The Effect of Spectral Composition of Light on Physiological and Biochemical Characteristics of Tomatoes

Abstract

The effect of white, blue and red light on the relative humidity of the leaves, as well as on the content of photosynthetic pigments, the activity of photosystem-2, the content of proteins and soluble carbohydrates in the leaves of tomato varieties were studied. Photosynthetic pigments were determined by the method of leaf homogenization, in 96% ethanol, with further centrifugation at 200 g. Measurements were conducted using a spectrophotometer at wavelengths of 665, 649 and 440.5 nm. The content of soluble sugars was determined at wavelengths of 630-570 nm by the accelerated bichromate method. The protein content was determined on a spectrophotometer SP 2000, at wavelengths of 230 and 260 nm. Studies have shown that during the influence of red light, there is a slight decrease in the protein content, an increase in the content of photosynthetic pigments and soluble carbohydrates in all varieties of tomatoes grown in red light. Unlike red light, blue light stimulated the synthesis of proteins in leaves. Red light promotes the synthesis and accumulation of carbohydrates, while blue light encourages the synthesis of proteins in tomato leaves.