Aplicación de modelos logísticos doble sigmoide en el crecimiento de tres variedades de rosa de corte

The rose is a flower with widespread acceptance worldwide, and Colombia successfully produces rose stems for cutting due to its multiple favorable microclimates. However, meeting international market quality standards requires a rigorous cultivation program and growth models are a novel tool that allows for a more precise definition of phenological stages. The application of double sigmoid logistic models was evaluated in the growth of three varieties of cut roses ‘Freedom,’ ‘Pink Floyd,’ and ‘Mondial’ cultivated in soil under plastic cover conditions. A completely randomized design was implemented with three treatments corresponding to the three varieties. The Mondial, Pink Floyd, and Freedom varieties require 84.1, 82.6, and 77.4 days, to develop the floral button, thus requiring different amounts of thermal time to reach each phenological stage. Total chlorophyll content showed an upward trend until the end of the harvest cycle, reaching values of 64.7, 65.5, and 71.8 for the Mondial, Pink Floyd, and Freedom varieties, respectively. The earliest variety was Freedom, which needed only 1134 growth degree days (GDD), while the latest variety was Mondial, with 1233 CGDD. The Freedom variety had the highest floral button diameter and floral button length values. The increase in the diameter and length of the floral button followed a simple sigmoid pattern, while the stem diameter followed a double sigmoid pattern.