Ameliorating effects of hydrogen sulfide on growth, physiological and biochemical characteristics of eggplant seedlings under salt stress

In this study, the effects of exogenous hydrogen sulfide (H2S) treatments on eggplant seedlings were examined under salt stress. This study was a pot study carried out under controlled greenhouse conditions with three salt levels (0, 50 and 100 mM NaCl) and four H2S doses (0, 25, 50 and 100 mu M NaHS). Plant growth parameters, chlorophyll content, membrane permeability (MP), leaf relative water content (LWRC), photosynthetic properties, hydrogen peroxide (H2O2), proline, malondialdehyde (MDA), sucrose, and antioxidant enzymes (catalase (CAT) and superoxide dismutase (SOD)) activity, abscisic acid (ABA) and minerals content of eggplant seedling were examined. Plant growth properties were decreased with salinity. However, H2S application alleviated the effect of salt stress on these parameters. Membrane permeability increased with salt stress, but was lower in H2S treatments than non-H2S treatment. Salt stress significantly decreased LWRC, stomatal conductance (gs), net photosynthetic rate (Pn), intercellular CO2 concentration (Ci), transpiration rate (Tr) and chlorophyll properties. With H2S treatments, these decreasing were lower. Hydrogen peroxide, MDA, proline and sucrose content increased compared to the control, but H2O2, MDA, proline and sucrose content of eggplant seedlings decreased with H2S treatment under salt stress. Furthermore, CAT and SOD increased with different salt levels. However, CAT and SOD activity decreased with H2S treatments under salt stress. ABA content increased significantly with salinity, but ABA content decreased with H2S treatments under salt stress conditions. Similarly, the mineral content of leaf and root of eggplant seedlings were decreased under salt stress (except for Na and Cl), the decrease of mineral content was lower with H2S treatments. Effect in alleviating of the H2S on salt stress damage can explained by regulation of enzyme activity and mineral uptake, low level of ABA and the minimization of reactive oxygen species (ROS) damage by accumulation of osmolytes. Published by Elsevier B.V. on behalf of SAAB.