BEHAVIOUR OF DIFFERENT PROCESSING TOMATO CULTIVARS GROWN ORGANICALLY IN TUNISIA

Organic agriculture provides great commercial opportunities on both national and international markets. In fact, the demand of organic products is increasing and is closely linked to increased awareness of the impact of foods on the well being and health of people. Organic processing tomato culture is relatively recent in Tunisia and little is known about organic cultivation practices. The choice of appropriate cultivars adapted to the organic environment is one of the most important factors of success for the cultivation of tomatoes. In this context, the present study involves nine common cultivars of processing tomatoes grown organically and evaluated on the basis of various agronomic and quality characteristics. The hybrids Amico, Philadelphia, Sun 6200, Firenze, Red Spring, Hypeel 303 and Perfectpeel and the open pollinated Rio Grande and Justar were used. The results show that the total yields of the different varieties were lower than those usually recorded under conventional farming and were not significantly different between cultivars. Significant differences were however recorded in unmarketable yields; significant differences between the cultivars were recorded in fruit quality characteristics (colour, °Brix, pH, acidity, lycopene and phenolic compounds). Under the trial conditions, the global evaluation of the cultivars, based on all the parameters measured and observed, shows that the cultivars Rio Grande and Firenze distinguished themselves for dual-purpose use (fresh and processing) and Perfectpeel strictly for processing.