Micronutrient composition and quality characteristics of traditional tomato cultivars in southeast Spain

Several traditional tomato cultivars still survive in the orchards in southeastern Spain, which are highly esteemed due to their excellent quality. However, modem tomato hybrid varieties used in intensive agriculture mean that these types of local cultivars are being gradually phased out. This study was conducted to characterize the diversity of tomato micronutrient composition and fruit quality parameters of several traditional cultivars. The experiment was carried out under field conditions using traditional cultivars of the Muchamiel and De la Pera type and commercial F1 hybrids. Micronutrient fruit concentration (Fe, Cu, Mn, and Zn) was determined by atomic absorption spectroscopy. Fruit quality parameters analyzed were titratable acidity, soluble solid content, and color parameters. Strong differences have been found among the analyzed cultivars, both in terms of micronutrients and also quality parameters, suggesting that there are considerable levels of genetic diversity. Not a single superior variety could be identified, because it would depend on type of use, consumers' and growers' preferences. These traditional cultivars are frequently consumed at the breaker maturity stage, but we have found low differences between red and breaker fruits regarding micronutrient concentrations. Through relatively simple chemical analyses, we have detected significant differences among tomato genotypes that we are still not able to detect with molecular tools. Cultivars could be clearly differentiated on the basis of a multivariate data analysis of selected fruit parameters. This knowledge could aid in the efficient conservation of an important part of the agricultural biodiversity in southeastern of Spain. These results are also potentially useful for tomato breeders working on the development of new varieties.