Metrics for studying berry growth kinetics in seedless grape cultivars (<i>Vitis vinifera</i> L.)

The process related to the changes in dimensions and mass of grape berry passes through two growth phases separated by a lag phase, can be described double sigmoid curve. onset their duration are important factors for understanding processes berries. A new method quantitative determination was developed present study. In this method, phase transition dates correspond times at which rate change curvature logistic (sigmoid) curve reaches an extreme value. tested on three seedless varieties, Sultanina, Ruby Seedless Rusalka 3, were tracked from anthesis harvest. For each model length, width harvest metrics - beginning, stabilisation end determined. It found that do not match shift relative other over time. comparison with phenological metrics, such as anthesis, veraison ripening, showed phenophases cannot used time scale record acceleration processes, they shifted metrics. An exception veraison, coincided beginning accelerated grapes during second following phase. presented current research is tool monitoring could help clarify links between visible berries ongoing within them. also analysis various follow law.