Time-to-event analysis to evaluate dormancy status of single-bud cuttings
Shoots of Chardonnay (CH) and Cabernet Sauvignon (CS) were sampled weekly starting in August and ending around the first week of December from 2013 to 2016. Nodes from the third to the fifth basal position were clipped in single-node cuttings. Eighteen cuttings were used per sample during the first three years and 30 cuttings were used for the final year. Cuttings were placed on aluminum trays filled with moist sand substrate. The trays were placed in a growth chamber under forcing conditions at a temperature of 24±2°C with 15 hours of light. Cuttings were observed every two days and the number of days between sampling and the appearance of a green leaf tip in the buds, classified as budbreak was recorded and named duration to budbreak. For the samples that were collected from 2013 to 2015, the recording of duration to budbreak was carried out until the last week of March of the subsequent year. For samples from 2016, the evaluation finished at the end of February of 2017. Data were analyzed based on the time-to-event characteristics of the variable in order to estimate the endodormancy onset and release. Data includes the year of the sample, the sampling date, the sampling day of year (Julian calendar), cultivar, # of cutting of each sample, budbreak day in day of year (Julian calendar), duration to budbreak (budbreak day minus sampling day) and censored data.