Submitted to: Pest Alert
Publication Type: Other
Publication Acceptance Date: 4/8/2003
Publication Date: N/A
Interpretive Summary: This is the first report of tomato spotted wilt virus infection of a common weed in southeast Florida. It includes a description of foliar symptoms. The diagnostic methods used to confirm the identity of tomato spotted wilt virus are also described and several control measures are outlined. This virus can cause serious economic losses in this and other regions of vegetable and ornamental production. This report continues a collaborative virology research effort between ARS and the Florida Department of Agriculture and Consumer Services, Division of Plant Industry and provides a timely account of the current tomato spotted wilt virus infection in this common weed to growers, Extension personnel and state and Federal vegetable scientists.
Technical Abstract: Symptoms consistent with a virus infection were observed on American black nightshade (Solanum americanum) plants in a vegetable field in southeast Florida in March 2003. A chlorotic mosaic was present on leaves, frequently accompanied by slight distortion. Symptoms were generally most noticeable on new growth. The presence of a tospovirus was confirmed by symptoms induced on indicator host plants and by inclusion body morphology. Serological tests (ELISA) were used to identify the tospovirus as tomato spotted wilt virus (TSWV). This is the first report of TSWV infection of S. americanum in Florida although several other viruses have previously been reported to infect this weed. TSWV infects tomatoes, peppers and a wide range of other vegetable, agronomic and ornamental crops in Florida. The Solanaceae and Compositae families contain the largest numbers of susceptible species. TSWV is transmitted in the field almost exclusively by several species of thrips.