Biochemical composition of tomato fruits of various colors

Abstract

Tomato (Lycopersicon esculentum Mill.) is an economically important and widely cultivated vegetable crop that is consumed both fresh and processed. The nutritional value of tomato fruits is related to the content of carotenoids, polyphenols, sugars, organic acids, minerals and vitamins. Currently, there is a growing interest in the qualitative and quantitative increase in the content of health-promoting compounds in tomato fruits. VIR Lycopersicon (Tourn.) Mill. genetic resources collection includes 7678 accessions of one cultivated and nine wild species, which in turn provides ample opportunities for searching for information on the variability of the content of biologically active substances and searching for sources with a high content of them in the gene pool. Our work presents the results of the study of 70 accessions of cultivated and wild tomato on the main biochemical characteristics: the content of dry matter, ascorbic acid, sugars, carotenoids, chlorophylls and anthocyanins. As the basis for the selection of accessions for the study, accessions with various colors of fruits, including new accessions with varying content of anthocyanin, were taken. As a result of this study, the amplitude of variability in the content of dry matter (3.72–8.88 and 9.62–11.33 %), sugars (1.50–5.65 and 2.20–2.70 %), ascorbic acid (12.40–35.56 and 23.62– 28.14 mg/100 g), titratable acidity (0.14–0.46 and 0.33–0.48 %), chlorophylls (0.14–5.11 and 2.95–4.57 mg/100 g), carotenoids (0.97–99.86 and 1.03–10.06 mg/100 g) and anthocyanins (3.00–588.86 and 84.31–152.71 mg/100 g) in the fruits of cultivated and wild tomatoes, respectively, was determined. We have determined correlations between the content of dry matter and monosaccharides (r = 0.40, p ≤ 0.05), total sugars (r = 0.37, p ≤ 0.05) and ascorbic acid (r = 0.32, p ≤ 0.05); the content of ascorbic acid and carotenoids (r = 0.25, p ≤ 0.05). A high dependence of the content of chlorophyll a and b among themselves (r = 0.89, p ≤ 0.05), as well as between the content of chlorophyll b and anthocyanins (r = 0.47, p ≤ 0.05), the content of β-carotene (r = 0.26, p ≤ 0.05) and the content of monosaccharides (r = –0.29, p ≤ 0.05) has been noted. We have identif ied tomato accessions with a high content of individual chemical substances, as well as with a complex of traits that can be used as sources in breeding for a high content of dry matter, sugars, ascorbic acid, pigments and anthocyanins.