Tospovirus on ornamental crops in La Plata.

Tomato spotted wilt virus (TSWV) has been causing diseases of well known economic importance in horticultural crops in Argentina for decades. In 1995 it affected some of the most widely spread chrysantemum cultivars. The Tospovirus genus, of which TSWV is a species, was first defined at the beginning of the 90s, so a general survey of this group of viruses affecting ornamental crops is neccessary to document symptoms associated with the infection and to establish appropriate control measures. 370 samples of 22 species from La Plata district were analized using biological and immunoenzimatic techniques. Two Tospovirus have been found: tomato spotted wilt virus (TSWV) on Aster ericoides, Aphelandra sp, Dendranthema morifolium, var. Dignity, Palisade and Southing Sun, Eustoma sp and Gerbera sp, and tomato chlorotic spot virus (TCSV) on Eustoma sp. This host was previously unreported for both viruses. Impatiens necrotic spot virus (INSV), and groundnut ring spot virus (GRSV) were not found in any of the analized samples. Our results indicate that Tospoviruses have not had a quick spreading in ornamental crops, except for some chrysantemum cultivars. Nevertheless they constitute a potential threat as foreseen by similar situations in other countries of warm weather.

Key Words: Tospovirus, ornamentals, TSWV, TCSV