AVERAGE DATES AND ACCUMULATED THERMAL REQUIREMENTS FOR DIFFERENT PHENOPHASES OF PEACH AS INFLUENCED BY CLIMATE
Knowledge of the influence of climatic conditions on the phenology of cultivated tree fruits allows growers and technicians to select the appropriate cultivars for a particular area and to schedule cultural techniques. Studies concerning heat requirements of different cultivars are valuable tools to avoid problems caused by lack of adaptation. This work attempted to improve flowering time modeling in peach by determining heat requirements for each phenophase between the calyx perceptible stage (C) and 12 mm fruit diameter under the climatic conditions of different growing areas in the Ebro Valley (Northeastern Spain). Data were collected on three peach cultivars (Big Top, OHenry and Andross), with ten orchards per cultivar. These cultivars are widely cultivated within the Ebro Valley and cover the full range of blooming times in this region. Phenological observations were performed twice a week on ten trees per orchard and hourly temperature data were obtained from meteorological stations near the orchards. The influence of site (characterized by its altitude) and year on phenophase occurrence date was evaluated for each cultivar. Average accumulated GDH requirements for each phenophase and type of cultivar were obtained. The dates for all phenological stages varied considerably among years and altitudes. The phenophase differences could be attributed to differences in temperature registered in the site. Heat accumulation did not differ between years or altitudes and was similar between mid- and late cultivars. Only the early-blooming Big Top had significantly lower requirements from the others for most of the phenophases. Models based on GDH accumulation for peach cultivars, clustered by bloom dates, could compensate for the lack of phenological records in the Ebro Valley area. Pheno-climatic analyses could be carried out with simulated flowering dates.
Santesteban, L.G., Miranda, C. and Royo, J.B. (2012). AVERAGE DATES AND ACCUMULATED THERMAL REQUIREMENTS FOR DIFFERENT PHENOPHASES OF PEACH AS INFLUENCED BY CLIMATE. Acta Hortic. 962, 277-284
Prunus pérsica (L.) Batsch, phenology, growing degree hours, modelling