Effects of exogenous and foliar applications of Brassinosteroid (BRs) and salt stress on the growth, yield and physiological parameters of Lycopersicon esculentum (Mill.)

Abstract

The germination response of Lycopersicon esculentum was studied on different salinity levels from control (non-saline), 0.2,0.4,0.6 and 0.8% NaCl solution. Seeds germinating under salt stress exhibited decrease in saline media as compared to respective control. Seeds germinating with salinity and brassinosteroid (applied exogenously through roots and as foliar spray, 0.25 and 0.5 ppm) exhibited promotion in control as compared to their respective saline media. Plants treated with different salts concentrations (60 and 100mM) NaCl exhibited reduction in plant height, root length, number of leaves, number of fruits and biomass as compared to control while brassinosteroid having concentrations of 0.25 and 0.5 ppm (applied through roots and as foliar spray) caused promotion in plant height, root length, number of leaves, number of fruits and biomass in saline and non saline media. Plants treated with different salts concentration of (60 and 100mM) NaCl exhibited increase in Relative water content, leaf water loss, electrolyte leakage, shoot/- root ratio, root/- weight ratio and leaf/- weight ratio at both NaCl concentrations (60 and 100 mM) as compared to control, while stem/- weight ratio showed reduction at both salinity levels as compared to control while brassinosteroid applied in roots and as a foliar spray at 0.25 and 0.5 ppm concentrations exhibited reduction in stem/- weight ratio at high NaCl level (100 mM) as compared to control.