SALT STRESS

This study was carried out to examine the effect of salt stress on germination and seedling growth of Jute’s mallow (Corchorus olitorius L.) between two landraces (Ondo & NIHORT Research Institute). Several parameters were measured, including germination percentage, shoot length, number of branches, leaf area, number of leaves, stem girth, internode length and leaf loss for eight days to day fifty-six. The experimental treatments included various concentrations of Nacl; 10g/L(Z), 5g/L(Y), 2g/L(X), 0.2g/L(W) and the control (V). Germination was observed on the eight day for V,W,X with W having the highest germination percentage (86.6±1.15%), followed by V(70.00±1.00%). Treatment X recorded moderate germination (40.00±1.00% ), while treatment Y and Z had no germination. Low concentrations of salt (V,W and X) stimulated germination in Corchorus olitorius L.. Shoot length and number of branches were significantly higher in W (6.50±1.00, 2.00±3.46) by day 21, performing better than other treatments. The number of leaves and stem girth were also higher in W(1.67±2.89, 6.33±0.57), while X, Y and Z had no number of leaves and stem girth. W recorded the highest leaf area (9.06±15.68, 30.25±2.36). Analysis of variance (ANOVA) showed that there was no significant difference between W, control and other treatments for all parameters. The results suggest that W (with moderate salinity) enhanced germination and growth, whereas higher salinity (Y and Z) inhibited germination and growth, indicating an adverse effect of salinity stress on Corchorus olitorius L. physiology

Salt stress is an abiotic factor which poses significant threat to plant growth and productivity. A variety of plants are sensitive to salinity, one of which, is Corchorus olitorius. This study investigated the effect of salt stress on the germination, seedling growth, and physiological responses of Corchorus olitorius seeds collected from Benin (Landrace B) and National Horticultural Research Institute (NIHORT) designated as Landraces C. This experiment was conducted to determine how different concentrations of sodium chloride (NaCl) influenced germination percentage and the various growth parameters namely shoot height, number of leaves, leaf area, stem girth, number of branches, internode length, and leaf loss. The seeds were subjected to five treatments including control (5 ppm NaCl solution) and other varying salt concentrations (200 ppm, 2000 ppm, 5000 ppm, and 10000 ppm). Data collected were subjected to Analysis of Variance (ANOVA) to determine the level significance of the treatments. The results revealed significant differences in the parameters investigated. Increasing salinity levels significantly reduced germination rate, shoot elongation, and overall seedling establishment. The treatments with concentrations below 2000ppm recorded the highest mean values for germination percentage and growth parameters, while the treatments with the highest concentration of salt exhibited severe inhibitory effects leading to reduced germination rate, stunted growth, and poor seedling development. These findings demonstrated that C. olitorius is sensitive to high salinity levels, and salt stress adversely affects its early growth stages. It also reveals that C. olitorius seeds from Benin city were more sensitive to salt stress compared to C. olitorius seeds from NIHORT as higher germination percentage and growth were observed in landrace C.