Assessment of Salinity Tolerance of Three Fig Cultivars Based on Growth and Physiological Factors and Ions Distribution

Salinity stress is an important limitation in fig production, especially in arid and semi-arid areas. To investigate the effect of salinity levels (0.6, 4 and 8 dS m-1) on 3 fig cultivars of ‘Sabz’, ‘Peyvas’ and ‘Shahanjir’, a factorial (3×3) experiment was done in a completely randomized design with four replications and some growth and physiological parameters were evaluated. Salinity reduced shoot length and diameter, dry weight of shoots and roots and increased proline in leaves of three cultivars, significantly. Total chlorophyll (Chl) and Chla decreased while no change in Chlb, Chla / Chlb ratio and carotenoids were observed in two Peyvas and Shahanjir cultivars. In cultivar Sabz, no changes in Chla and carotenoids were observed, but Chlb and total Chl increased and a/b ratio decreased.Salinity stress increased F0 and decreased FM and Fv/Fm and damaged photosystem II. The Na and Cl- ion contents were higher in roots than in shoots and leaves in all three cultivars. In ‘Peyvas’ and ‘Shahanjir’ cultivars at 8 dS/m salinity the Na concentration was higher in leaves than in shoots and roots.. Efficacy of Na and Cl- exclusion mechanisms in roots differed among cultivars and it was most effective in ‘Sabz’. K concentration in leaves and roots of Shahanjir and Peyvas cultivars decreased by increasing salinity, but did not change in ‘Sabz’. Kﳖ ratio reduced under salinity conditions in all studied cultivars. Salinity stress tolerance among fig cultivars on the basis of growth factors and Na and K exclusion mechanisms was in the following order: ‘Sabz’> ‘Peyvas’> ‘Shahanjir’.