Target spot of tomato, caused by the fungus Corynespora cassiicola (Berk. & Curt.) Wei., is one of the most serious foliar diseases of tomato (Lycopersicon esculentum Mill.) in the winter tomato production areas of Florida,USA. Losses in marketable yield of 11 800 kg/ha have been recorded in test plots when target spot has not been adequately controlled (PERNEZNY et al. 1996). Leaf symptoms of target spot include necrotic lesions with light-brown centers. These lesions often coalesce and result in large blighted areas on leaves that lead to premature defoliation. Perhaps the most serious aspect of target spot is the development of lesions on fruit. These fruit symptoms range from small, brown, sunken flecks to large, deeply pitted areas that render the fruit totally unsuitable for market. Fruit are often predisposed to target
spot by injury from sand and soil particles impinging the fruit surfaces during stormy weather (VOLIN et al.1989). Host-plant resistance and cultural methods have not been effective strategies for management of this disease (BLAZQUEZ 1977). Foliar sprays with fungicides have offered the best alternative for Florida growers to date (JONES & JONES 1984). The objective of this research was to investigate the management of target spot with newer generation fungicides, systemic acquired resistance (SAR) activators, and a biocontrol agent.