Combining ability between males and females of pistacia atlantica to select the best parents for artificial crosses.

Present research work has been conducted using parental pistachia atlantica plants and their progenies in some provinces of Iran. The sites and trees were selected in Tehran, Fars, Markazi, Kerman and west Azerbaijan and in next step crossing of some paternal and maternal trees have followed according to line tester method in Tehran, Fars, and west Azarbaijan. Data collected from forest areas, greenhouse as well as laboratory. Selections of Full & Half Sibs were used after analyzing GCA and SCA. It was found that the trees of pistachia atlantica in candidate sites having capability of 19 to 39% oil production. Progenies were examined for 100 seed weight, germination percentage, and growth rate and establishment percentage. It was found that there are positive and significant correlation between seedling&rsquos height and stem height and stem height&rsquos and stem diameter but negative and significant correlation was found between oil percentage and seed size. Male 4 and 5 have effective role in oil production when crossed to different maternal trees. This effect in Full Sibs has shown to be more productive than all the Half Sibs in all provinces. According to our research results, the best paternal combiners are 4 & 5 with GCA 3.91 & 2.30 and the best combiner female trees are 8 & 13. In Fars province, General Combining Abilities for improving some characteristics such as germination percentage were calculated. The highest value was found to be in male 2 when crossed with females 4 & 13. GCA in mentioned male was 2.04 which is higher than all other GCAs. Highest values of 100 seed weight were found when male 2 crossed with females 2 & 10. GCA in male 2 is 11.82 and is higher than all others. The best female combiners were 12 & 6 with 9.36 & 4.82 of GCA respectively when crossed with males 2, 5 & 7(in female12) and 2 & 6(in female 6). In seed germination, highest value was found in males 12 & 13 when crossed with all females. The best female combiners were 7, 10 & 11 with 12.3, 9.23 & 7.31 GCA respectively. Within paternal trees, males 7, 8 & 9 with GCA 7.87, 16.5 & 7.54 respectively have been the best combiners. It has to be mentioned that the male 9 has capability to show high GCA and mean in all measured characteristics. In eastern Azerbaijan, the highest fruitfulness percentage related to crossed 9 male with 3 & 11 females. GCA in male 9 was 36.6 which is more than GCA of all other males. Meanwhile, the best female combiner has shown to be female10 with 8.77 GCA when crossed with males 9 & 13. Number of seed production was seen to be highest in male 9 when crossed with female 9 & 11. GCA in above mentioned male was 49.64 which were more than all others. The best mother tree combiner was 11 with 8.9 GCA when crossed with 9 male. The best germination percentage in eastern Azerbaijan was found in males 12 & 13 in all of their crossings. The best GCA were seen in maternal trees 7, 10 & 11 with 12.3, 9.23 & 7.31 respectively while GCA for males were found in7, 8 & 9 with 7.87, 16.5 & 7.54 respectively.