ANALYSIS OF THE MORPHOLOGICAL VARIABILITY OF PISTACIA ATLANTICA DESF. (ANACARDIACEAE) IN THE ARID AND SEMI-ARID REGIONS (MSILA, ALGERIA)

The Atlas pistachio (Pistacia atlantica) is a rustic and endemic tree from North Africa. It conserves the soils and contributes to the reforestation programs in the arid and semi-arid regions. This study focused on 05 populations of Atlas pistachio in different stations in the region of Msila. It aimed at determining the morphological and physiological variability of the species in different climatic conditions. In total, 25 characteristics were measured for the soil, the leaves, the trees, and the fruits. The statistical analysis of the physic-chemical parameters of the soil allowed separating the study populations into two groups (group 01: Elhamel (El), Sidi Mhamed (SM), and group 02: Elguerssa (EG), Sidi Ameur (SA), and Tamsa (TA). For the morphological variability, two groups of stations were found (group 01: SA, TA, and SM and group 02: EG and EL). The analysis of the main components showed a correlation between the dimensions of the tree, the leaves with the soil properties (the lime rate and the soil humidity), and the effect of the climatic factors. The smallest leaves are found in the high stations while the biggest are in the low stations.