Biochar coupled with KNO(3) improves tomato yield and quality by modulating photosynthesis, nitrogen metabolism and antioxidant defense.

Biochar combined with KNO3 enhances tomato yield by 35.2% and fruit quality under drought stress through improved physiological and metabolic responses.

• Why it matters: Drought severely limits tomato production worldwide, and understanding how to mitigate its effects is crucial for food security and sustainable agriculture.
• What they did: The study applied biochar and varying KNO3 concentrations to drought-stressed tomatoes, measuring physiological parameters, gene expression, and fruit quality over multiple experiments.
• The result: The combined treatment increased water retention, photosynthesis, antioxidant activity, and nitrogen metabolism, enabling significant yield and quality improvements, especially with biochar and 50 mmol L-1 KNO3.