Weeds naturally infected by beet curly top geminivirus
Studies were carried out in the San Joaquin Valley in California (US), on the incidence of beet curly top geminivirus (EU annex II/A1) in weeds, from May 1993 to February 1995. A dot-blot hybridization technique was used to detect the virus. Results showed that the virus could be found in 14 different plant families (Amaranthaceae, Asteraceae, Boraginaceae, Brassicaceae, Chenopodiaceae, Convolvulaceae, Euphorbiaceae, Fabaceae, Geraniaceae, Malvaceae, Onagraceae, Polemoniaceae, Solanaceae, Zygophyllaceae). Beet curly top geminivirus has been found for the first time in Ambrosia acanthicarpa, Helianthus annuus, Epilobium ciliatum, Amsinckia menziesii, Tribulus terrestris and a Gilia sp. Naturally infected weeds generally showed no symptoms. Infection rates of weeds varied from 2 to 11 %, and are lower than in sugar beet or tomatoe. The collection of infected plants throughout the year suggests that the virus can overwinter in plants and does not need to be reintroduced by vectors (Circulifer tenellus) each year in this region.
Sources
Creamer, R.; Luque-Williams, M.; Howo, M. (1996) Epidemiology and incidence of beet curly top geminivirus in naturally infected weed hosts.
Plant Disease, 80(5), 533-535.