Duration of the phenological stages of peach trees at tropics

Abstract

This study aims to evaluate the duration of the phenological stages and determine the adaptability and stability of reproductive and vegetative phases of peach trees under tropics with the purpose of optimizing the production system. The experiment was set up in a randomized plot design with 23 cultivars (‘Aurora-1′, ‘Biuti’, ‘Bonão’, ‘Centenário’, ‘Charme’, ‘Delicioso Precoce’, ‘Diamante’, ‘Douçura-2′, ‘Douradão’, ‘Dourado-2′, ‘Eldorado’, ‘Flordaprince’, ‘Jóia-3′, ‘Kampai’, ‘Libra’, ‘Maciel’, ‘Maravilha’, ‘Marli’, ‘Okinawa’, ‘Ouromel-4′, ‘Premier’, ‘Régis’, and ‘Tropical’) in 2014-2016. The average duration (in days) for the three years, between pruning day and each phenological stage (OS - sprouted buds had opened, onset of flowering – OF, full bloom – FB, end of flowering – EF, beginning of fruit harvest - BH, and end of harvest - EH) in each plot, was evaluated through visual observations including the chill hours accumulation(CA) of each cultivar for accumulated number of hours with temperatures (≤7.2 °C), (≤12 °C) and (≥25℃), the thermal demand, expressed in degree-days of development (GDD) and the adaptability and stability of OS and EH.