Genotypic, Temporal, and Tissue-type Effects on the Incidence of Tomato spotted wilt virus in Peanut (Arachis hypogaea L.)

Spotted wilt, caused by Tomato spotted wilt virus (TSWV), is one of the major diseases affecting peanut production in the southeastern United States. Growers use integrated disease management to control spotted wilt; however, disease resistance of a cultivar is the most important factor for managing this disease. This research evaluated genotypic, temporal, and tissue-type effects on the incidence of TSWV on each of four peanut cultivars. Four different types of tissues (leaf, root crown, old leaf and young leaf) were collected from each of four peanut cultivars (Florida-EPTM ‘113’, Florida-07, Georgia Green and Georgia Valencia) at five time points during the growing season. Immunoassays were conducted to detect viral presence. The incidence of TSWV infection increased over time during the growing season. Root crown tissue had higher infection than other types of tissue. Florida-EPTM ‘113’ had the lowest infection incidence. Compared to Florida-EPTM ‘113’, Florida-07 was seven times more likely to be infected by TSWV, while Georgia Green and Georgia Valencia possessed even higher probability, 18 times and 21 times higher, respectively. Florida-EPTM ‘113’ had significantly reduced TSWV infection likely due to slowing movement of the virus throughout the plant.