University of Florida tomato breeding accomplishments and future directions

Fresh market tomato (Lycopersicon esculentum Mill.) breeding began at the Univ. of Florida in 1922. Contributions from me program have been a key reason why tomato is the most valuable vegetable in Florida, and that Florida is by far the leading state in fresh market tomato production in the USA. At present, 44 cultivars/breeding lines have been released, of which 41 are open-pollinated and three are hybrids. Five additional releases are planned for 1999. Seed companies did not have significant involvement in tomato breeding for Florida until the 1970's, when hybrids began to take over the market. Thus, much of the germplasm used in present-day Florida varieties and elsewhere in me world traces to improvements derived from the UF program. There have been nine scientists at the Univ. of Florida with a primary responsibility to breed tomatoes, although numerous cooperators have also made significant contributions. Some of the significant advancements were: the eradication of nailhead rust (Alternaria tomato (Cke.) Weber) in the 1930's by the use of resistant cultivars; the combination of more than five disease resistances in 'Manalucie' in 1953; the first Fusarium wilt [Fusarium oxysporum Schlecht. f. sp. lycopersici (Sacc.) Snyder & Hansen] race f resistant (I-2 gene) cultivar 'Walter' in 1969; the development of cultivars with high levels of fruit firmness and jointless pedicels in the 1970's; the development of commercially acceptable heat-tolerance with the release of 'Solar Set' in 1989; the discovery of resistance to Fusarium wilt race 3 (I-3 gene) in the 1980's; and the release of breeding lines with I-3 in 1994. The release of the miniature dwarf 'Micro-Tom' in 1989 provided a model system for modern mutagenesis techniques for plants with fleshy fruit. Of possible importance in the future are the development of: high lycopene log gene) hybrid cultivars with superior internal color and flavor; germplasm with resistance to the three races of bacterial spot (Xanthomonas campestris pv. vesicatoria (Doidge) Dye) that infect tomato; and the development of improved germplasm with resistance to the gemini viruses tomato mottle virus (ToMoV) and, especially, tomato yellow leaf curl virus (TYLCV). The impact of the Univ, of Florida tomato breeding program has been important not only to the livelihood of Florida growers but also to tomato breeding programs around the world.