Bull. Spec. CORESTA Congress, Lisbon, 2000, p. 62, AP12

Suppression of Tomato Spotted Wilt Virus with acibenzolar-S-methyl and imidacloprid in flue-cured tobacco

University of Georgia, Coastal Plain Experimental Station, Tifton, GA, USA
Tomato Spotted Wilt Virus (TSWV) has become the major constraint in tobacco production in Georgia. No single control measure has been found effective in minimizing the severity or incidence of the disease. Foliar applications of acidobenzolar-S-methyl (Actigard) were tested in four replicated field trials alone and in combination with imidacloprid (Admire and Provado) for their efficacy on incidence of TSWV in tobacco. Actigard used alone, applied as a foliar in the float house at 2 g a.i./7K plants and applied in the field four times at 25 g a.i./A, and in combination with imidacloprid, applied in the float house at 67.2 g a.i./7K plants and applied in the field four times at 21.5 g a.i./7K plants, significantly reduced incidence of TSWV in all four trials. The number of Enzyme-Linked Immunoabsorbent Assay (ELISA) positive plants for TSWV were significantly reduced in three of the four trials by the Actigard treatments alone, and in combination with the imidacloprid treatments. The imidacloprid treatments alone reduced the number of ELISA positive plants only in one of the four locations. The use of plant defense activators such as Actigard, alone and with the insecticide imidacloprid, shows promise as an effective management tool for TSWV. Further research is being conducted on evaluating rate and timing scenarios to most effectively manage TSWV incidence.