Phenological and physicochemical changes during fruit development in two peach cultivars in the high tropics

Résumé 0

Several aspects of the development of the peach fruit under tropical conditions are unknown, this information allows agronomic practices to be carried out with technical criteria. Therefore, the objective was to determine the different changes and phenological changes of peach fruit depending on the Growing Degree Days (GDD) in the varieties 'Dorado' and 'Rubidoux', grown in the Colombian high tropics. This study randomly selected 51 trees and 100 flowers per plant that were in full flowering for sampling every 15 days until harvest to determine physical variables such as firmness, color index of the epidermis and pulp, and chemical properties such as soluble solids, titratable acidity, and respiratory rate. From full bloom to harvest, the Dorado and Rubidoux varieties took 1081.8 GDD (153 days) and 1667.1 GDD (205 days) respectively. The firmness increased in the two cultivars during phase 1 of development, then decreased until harvest. The color index of the epidermis and pulp increased during ripening, indicating yellow tones in the two varieties. The soluble solids increased continuously, with final values of 15.9 ± 0.9 and 15.5 ± 0.3 °Brix. The acidity increased during phase 2 and then decreased during ripening. The respiratory rate decreased between phase 1 and 3, with an increase in phase 2, which is related to the lignification of the endocarp in the two cultivars. These results contribute to the understanding of the development of the two peach cultivars under tropical conditions.