Influence of planting date and insecticide treatment on incidence of tomato spotted wilt virus in burley and flue-cured tobaccos in North Carolina

Tomato spotted wilt virus (TSWV) is an economically significant disease of tobacco and other crops. Anecdotal evidence in North Carolina suggests that the incidence and severity of TSWV are greater in burley tobacco varieties compared to the flue-cured varieties traditionally planted in the coastal plain and piedmont. Field studies were conducted at the Lower Coastal Plain Research Station in eastern North Carolina to evaluate the effects of tobacco type (burley or flue-cured) planting date (early or late) and treatment with the soil applied, TSWV-suppressive insecticide imidacloprid, on the incidence of TSWV transmitted by feral thrips populations. Through both planting dates and with or without imidacloprid, burley tobacco had approximately twice the incidence of TSWV than flue-cured tobacco under the same conditions. We are currently conducting research to elucidate the underlying causes of this higher incidence.