Winter damage to apple trees in South Tyrol

Winter damage to Southern Tyrolean apple trees

Introduction
Winter damage to apple trees in South TyrolWinter damage to apple trees in South Tyrol occurs mostly in the Vinschgau valley and causes considerable financial losses (6 Mio € per year) due to retarded shooting or die back of trees. The causes of this type of winter damage are not fully understood. Frost damage could be one possible explanation. Therefore frost resistance of root and stem tissues and their freezing behaviour is analysed in different apple varieties comparing several sites. Our results should provide (a) a basis for avoiding winter damage and (b) assist growers in future selection of varieties and growing sites.

Research Questions

  • Artificial induction of symptoms of winter damage
  • Seasonal changes in frost resistance in roots and woody stem tissues of different apple varieties from different growing sites
  • Correlation of frost resistance (hardening and dehardening) with temperature and photoperiod
  • Determination of osmotic water potentials in different stem tissues in correlation to frost resistance
  • Freezing patterns in different organs as analysed with differential infrared video-thermography

Funding
Forschungsförderungsmittel der Südtiroler Landesregierung - Projekt (PJ 81817) "Winterschäden an Südtiroler Apfelbäumen" (PI: Gilbert NEUNER)
PhD grant from the Verein zur Förderung der wissenschaftlichen Ausbildung und Tätigkeit von Südtirolern an der Landesuniversität Innsbruck granted to Manuel Pramsohler 

Personnel involved
Manuel PRAMSOHLER
Gilbert NEUNER

Cooperations
Südtiroler Beratungsring für Obst- und Weinbau, Lana, Italy