Synergistic effects of biochar and halotolerant on wheat growth and their potential to reclaim saline-sodic soil

The problem of soil salinization is one of the major threats to agricultural productivity worldwide. To address this issue, a wide range of adaptations and mitigation strategies are needed. Biochar, an activated carbon soil conditioner can help in alleviating the deleterious effects of salinity. The current research aimed at evaluating the effectiveness of biochar in the redemption of saline-sodic soil, as well as improving the growth and yield of wheat when used in conjunction with halotolerant plant growth promoting bacteria (PGPBs). For this purpose two experiments were established as incubation and greenhouse. Firstly, high salt tolerant bacterial strains to be used in the study were isolated and screened. Then an incubation study was established for 3.5 months to monitor the biochar and halotolerant PGPBs effect on chemical properties of saline sodic soil. Cotton stalk and Olive pulp biochar were used for this purpose together with their feedstocks as positive controls. In accordance with the results each biochar type, whether applied alone or together with halotolerant was effective in improving the overall quality of degraded soil. Soil organic matter, (OM), cation exchange capacity (CEC), total nitrogen (TN) and exchangeable cations (calcium (Ca+2), magnesium (Mg+2) and potassium (K+) were significantly increased while soil sodium (Na+) content, sodium adsorption ratio (SAR) and exchangeable sodium percentage (ESP) were greatly reduced. Higher the application rate better was the result. Results of greenhouse experiment indicated that growth and yield of wheat was favorably increased with biochar application and effect was more prominent for the co-application of biochar with halotolerant. The post harvest soil analysis revealed a significant reduction in soil pH and EC in comparison to the control. In light of the obtained results, co-application of biochar and halotolerant could be a sensible approach to reclaim the saline-sodic soils, thereby making the conditions suitable for plant growth under salinity stress.