In a histological study carried out in Campinas, State of São Paulo, Brazil, it was shown that under field conditions, most of the buds differentiated between January and February (Majerovicz and Söndahl 2005). In that study, carried out from 1980 to 1982, the daily mean temperature in January and February varied from 21 to 25°C. In the same muni cipality, the daily mean air temperature between 1956 and 1982 was close to 23°C.