Thrips-transmitted Tomato spotted wilt (TSW) virus (Family Bunyaviridae Genus Tospovirus) is an important problem in tomato in the southeastern United States. Tobacco thrips, Frankliniella fusca (Hinds), and western flower thrips, Frankliniella occidentalis (Pergande), (Thysanoptera:Thripidae) are the known major vectors of TSW virus in Georgia; however, the temporal relationship of thrips to TSW disease incidence in tomato is not clear. Field studies were conducted in 2005 and 2006 specifically to compare thrips population dynamics to disease incidence in untreated tomato fields. Populations of F. fusca were observed to increase approximately 3 wks prior to increased TSW incidence and correlated positively with TSW when considering this delay. Populations of F. occidentalis positively correlated with TSW occurrence in 2005, but not in 2006. Additionally, tomato fruit yield decreased greater in plants with early TSW symptoms than in plants that developed symptoms later in the season. Both results suggest early-season thrips management targeted at F. fusca during the early-growth stages of tomato could help to reduce the risk of yield loss in tomato due to this disease.
tomato spotted wilt virus