NaCl Acclimation Enhances Salt Stress Tolerance in Huckleberry (Solanum scabrum Mill.) Plants

Abstract

This study was carried out to assess the growth and physiological response of huckleberry (Solanum Scabrum Mill) to salt stress following acclimation with NaCl in Kumba, Cameroon. To achieve this, 1-month old seedlings were transplanted in 10-L pots and subjected to control (non-acclimated, no NaCl), acclimated (5 and 10 mM NaCl) and acclimation/salinity (5 + 75 mM and 10 + 75 mM NaCl). The following parameters were measured, growth (biomass, relative growth rate (RGR), number of leaves, and leaf area), physiological parameters (leaf thickness, and water use efficiency, WUE), and yield (shoot fresh mass). Salt stress significantly reduced the total fresh weight of non-acclimatized plants (T1) by 24 % relative to controls. However, acclimation significantly improved the growth of the plants under salt stress with T4 (acclimation with 5 mM NaCl), having more enhanced growth (52% increase, from control plants). Similarly the dry mass was also more significantly increased in acclimatized than in non-acclimatized plants, with T4 having the highest increase (72% increase, when compared with control plants). The total leaf area under salt stress was more significantly enhanced by acclimation with 5 mM NaCl (51% increase from control), while the RGR was significantly increased by acclimation under saline and non-saline conditions. The WUE was significantly elevated in acclimated plants under salt stress in T4 (46% from controls) than in the other treatments. Leaf thickness was significantly enhanced in both acclimated and non-acclimatized plants, being highest under the T4 treatment. WUE and Leaf thickness were strongly correlated with all growth parameters except number of leaves. Taken together, these results clearly indicate that acclimation with low NaCl, especially 5 mM NaCl imparts salt stress tolerance in huckleberry. Hence acclimation with 5 mM NaCl is recommended for use in the cultivation of huckleberry on saline soils.