Lycopene and Processing Tomato in Navarre: Influence of Vegetable Material

Lycopene is a natural component of tomatoes characterised by its high colouring capacity and its biological and antioxidant activity. Different studies have shown that the lycopene content in the tomato depends fundamentally on genetic (vegetable material) and environmental factors (i.e. mineral nutrient supply, soil conditions, crop seasons, etc.) and also on the degree of ripeness. The aim of this study was to analyse the influence of genotype on production and on different parameters of quality, principally colour and lycopene content of the processing tomato in Navarre. The trials were conducted from 2010 to 2011 in the experimental farm of the Instituto Navarro de Tecnologias e Infraestructuras Agroalimentarias (INTIA) in Cadreita's locality, in the south of Navarre. Six cultivars of processing tomato were trialed in the field, 4 of which carried alleles whose expression cause an increase in the concentration of lycopene in the fruit; and the other two were used as controls. Fruit yield was measured as total biomass production, commercial marketable yield, and average fruit weight. The fruit quality parameters measured were: pH, degrees Brix, Hunter-scale color (a/b) and lycopene content. The most productive cultivars ('H-9036', 'H-9661' and 'H-9997') contained the lowest concentration of lycopene in the fruit. Cultivars with high lycopene content exceeded the two controls in red color purity, measured as a/b. 'Agraz 5' and 'ISI-24424' cultivars had the highest content of lycopene. 'H-9997' showed a slightly higher concentration of this antioxidant than the controls. In this study, the genetic influence was crucial to the content of lycopene in the fruit, but there are the traditional cultivars that farmers are commonly growing which have more intensity color.