Foliar Arginine Application Improves Tomato Plant Growth, Yield, and Fruit Quality
Abstract Tomatoes are important for human health, and there is an urgent need to increase tomato yield and quality worldwide. Arginine is proven to be beneficial for crop storage quality and stress resistance in plants; however, its effects on tomato production and quality have not been fully investigated. This study demonstrated the effects of spray application of arginine on tomato growth, yield, and quality. Arginine treatment significantly increased the nitrogen concentration in the aboveground tomato plant parts and fruit, net photosynthetic rate, stem diameter, dry mass weight, and root activity. It is suggested that increased nitrogen accumulation following arginine application is mainly due to arginine uptake as organic nitrogen, higher expression of the LeNRT1.1 gene, and increased root activity. The increased nitrogen levels improved photosynthesis and promoted tomato plant growth. Moreover, foliar arginine application enhanced fruit size, weight, and yield. Arginine treatment had a positive effect on tomato quality as indicated by the concentrations of lycopene, vitamin C, soluble solid, soluble sugar, and titratable acids, and the sugar-acid ratio. Arginine application has potential to improve tomato production by regulating plant development and enhancing fruit yield and quality.