The influence of temperature on Australian pome fruit flowering.

Flowering development of pome fruit trees is dependent on local environmental conditions. The main driver in the timing of pome fruit flowering is temperature. However, understanding of the effect of temperature at an individual bud scale, is limited. The main purpose of this research was to investigate the differences in green tip timing, one of the earliest stages of flowering development, between bud types and potential temperature drivers. Changes in climate conditions may influence flowering timing potentially leading to a rise in the variability of fruit maturation, increasing harvesting costs as more picks are required. In addition, greater variability can potentially affect cross-pollination as varieties that pollinate each other may have different flowering at different times, limiting pollination potential. Furthermore, a better understanding of the relationships between temperature and individual bud behaviour will assist in assessments of future impacts of climate change on timing of flowering. Data from three different types of buds from ‘Cripps Pink’ apple were collected for 2012 and 2013. The study sites, which represent different climatic conditions, were Applethorpe (QLD), Shepparton (VIC) and Manjimup (WA). Statistical tests were applied to the datasets to evaluate possible differences in green tip emergence between bud types, sites and years.