Analysis of Progress and Spatial Pattern of Corky Bark in Grapes. Edna Tanne, Department of Virology, ARO, the Volcani Center, Bet Dagan, Israel . Ruth Marcus, E. Dubitzky, and B. Raccah. Plant Dis. 80:34-38. Accepted for publication 17 February 1995. Copyright 1996 The American Phytopathological Society. DOI: 10.1094/PD-80-0034.

The corky bark disease of grapevine is believed to be caused by a viral agent. The present study provides information on the distribution of the infection in a commercial vineyard of the seedless cultivar Thompson. An analysis of temporal progress of infection from April 1983 to April 1990 shows a gradual increase in the cumulative number of infected vines with a logistic rate parameter of 0.598 per year. The spatial pattern of infection was clustered in the first three monitoring dates. However, as the incidence of infection increased, the pattern became random. Biological explanations for the phenomena are discussed.