(49(3):46-53)The Relationship between Cultivar’s Chilling Requirement and Planting Altitudes of Peaches

桃樹生產需累積足夠的低溫以打破樹體休眠，方能確保栽培成功，亦即桃基因遺傳的需冷量 (chilling requirement) 必需與產地的低溫累積量 (chilling accumulation) 相吻合。本試驗目的在於探討桃栽培種需冷量多寡與臺灣中部地區種植高度間的關係，據多年的經驗累積與二年的試驗調查結果顯示：低需冷桃樹（150 CU）在低海拔地區（農試所，海拔85公尺）種植，生長適應良好；另一方面高需冷桃樹（850小時）在高山環境下（武陵農場，海拔1950公尺）生育表現良好。由此可見海拔高度每提升2.7公尺，可累積1低溫單位，此一關係可用來評估台灣山區的低溫累積量。For successful production of peaches, the tree requires the accumulation of sufficient chilling temperatures to break dormancy. Thus the chilling requirement (CR) of the peach genotype needs to be matched with the chilling accumulated for the production area. The objective of this study was to determine the relationship between cultivar’s chilling requirement and planting altitude for the central area of Taiwan. Years of experience and 2 years of experimental work has shown that low-chill peaches (150 CU) are well adapted to low altitude growing conditions (TART, 85 masl) whereas high chill peaches (850 hours) perform well under high altitude (Wuling Veteran’s Farm, 1950 masl) conditions. Thus for every 2.7 meters in altitude, one chilling unit is accumulated. This relationship can be used to estimate the accumulated chilling in the mountainous areas of Taiwan