Occurrence and distribution of sugar beet viruses in Lebanon

Abstract

Field surveys were carried out in the main sugar beet growing areas of Lebanon to assess the occurrence and distribution of viral diseases. A total of 1002 samples from 115 commercial fields were serologically assessed for Beet Necrotic Yellow Vein Furovirus (BNYVV), Beet Yellows Closterovirus (BYV), Beet Mosaic Potyvirus (BtMV), Beet Western Yellow Luteovirus (BWYV) and Cucumber Mosaic Cucumovirus (CMV). ELISA tests revealed that 39.5% of samples were infected with one or more viruses. BtMV was the most common (56.5%), followed by BYV (29.5%), BNYVV (17%) and BWYV (11%). Mixed infections were detected in 5.2% of the samples. CMV was not encountered. Direct tissue printing of plants infected with BtMV, BYV and BWYV on a nitrocellulose membrane gave very strong positive reactions.