Effects of varying concentrations of different salts on mineral composition of leaves and roots of three pomegranate (Punica granatum L.) cultivars

The present investigation assesses the behavior of three pomegranate cultivars (Punica granatum L.) (Wonderful', 'Ermioni' and 'Grenada') under increased concentrations of three salts (NaCl, KCl and K2SO4) after 150 days of growth in vivo conditions. The aim of this research was to study the nutrient accumulation and distribution in leaves and roots and its effects on total chlorophyll (a + b), carotenoids, photosynthetic rate and stomatal conductance of leaves. In general, high salt supply of KCl and K2SO4 led to significant decline in Ca and Mg concentration in leaves in all cultivars. 'Grenada' found with the highest concentration of Mn in leaves under all salt treatments. Regarding the roots, 'Wonderful' had the highest Mg concentration at 25, 50 and 75 mM of KCl and K2SO4, while 'Ermioni' had the maximum Ca concentration in roots. Chlorophyll concentration was reduced by the effect of KCl and K2SO4 salts in all cultivars. Furthermore, K2SO4 salt significantly reduced carotenoid concentration in leaves in all cultivars, especially 'Wonderful' showed 63.36 % reduction. 'Grenada' had the lowest photosynthetic rate and K2SO4 salt exerted a significant effect in all cultivars. Regarding stomatal conductance, 'Ermioni' had the highest values with KCl and K2SO4 salt treatments, while 'Grenada' was the most affected cultivar by all salts and at all concentrations. Our findings show the considerable potential of exploiting saline soils to obtain pomegranate plants with higher level of salt tolerance. Furthermore, our results suggest that 'Wonderful' and 'Ermioni' pomegranate cultivars may be cultivated also under marginal saline conditions.

Automated summary

This study evaluated the behavior of three pomegranate cultivars under increased salt concentrations, showing diverse responses in nutrient accumulation, chlorophyll and carotenoid concentrations, photosynthetic rate and stomatal conductance. 'Wonderful' and 'Ermioni' cultivars exhibited higher salt tolerance potential and could be cultivated under marginal saline conditions.