Adaptation of Two Tomato Varieties (Solanum lycopersicon L.) Under Salinity Stress

In order to study the adaptive behavior of two tomato varieties (Solanumlicopersicum L.) Safa and Assila subjected to salt stress with concentrations of (50, 100, 150 and 200 mM) in (NaCl+CaCl2) during the growth phase, a morphological (number of leaves, stem length, stomatal density, length of the main root axis) and physio-biochemical (relative water content, chlorophyll pigments content, soluble sugars content) evaluation was conducted. Our results confirm the sensitivity of both varieties to applied salt stress; this sensitivity was manifested by a statistically significant decrease in: number of leaves, length of the stem and the contents of chlorophyll a and total chlorophyll. While, the soluble sugars content at the leaf level increased associated with an increase stomatal density on both ventral and dorsal epiderms. On the other hand, the ratio of root dry weight and shoot dry weight (RDW/SDW) was decreased with an elongation of the main root according to the different doses of salts.