Calcium and zinc mediated growth and physio-biochemical changes in mungbean grown under saline conditions

Salinity is a major abiotic factor adversely affecting plant productivity by reducing calcium (Ca) uptake due to strong antagonistic effects of sodium (Na) in the root regions. In calcareous soils, most of the essential nutrients precipitate in unavailable forms for plants. This study investigated the physiological and biochemical response of two mungbean varieties (salt-tolerant Mung-88 and salt-sensitive NM-28) supplemented foliarly with Ca and zinc (Zn) and their combination (Ca + Zn). An experiment in plastic pots (containing 5 kg washed river sand), with above indicated two mungbean varieties, foliar application of Ca (0.1%), Zn (0.1%) and their combination (Ca + Zn) along with control (with no foliar spray) based on a complete randomized design, was conducted under two levels of salinity (0 and 8.0 dS m(-1)). The results showed a significant effect of foliar application of Ca, Zn and their combination on chlorophyll (Chl) contents, gas exchange (photosynthetic activity), N, P, K and biomass attributes under both saline and normal conditions. The foliar application of Ca + Zn (0.1% each) was effective in increasing plant biomass by altering physiological and biochemical processes under saline conditions. The results achieved highlight the importance of Ca and Zn nutrition in salt-stress conditions.