of oil content (OC%) was 26.86 %. The average of all studied traits except tree diameter and fruit oil in Baneh was generally more than in Sarvabad. Moreover, the regression analysis of oil content on the other traits as independent variables revealed that the regression coefficient of oil content on backless fruit weight (fruit without skin) (BLFW) and seed weight (SW) were positive and significant (P ≤ 0.01), while they were negative and significant(P ≤ 0.01) for seedless fruit percentage (SLFP) and seedless fruit weight (SLFW), as well as positive and significant (P ≤ 0.05)for ratio of seed weight to fruit weight (SW/FW). Thus, the oil content percentage of trees is concluded to be improved by selection of the individuals featuring higher fruit and seed weights.