Details on tomato spotted wilt tospovirus in Israel
In Israel, tomato spotted wilt tospovirus (EPPO A2 quarantine pest) was found for the first time in 1992 (EPPO RS 94/007), shortly after the first appearance of its vector Frankliniella occidentalis in 1991. Studies were carried out to identify the main host plants, in ornamental and vegetable crops and also in weeds. Plants showing symptoms were collected from January 1992 to December 1996. By using inoculation to herbaceous indicators, ELISA, and electron microscopy, the following cultivated species were found to be infected by tomato spotted wilt tospovirus: Asclepias tuberosa, Aster sp., Brassica oleracea, Capsicum annuum, Celosia sp., Cestrum sp., Cucumis sativus, Cucurbita pepo, Eustoma rusellianum, Gerbera sp., Gloxinia sp., New Guinea impatiens, Lactuca sativa, Lycopersicon esculentum, Ocimum sp., Solanum melongena, Solanum tuberosum, Vinca sp. and Zinnia sp. In the major ornamental and vegetable growing regions of Israel, the following weeds were found infected: Sonchus oleraceus, Solanum nigrum, Conyza bonariensis, Portulaca oleracea, Silybum marianum, Cichorium pumilum. It is noted that the outbreak of tomato spotted wilt tospovirus in Israel is associated with large populations of F. occidentalis. However, despite the wide distribution of this insect, outbreaks of the disease are sporadic and limited.
Characterization studies were also carried out on the Israeli isolates. It was shown that all Israeli isolates obtained either from vegetable or ornamental crops are serologically identical (and are members of the tospovirus serogroup I, type I (BR-01 strain)).
In addition, seed transmission was investigated on tomato, pepper, Petunia and Celosia. Although the virus could be detected on the surface of seeds harvested from naturally infected plants, transmission of the virus to the progeny plants could not be obtained.
Sources
Antignus, Y.; Lapidot, M.; Ganaim, N.; Cohen, J.; Lachman, O.; Pearlsman, M.; Raccah, B.; Gera, A. (1997) Biological and molecular characterization of tomato spotted wilt tospovirus in Israel.
Phytoparasitica, 25(4), 319-330.