Indagine sulla eco-epidemiologia di virus delle ortive in Provincia di Brindisi

Eco-epidemiological research of vegetables viruses in Brindisi Province Nearly 45% of Italy’s tomato production is fieldgrown in Apulia, Southern Italy and in this Region, the Brindisi Province is the second largest producer with an acreage of about 3500 ha. The crop is directed mostly to canning industry and has a high economic value. In 1997 and 1998 about 30% of the total tomato acreage in the Brindisi Province was stricken by massive outbreaks of virus diseases involving mainly Tomato spotted wilt virus (TSWV), Cucumber mosaic virus (CMV), Alfalfamosaic virus (AMV) and Potato virus Y (PVY). All these viruses caused appreciable economic that caused relinquishment of traditional tomato-growing areas, low quality of the commodities and a huge increase and often indiscriminate use of insecticides. TSWV epiphytotics were the most devastating with nearly 95% crop losses. This paper reports the results of a systematic survey whereby, over a 12-month period, the occurrence of TSWV, CMV, AMV and PVY was monitored in weeds that usually colonise tomatogrowing areas. More than 4800 plants belonging to 31 species and about 8000 thrips, including adults and larvae, were collected and analysed by Digoxigenin-labeled riboprobes. TSWV was the virus more frequently detected (percent of infection in parentheses) (3.5%), followed by PVY (1%), CMV (0,7%), AMV (0,7%) and INSV (0.2%). In tomato, INSV was found in mixed infection with TSWV. TSWV was also recorded in the adults of Frankliniella occidentalis (28%), Thrips tabaci (29%), and in other undetermined thrips species (31%) and larvae (14,5%). Diplotaxis erucoides, Fumaria officinalis, Oxalis acetosella, Sinapis spp, and Veronica spp were identified as new hosts for TSWV in Italy