Evaluation of re-infection by virus in virus free-garlic. Survey of vectors.

SOSA, M.C.; MUÑOZ, J.O.; NAVELINO, P.; GONZALEZ, H.

ACTA HORTICULTURAE

ISHS

Lugar: Mendoza; Año: 1997 vol. 2 p. 601 - 606

0567-7572

A detection system of viruses in garlic made the massive evaluation of materials obtained by meristem-tip culture easier. This allowed fields studies of re-infection and search of vectors. During 1992/1993 plots were planted in 3 locations. Trials with virus-free garlic minicloves were made and placed at distances varying from 0 to 25.000 m. of infected commercial crops. The healthy evaluation was made by visual appraisals of sympthoms, by host index for Carlavirus and by ELISA for Potyvirus. The search of vectors was made by gathering alive aphids and Moericke tramps. Control plots were made in anti-aphid tunnels. The results of re-infection gave a value of 100% in 1992 in plots next to commercial crops and 11% for plots 1000 m away. In 1993 plots next to commercial ones showed 22% and 34% in Villa Dolores and Totoral respectively. To 25.000m were 2% of infection and the plot under anti-aphid tunnels remmained virus-free. The positive values were for Potyvirus. Several specimens of Myzus persicae and Aphis sp. were detected on the cultures. Up to the moment virus symptoms were obtained on onions using M. persicae. The study of individuals caught in tramps shows that garlic crops are visited by several species of aphids such as M. persicae, Aphis spp., Macrosiphum euphorbiae, Schizaphis graminum and Brevicoryne brassicae.