래빗아이 블루베리 품종별 꽃눈의 내동성과 재배안전지역

Abstract

BACKGROUND: Rabbiteye blueberry(Vaccinium ashei)is one of the most widely grown blueberry types in theworld, together with Northern and Southern highbushblueberry(Vaccinium corymbosum). Rabbiteye blueberryhave higher soil adaptability and fruit productivity but lesscold tolerance to low temperature than highbush blueberry. The objective of this study is to investigate freezingtolerance of floral buds and establish a cultivation zone forrabbiteye blueberry cultivars. METHODS AND RESULTS: Bearing branches whichhave similar thickness and same number of floral buds werecollected in the early January at the blueberry germplasmpreservation plot located in Namhae Sub-station, NationalInstitute of Horticultural and Herbal Science in Gyeongsangnamdo. Cold response of bearing branches were investigated byelectrolyte leakage and freezing tolerance of floral budswere determined by ovary browning ratio of 50%(LT50). Cultivation zone was established based on mean annualextreme minimum temperature for 30 years, from1981to2010. The electrolyte leakage of bearing branches in rabbiteyeblueberry increased as temperature decreased and waslowest in ‘Brightwell’ but highest in ‘Bluegem’ when theywere kept in -5°C. Besides, the electrolyte leakageincreased in ‘Brightblue’, ‘Brightwell’, ‘Climax’, ‘Delite’,‘Gardenblue’, ‘Southland’ and ‘Woodard’ in -20°C. Freezing tolerance(LT50) was lowest in ‘Bluegem’ and‘Homebell’(-13.3°C), and highest in ‘Tifblue’(-25°C)among different rabbiteye blueberry cultivars. LT50 of‘Southland’ was from-15.0 to-16.7°C, that of ‘Delite’,‘Brightwell’,’ Austin’ and ‘Climax’ was -18.3°C, and thatof ‘Bluebelle’, ‘Woodard’ and ‘Powderblue’ was -20°C. CONCLUSION: This study indicate that The hardinesszones of rabbiteye blueberry were classified into Sixcultivation zones and cultivation zones of most cultivarswere the south of Jeollanam-do and Gyeongdangnam-do,except for ‘Tifblue.’