Influence of biochar and chitosan on productivity of tomato under water-stress conditions

Adding biochar to the soil as an amendment might help it retain more water, which could increase crop yields.The experiment was conducted at Sher-e-Bangla Agricultural University, Dhaka, Bangladesh during January to April 2022 to determine the effects of chitosan and biochar on tomato plants under water stress in terms of productivity.In this experiment, three water regimes (i) at 80% of field capacity (FC), ii) at 60% of FC, and iii) at 40% of FC were used as treatments.Additionally, three drought mitigating agents were used: i) chitosan (200 L L -1 ha -1 ), ii) rice husk biochar (20 t/ha), and iii) biochar + chitosan.Biochar was used to transplant 25-day-old, uniform, healthy seedlings into plastic pots.Drought was imposed ten days after transplantation, lasting till flowering.Chitosan was applied using a hand sprayer ten days after implantation.The findings revealed that water stress significantly reduced tomato morphological, physiological, and biochemical properties while increasing pH.However, the effects of water stress on tomato plants were greatly mitigated by the use of biochar and chitosan.The number of leaves, chlorophyll content, days needed from transplanting to the first flowering, fruits per plant, weight of each individual fruit, yield per plant, pH, and titratable acidity content all significantly improved with the application of biochar and chitosan.Consequently, in terms of growth, yield, and biochemical parameters, the combination effect of chitosan and biochar appeared more effective.