ASSOCIATION OF FRANKLINIELLA-FUSCA AND 3 WINTER WEEDS WITH TOMATO SPOTTED WILT VIRUS IN LOUISIANA

Random surveys of three common winter weed species using the enzyme-li nked immunosorbent assay (ELISA) and vector transmission studies demon strated that tomato spotted wilt tospovirus (TSWV) overwinters in Loui siana. Natural TSWV infection in Ranunculus sardous, Lactuca floridana , and Sonchus asper was detected by ELISA during the winter months and prior to spring vegetable production periods. Recovery of thrips from R. sardous, L. floridana, and S. asper washings yielded all developme ntal stages of Frankliniella fusca during the winter and spring. Ranun culus sardous appeared to be the species most often associated with na tural TSWV infection and thrips during the winter and prior to spring production periods. Frankliniella fusca adults collected from Ranuncul us spp. from three areas transmitted TSWV to tomato. Other TSWV-vector ing thrips species known to occur in Louisiana were not detected in as sociation with the weed species studied during the winter and spring m onths. Results of this study suggest that F. fusca is an important vec tor of TSWV in Louisiana.