Investigation of the effect of above sea level on quantitative characteristics of Pistacia atlantica seeds in North Zagros forests

Plant seeds are the main sources of natural reproduction. Lack of natural reproduction in the Zagros forests is due to lack of healthy, ripe and quality seeds. In addition to the genetic characteristics of trees, environmental factors are also effective in producing healthy and quality seeds. This study wasis performed in order to investigate the effect of above sea level on the quantitative characteristics of Pistacia atlantica seeds in Kolahanokan reserve, which is one of the pistacia atlantica reserves in West Azerbaijan province. Unlike other similar researches, in order to Investigate the effect of sea level, the reservoir is divided into 5 classes with a height difference of 100 meters, including 1550-1650, 1650-1750, 1750-1850, 1850-1950, 1950- 2050 meters more ever, in order to increase the height, the reserve area was divided into 77 sample plots of one hectare (100m × 100 m). In each sample plot, three seed-giving trees including the thickest, smallest and one middle diameter were selected under the same conditions (slope factor, slope direction and soil). A total of 150 trees were selected and 5 clusters from each rootstock were randomly collected in the north, south, east, west and center of the crown collection and physical characteristics of seeds including: cluster length, ‌ number of fruits per cluster, fruit length, fruit width, fruit weight, grain weight and seedlessness percentage in each altitude class were evaluated. Analysis of variance and comparison of means were performed using F test, Duncan multiple comparison test and Kruskal-Wallis test, respectively.s