Occurrence of Cold Damage in Several Olive Cultivars in Coastal Area of Gyeongsangnam-do and at Different Low Temperatures

As farmers' interest in new subtropical crops with global warming is increasing, this study was conducted to evaluate the possibility of olive cultivation at open field in coastal area of Gyeongsangnam-do, Korea.At experiment sites in Geoje and Namhae, cold damage on shoots of 4-year-old olives, 'Frantoio', 'Verdale', 'Maurino', 'Lecino', 'Koroneiki', and 'Arbequina' was investigated after passing the lowest temperature, -10.9C in Geoje and -12.3C in Namhae in January, 2023.Cold damage was the least in Arbequina with 0% in Geoje and 17% in Nahae, while Koroneiki was the worst with almost 100% damage in both areas.Cold damage for 'Arbequina' trees of 2, 3, and 4 years old was tested at a cold chamber lowering temperature to -14C.As temperature decreased, the damage for the 2 years old gradually increased to 28% at -10C and 78% at -14C.However, even if temperature fell to -10C, the damage for the 3 and 4 years old was less than 9%, and below -11C, the damage for the 3 years old became higher than that of 4 years old, exhibiting 55% and 45% at -14C, respectively.After the low temperature treatments, electrolyte leakage of shoots increased with lowering temperature in younger trees and the absorbance by the TTC test clearly decreased in the 2 years old, compared to the 3 and 4 years old, indicating the cold damage was more severe in younger trees.It was concluded that the cultivation possibility of 'Arbequina' olive is high in areas where winter minimum temperatures are over -10C in coastal areas of Gyeongsangnam-do, and that the younger the tree, the more important it is to keep warm in winter.