Study on the distribution of wild pistachio species in Fars province.

Pistacia L. (Anacardiaceae) is mainly a subtropical genus comprising some 10 species of diocious trees and shrubs. P.atlantica and P.khinjuk are two most important species of wild pistachio in Irano-Toranian region. The area of wild pistachio stations in Fars province is about 3220000 ha that includes four main type, Acer- pistacia, Amygdalus-pistacia, pistacia and Quercus-pistacia. Most of these stations exist in 1000-2000m above sea level with 15%-30% slop. The main geographical aspect of these sites is usually either South or North. The great geological formations in these sites are Quaternary and Asmary formation. The soils of these stations usually have light texture, without structure and other conditions of arid and semi arid region with Carbonatic base. In base of improved De' Marton method, most of wild pistachio stations have the Cool- semi arid, Arid dessert and Template-Semiarid climate. According to random sampling in Marvdasht and Arsenjan wild pistachio forest, the mean number of trees and shrubs in hectare was 192, of which 55% was P.atlantica. The basal area was 6.95 m2/ha, of which 70% was from P.atlantica. The mean of crown cover was 12.7%. The regeneration was very poor. In phenological study in Firoozabad and Arsenjan, blooming starts in early April, flowering of male trees happens in the mid-April, and in female trees it happens 4-7 days later. The leaf buds break in mid-April, turn yellow in September, and shed in autumn. The fruit spike is formed in early May and ripens in mid-September. All of the phenological phenomena except leaf shed in Firoozabad happen earlier than those of Arsenjan. 88 The weight of 1000 seeds of P.atlantica from Firoozabad was 314.8g with 32% moisture and 9.3, 6.9, 5.5mm dimension. The weight of 1000 seeds of P.atlantica from Neyriz was 243g with 28% moisture and 8.7,6.2,5.3 mm dimension. The weight of 1000 seeds of P.khinjuk from Mamassani was 87g with 25% moisture and 6.9,5.8, 4.6-mm dimension. In viability study, using of cold/ acid+cool treatment resulted the most generation ratio. The most important pests in this forest are Ocneria terebintina; Thaumetopa solitaria and Hystrix sp. Overgrazing and overexploitation of wild pistachio seeds as well as land conversion are the other cusses of forest decreasing in Fars province. Key words: P.atlantica, P.khinjuk, slop, height from sea level, aspect, geology, soil, clima, basal area, crown cover, phenology, viability, pests and diseases