Effect of Light Intensity and Salicylic Acid Interaction on Some Physiological Characteristics, Yield and Fruit Quality of Tomato (Solanum lycopersicum)

Light intensity is one of the most important environmental factors affecting the growth, yield and quality of fruits and vegetables. Salicylic Acid (SA) alleviates the negative effect of high and low light intensity. In order to evaluate the effect of interaction between light intensity and SA  on physiological properties, yield and fruit quality of tomato (Solanum lycopersicum L. cv. Super Beta F1), a split plot based on randomized complete block design experiment with three replications was carried out at Moghan College of Agriculture and Natural Resources located in Ardabil province, Iran in 2015. The treatment were included differentlight intensity levels (100, 75 and 50% light intensity) and SA (0 and 2 mM). Results revealed that the plant fresh and dry weight was decreased significantly with decreasing light intensity, especially without SA treatment. The leaf stomatal conductance and Fv/Fm ratio were increased with decreasing light intensity. The application of SA improved leaf stomatal conductance and Fv/Fm ratio. The application of SA caused increase in truss number and fruit number per truss under different light intensity levels. Tomato yield in full light intensity treatment and treated with SA was 116% higher than tomatoes yield grown in 50% light intensity and without treatment with SA. The highest and lowest value of total soluble solid, fruit firmness, EC and pH of fruit juice were obtained in full light intensity and 50% light intensity, respectively. In general, it is concluded that tomatoes grown in full light intensity has better yield and quality. SA application improves the quantitative and qualitative properties of tomato in different light intensities.