기후변화에 따른 강원 지역 사과 품종별 생육 변화 및 개화기 저온 스트레스 내성 구명
Assessment of Growth Responses and Tolerance to Low-Temperature Stress during Apple Flowering under Climate Change in Gangwon Region
- 주제(키워드) 도움말 apple , climate change , tolerance , low-temperature stress
- 발행기관 국립강릉원주대학교 일반대학원
- 지도교수 도움말 허재윤
- 발행년도 2025
- 학위수여년월 2025. 8
- 학위명 박사
- 학과 및 전공 도움말 일반대학원 원예학과
- 세부분야 해당없음
- 실제URI http://www.dcollection.net/handler/kangnung/000000012143
- UCI I804:42001-000000012143
- 본문언어 한국어
초록/요약 도움말
1. 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 solids 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. 2. Characterization of Frost Injury Tolerance during the Flowering Period and Associated Gene Expression Profiles in Different Apple Cultivars Climate change poses major challenges to global agriculture, including an increased risk of frost events that threaten apple production in temperate regions. This study aimed to evaluate genetic differences in frost tolerance among flowers of seven apple cultivars grown in Korea, with the goal of developing frost-resistant cultivars to mitigate climate change impacts. Flower samples were collected at full bloom, and frost tolerance was tested under simulated conditions using a refrigerated thermo-hygrostat set to -2°C. Frost damage was assessed using two metrics: Total Flower Frost Damage Rate (TFFD) and King Flower Frost Damage Rate (KFFD). Over the three-year study, 'Arisoo' demonstrated consistently strong frost tolerance based on TFFD and KFFD results, emphasizing its suitability for breeding programs. In contrast, 'Fuji' emerged as the frost-sensitive cultivar. These two cultivars were selected for transcriptome analysis to explore the molecular mechanisms underlying frost tolerance. Transcriptome analysis identified 44,677 unigenes, with significant differences in gene expression between 'Arisoo' and 'Fuji' under frost stress. Functional annotation using GO and KEGG pathway analyses revealed key pathways and genes associated with frost tolerance, including those involved in plant hormone signaling and the MAPK pathway. Seven candidate genes were validated using qRT-PCR, confirming their higher expression levels in frost-tolerant cultivar compared to frost-sensitive ones. This research provides valuable insights into the genetic and molecular mechanisms of frost tolerance in apple flowers. These findings contribute to the development of resilient apple varieties and sustainable production systems that address the challenges posed by climate change. 3. Effect of Rootstock Type on Chilling Injury Tolerance during the Flowering Stage in Apple This study aimed to evaluate the impact of rootstock type on low-temperature stress tolerance during the flowering period of ‘Fuji’ apples by examining pollen germination characteristics according to different rootstocks. Pollen germination was tested under nine temperature conditions ranging from 5°C to 45°C. When temperatures were either lower or higher than the optimal germination temperature, pollen germination rates declined significantly, and differences in germination rates were also observed depending on the rootstock. Based on the maximum and minimum germination temperatures, the widest temperature range for pollen germination was observed in the M.26 rootstock (43.79°C), while the narrowest range was found in B.9 (40.16°C). A similar trend was seen in the measurement of pollen tube length under the same conditions: M.26 exhibited the widest temperature range for pollen tube elongation (37.52°C), while B.9 had the narrowest (36.53°C). Furthermore, the effect of low-temperature stress during flowering on proline content was examined. Under low-temperature stress (10°C), M.26?which had shown superior pollen germination?also exhibited the highest proline content, with an increase of 1.89 times compared to the non-stress condition (25°C). Similarly, antioxidant activity, including CAT, POD, and SOD enzyme activities, was highest in M.26, and the rate of increase compared to the non-stress condition was also the greatest. These results suggest that pollen germination characteristics under low temperatures can vary depending on the rootstock, and such differences may influence overall productivity. However, since rootstock selection also affects fruit quality, a comprehensive evaluation considering both cold stress tolerance and fruit traits is necessary, warranting further research. 4. Influence of Rootstock Type on Fruit Quality Traits of the 'Fuji' Apple Cultivar This study investigated the effects of three dwarfing rootstocks (M.9, M.26, and B.9) on the fruit quality and antioxidant properties of ‘Fuji’ apples over a three-year period. Fruit weight varied significantly depending on both the rootstock and the growing year. M.9 produced the largest fruit in 2022 and 2023, whereas M.26 yielded the heaviest fruit in 2024. In contrast, B.9 consistently produced the smallest fruit across all years. Among the rootstocks, M.26 exhibited the highest yield per tree, demonstrating superior potential in terms of productivity. However, given that planting density can be influenced by rootstock vigor, further evaluation of yield per unit area by rootstock is necessary. Soluble solids content (SSC) was highest in B.9, whereas titratable acidity did not differ significantly among rootstocks, suggesting that acid metabolism may be more influenced by environmental factors than by rootstock selection. Fruit firmness was consistently highest in B.9, while M.9 and M.26 produced relatively softer fruit. Color parameters varied depending on the year and rootstock, but no significant differences were observed when averaged over the three-year period. Antioxidant properties showed rootstock-dependent variations in individual years, but no significant differences were found in the three-year average. These findings indicate that rootstock selection significantly influences key fruit characteristics, including fruit weight, SSC, firmness, and productivity. Further research is warranted to assess rootstock performance under diverse environmental conditions, providing scientific guidance for optimizing apple production strategies in high-latitude regions.
more목차 도움말
Ⅰ. 서 론 1
1.1. 연구배경 및 필요성 1
1.2. 연구목적 및 기대효과 4
Ⅱ. 연구사 5
2.1. 기후변화와 사과 재배적지의 변화 5
2.2. 저온피해 발생 메커니즘과 내동성 8
2.3. 사과의 휴면 기작과 저온 스트레스 내성 12
2.4. 사과 대목의 주요 특성과 저온 스트레스 내성 16
Ⅲ. 연구내용 19
Chapter 1. 기후변화에 따른 강원 지역 사과의 생물계절 및 과실 품질 변화 분석 19
3.1.1. 서언 19
3.1.2. 재료 및 방법 21
3.1.3. 결과 및 고찰 24
3.1.4. 적요 36
Chapter 2. 사과 품종별 개화기 서리피해(frost injury) 내성 차이와 유전자 발현 특성 구명 37
3.2.1. 서언 37
3.2.2. 재료 및 방법 39
3.2.3. 결과 및 고찰 45
3.2.4. 적요 76
Chapter 3. ‘후지’ 품종의 대목별 개화기 화분 발아 특성 및 저온장해(chilling injury) 반응 차이 구명 78
3.3.1. 서언 78
3.3.2. 재료 및 방법 80
3.3.3. 결과 및 고찰 84
3.3.4. 적요 97
Chapter 4. 대목의 종류가 ‘후지’ 품종의 과실 품질에 미치는 영향 98
3.4.1. 서언 98
3.4.2. 재료 및 방법 100
3.4.3. 결과 및 고찰 104
3.4.4. 적요 120
Ⅳ. 종합고찰 121
Ⅴ. 인용문헌 125
Abstract 152
