Flowering times of old and new apple varieties in South Tyrol

Abstract

A suitable pollen donor variety must not only have a pollen compatible with the main vari-ety, the flowering period of both varieties should also overlap sufficiently. The flowering time is crucial for the pollination of apples and thus influences yield and fruit quality. One particular question is whether new, promising varieties such as Minneiska (SweeTango®) or WA 38 (Cosmic Crisp®) have sufficient overlap of the flowering period with the current main South Tyrolean varieties such as Gala, Golden Delicious, or Cripps Pink (Pink Lady®) and can therefore be grown without an additional pollen donor. At the Laimburg Research Centre, the flowering dates of 236 different apple varieties were recorded with a standar-dized method. These were old local varieties, the current main, and new varieties. The surveys considered in this study were carried out between 2010 and 2020 at the locations Laimburg at 220 m a.s.l. and Latsch at 670 m a.s.l.. The result is a solid categorization of around 200 apple cultivars based on their relative flowering time. It is known that climatic conditions have a strong influence on the flowering duration. This fact was proven by the results over the years and at the different locations.