Abstract
The effect of aggregation of disease on estimating the amount of Botrytis cinerea in harvested winegrapes was simulated using computer models. As the degree of aggregation was increased, the estimated amount of disease increased. This error was reduced when more samples were obtained. When multiple samples (90) were taken from gondolas containing machine- or hand-harvested berries and the amount of B. cinerea-specific antigen quantified with an immunoassay, the machine-harvested berries had a more uniform distribution of antigen than did hand-harvested berries. To obtain the same confidence of estimation of the level of disease, one would take at least two samples per each gondola for hand-harvested berries and one per each gondola for machine-harvested berries.
- Received May 1992.
- Copyright 1993 by the American Society for Enology and Viticulture