Nazimah Maqbool

The mitigating role of salicylic acid in growth, yield and various yield parameters in barley (Hordeum vulgare), genotypes viz., Jau-83 and Jau-87 under cadmium induced stress was studied. The pot study was carried out in the wire house, University of Sargodha, Lyallpur Campus, Faisalabad. Two (0 and 500 µM) levels of Cd metal and three (0.1, 0.5 0.9 mM) levels of salicylic acid alone and in combinations were applied directly in river sand medium. The experiment was designed as Completely Randomized (CRD), with factorial arrangement. Results revealed a marked reduction in shoot and root length, fresh and dry biomass, number of leaves and total leaf area and shoot root ratio under cadmium stress and increased with salicylic acid, but all the three level of SA behaved differently. Maximum increase in growth parameters were noted at 0.5 mM SA compared to 0.1 and 0.9 mM in both the barley genotypes. Although both genotypes statistically behaved similarly, Jau-83 behaved better than Jau-87. The results of yield provided drastic effect of Cd metal on all the recorded yield and yield parameters. The addition of salicylic acid alone in the irrigation medium increased the yield parameters. The results noted about the mitigating effect of salicylic acid under Cd stress exhibited an increase in yield parameters but the increase was less at low and high level of SA than 0.5 mM. SA suppressed the effect of cadmium induced stress and showed increase in growth and yield and yield parameters when applied exogenously through rooting. Results showed presence of SA in the irrigation medium containing cadmium metal mitigated the toxic effect of cadmium.

Heavy metal pollution is a stern global environmental challenge due to its long-term persistence in the environment and bioaccumulating nature. The vehicular emanations having traces of various heavy metals result in contamination of roadside plants and soil. A comparative investigation has been planned between olive varieties Arlik and Gemlik, collected from two sites; roadside and farmland Kallar Kahar. The potential for heavy metal accumulation was explored by comparing the morphological, physiological, biochemical, and antioxidant responses of both varieties from two different sites. Soil and mature olive leaves were sampled, labeled, and brought to the Botany Lab, at the GC Women’s University of Faisalabad, for further analysis. The sampling was completely randomized with three replications. The roadside soil showed a high concentration of Pb, Cd, Ni, and Zn and low concentrations of Na and K in comparison to farmland soil. The findings depicted that both Arlik and Gemlik olives experienced high metal stress under roadside conditions. Roadside olive varieties had smaller leaf areas, high fresh and dry weights, fewer amounts of chlorophyll A and B, total chlorophyll and carotenoids, total soluble sugars, proteins, and total free amino acids as compared to farmland olives. However, phenolics, MDA, anthocyanin, and proline antioxidants were greater under roadside stressed conditions. The concentrations of Ni, Pb, Cd, and Zn heavy metals and BAF were higher in both varieties of olive collected from the roadside as compared to farmland. The comparison among varieties showed that Arlik performed far better than Gemlik at both sites.