Temperature Changes Affected Spring Phenology and Fruit Quality of Apples Grown in High-Latitude Region of South Korea

Climate change has had a significant impact on apple phenology and fruit quality worldwide. Similarly, a decline in fruit quality has been observed in major apple-producing areas of Korea. It is predicted that the ideal cultivation areas for apples would need to shift toward higher latitudes due to these changes. Hence, the objective of this study was to assess the influence of climate change on apple cultivated in a higher-latitude region. To achieve this goal, we investigated the flowering and harvest times of apples. Additionally, we measured fruit weight, soluble solid content, and titratable acidity over a period of 20 years in a higher-latitude region in Korea. Subsequently, we examined the relationship between temperature, phenology, and fruit quality through the use of linear regression and correlation analysis methods. The 20-year meteorological data revealed a consistent rise in temperatures. Consistent with this trend, we found a significant advancement in budbreak and flowering dates for the two major apple cultivars grown in a higher latitude in Korea. Furthermore, the increase in temperatures has positively influenced fruit quality, indicating that climate change has an impact not only on phenology, but also on the quality of apples in Korea. Considering the projected gradual increase in temperature, our findings strongly support that higher-latitude regions in Korea have the potential to become optimal locations for apple cultivation.