Florida tomato growers have been managing tomato mottle mosaic virus (TMoV), vectored by the silverleaf whitefly (Bemesia argentifolia) since 1990. Bean growers in the Dade and Palm Beach County area have tried to control bean golden mosaic virus (BGMV) since it entered the area with Hurricane Andrew in 1992. During Summer 1997, tomato yellow leaf curl virus (TYLCV) was found in summer-grown tomatoes in Dade County. In Fall 1997, tomato growers were notified of the new problem and attended a workshop discussing the rigorous control that would be needed to minimize its effects. They instituted scouting and roguing programs in conjunction with appropriate pest management procedures. Dade bean growers worked with the Florida Fruit & Vegetable Assn. to obtain a Section 18 for imidacloprid. Bean and tomato growers learned about gemini viruses affecting both crops and the distribution of these viruses in the Americas in the fall of 1998. Bean growers have also learned how to use imidacloprid in late 1998/early 1999. Extension methods used and their success will also be discussed.
Mary Lamberts and Jane Polston
Roger L. Vallejo and Jane E. Polston
Cultured cotyledon and leaf pieces of five cultivars of Lycopersicon esculentum Mill. were tested in six culture media for their ability to produce shoots for transformation studies. The no. of tissue pieces with callus/total tissue pieces, quality of callus (size and vigor), no. of tissue pieces with shoots/total tissue pieces, and shoot quality (size and vigor) were measured. Cultivars tested were `Campbell 28', `Flora-Dade', `UC82b', and two breeding lines, Fla.7171 and Fla.7324. The six media used were Murashige and Skoog medium supplemented with six combinations of indole acetic acid (IAA) and cytokinins: A) 1 mg/l IAA + 1 mg/l kinetin, B) 0.5 mg/l IAA + 2 mg/l kinetin, C) 0.02 mg/l IAA + 1 mg/l zeatin, D) 0.2 mg/l IAA + 2 mg/l zestin, E) 1 mg/l IAA + 2.5 mg/l BAP (6-benzyl amino purine), and F) 0.2 mg/l IAA + 1 mg/l BAP. Standard procedures were followed for culturing 4 - 5 mm pieces of cotyledon and leaves. Callus and shoot regeneration were greater, less variable and faster, in cotyledon than in leaf pieces. Media C and F gave the highest rates of callus and shoot production, respectively, in cotyledon tissue. Medium E gave the highest rate for both callus and shoot production in leaf discs. The best rates of shoot production were achieved with cotyledon tissue from cultivar UC82b cultured on media C (85.3%) and F (77.2%).