Biochemical properties of several genetic resources of the national tomato germplasm

Abstract

The tomato (Lycopersicon esculentum Mill.) is a self-pollinated diploid species with twelve pairs of chromosomes (2n = 24). It belongs to the Solanaceae family, along with other frugally important crops such as pepper, eggplant, and potato. Tomatoes are a rich source of vitamins and minerals (Ca, P, and Fe) and are strong antioxidants against cancer and heart disease. It is a leading vegetable crop in our republic and is widely cultivated in open and protected soils. Due to the biologically active substances and essential amino acids contained in the fruit, it is used in the daily diet of people throughout the year in fresh and “processing” form. The tomato plays an important role in the prevention of diseases in humans, and many varieties and hybrids belonging to its different varieties are currently being created by breeders. In our republic, tomato selection work started more than 90 years ago. Various cultivated varieties were created, which are widely cultivated by farmers. During the creation of the variety, great attention was paid to their taste and quality characteristics. The created varieties are of national value, and it is important to preserve them for future generations as well as for cultivation and selection purposes. Given the impact of climate change and varying environmental conditions on the biochemical indicators of tomato fruits, we performed these studies to get more accurate data on the fruits of different varieties of tomatoes under genotype x environment and genotype x year cultivation conditions.Objective: To evaluate the efficiency of several genetic resources of the national tomato germplasm in terms of the content of bioactive components and qualitative parameters (dry matter, sugars, acidity, vitamin C, B group vitamins.) in tomato fruits.Methods:Experiments were carried out at v. Darakert, Ararat Marz, Republic of Armenia, in 2021–2022. A block-randomized method was used to set up the experiment in four replications. Experiments were conducted on various genetic resources of the national tomato, including Fresh, “Processing”, Cherry, and Datterini varieties. The study examined bioactive compounds, dry matter, and total sugars in biologically ripened tomato fruits. Ascorbic acid was determined through titration, and B vitamins were quantified using spectrophotometric analysis on a Cary 60 UV-Vis spectrophotometer. The content of vitamin B was calculated using a calibration graph.Results: The study revealed that tomato fruits contain high levels of dry matter, sugars, acidity, vitamin C, and B group vitamins, with pantothenic acid, nicotinic acid, and inositol being predominant.Conclusion:Several genetic resources of national tomato: Yerevani 14, Noviy Anahit 19, Haykakan shtambovi 152, Masisi 202, Zvartnots, Noy (fresh tomato varieties), Renesans, Marine (“processing” tomato varieties), Zhanna, Rubina, Zeytun (cherry and datterini tomato varieties) have high levels of dry matter, sugars, acidity, vitamin C, B group vitamins and can be used as functional foods. Keywords: tomato, dry matter, sugars, acidity, vitamin C, B group vitamin