Chloride modulates carbohydrate metabolism and ethylene synthesis in tomato fruits

Summary

SUMMARY Chloride ions (Cl−) play a unique role in enhancing crop fruit quality, particularly through their effects on carbohydrate metabolism, although the underlying mechanism remains unclear. We optimized the Cl− concentrations in tomato cultivation nutrient solutions via supplementation at varying levels and utilized an integrative approach combining biochemical assays, transcriptomics, and metabonomics to investigate how Cl− modulates sugar metabolism in tomato fruits. Treatment with 3–5 mm Cl− significantly improved plant biomass, photosynthesis, dry matter accumulation, and fruit quality without affecting yield or altering the dry matter distribution. Our findings indicate that Cl− increased starch and sucrose contents in fruits during the cell enlargement stage and elevated glucose,