Shoot-Based Sampling of Vitis vinifera Clusters

Abstract

The weights of individual Cabernet Sauvignon, Merlot, and Chardonnay clusters were found to be significantly correlated with the numbers of clusters on the shoots from which each cluster grew. Based on this and other findings, a new sampling strategy was devised that used procedures that encompassed block-shape geometry and distributional characteristics of clusters grown on sampled shoots. The vine was chosen randomly, the vine shoot to be sampled was chosen systematically, and then each selected cluster was chosen randomly. This recommended composite random-with-systematic-sampling approach was motivated by the need to minimize biases attributable to subjective judgments made in the field, such as overselection of uncharacteristically large clusters.