The basis of variation in size and composition of grape berries

The size and composition of grape berries is determined during the early stages of berry development by factors that govern cell division and cell expansion. Variation in berry size and composition is due to variability in these developmental processes. The aim of this study was to establish a methodology that would allow precise three-dimensional measurements of cell size in situ. The method uses confocal laser scanning microscopy and digital image reconstruction to visualise cells in whole mounts of cleared, stained berry tissues. Cells from the inner mesocarp of a single berry exhibited a much wider range of sizes and shapes than had previously been observed.