SEROLOGICAL DETECTION OF GRAPEVINE VIRUS A USING ANTISERUM TO A NONSTRUCTURAL PROTEIN, THE PUTATIVE MOVEMENT PROTEIN

Grapevine virus A (GVA) is implicated in the etiology of the rugose wo od disease. The coat protein (CP) and the putative movement protein (M P) genes of GVA were cloned and expressed in Escherichia coli and used to produce antisera. Both the CP and the MP were detected with their corresponding antisera in GVA-infected Nicotiana benthamiana. The MP w as first detected at an early stage of the infection, 6 to 12 h after inoculation, and the CP was detected 2 to 3 days after inoculation. Th e CP and MP were detected by immunoblot analysis in rugose wood-affect ed grapevines. The MP could be detected in GVA-infected grapevines tha t tested negative for CP, both with CP antiserum and with a commercial ly available enzyme-linked immunosorbent assay kit. The study shows th at detection of the nonstructural MP may be an effective means for ser ological detection of GVA infection in grapevines.