台灣重要經濟酪梨栽培品種之開花習性

Observations on Flowering Phenology of Main Avocado (Persea americana Mill.) Cultivars in Taiwan

調查‘嘉選一號’、‘嘉選二號’、‘嘉選三號’、‘嘉選四號’、‘Halemana’、‘Hall’、‘Choquette’、‘紅心細葉’、‘79-6-5-3’共9個台灣主要酪梨栽培品種之花序發育狀態與開花習性。綜合三年之資料顯示，9品種之開花日期約在十二至四月間，可分為早花、中花與晚花等三類型。早花品種為‘嘉選四號’與‘嘉選三號’，於十二月初開花至四月初。中花品種為‘79-6-5-3’、‘嘉選一號’、‘Halemana’，花期由一月底到四月初。晚花品種為‘Hall’、‘嘉選二號’、‘紅心細葉’，花期從二月底到四月中。各品種盛花期約持續1-2個月，開花期間溫度較高會使得盛花期的時間佔總花期的比例降低，且有花期提前結束之現象；晚花品種可能由於花芽形成過程間溫度較高，使得花芽發育較慢，造成花期結束較晚之情形發生。在正常氣候條件下，‘嘉選一號’、‘嘉選二號’和‘Hall’下午開雌花為B型品種外，其餘早上開雌花皆為A型品種。 The flower bud development and flowering behavior of 9 main avocado cultivars (‘CAES 1’, ‘CAES 2’, ‘CAES 3’, ‘CAES 4’, ‘Halemana’, ‘Hall’, ‘Choquette’, ‘Hung Shin Shi Yeh’, ‘79-6-5-3’) in Taiwan were observed for a period of three years. Data showed that total 9 cultivars flowered form December to April and could be divided into early, middle, and late blooming groups. ‘CAES4’ and ‘CAES 3’ are early blooming cultivars and flower from early December to early April. Middle blooming cultivars includes ‘79-6-5-3’, ‘CAES 1’ and ‘Halemana’, which flower from late January to early April. ‘CAES 2’, ‘Hung Shin Shi Yeh’ and ‘Choquette’ avocado are late blooming cultivars and flower from late February to mid April. The full-bloom period of 9 cultivars is about 1 to 2 month. Warmer temperature during flowering period may lower the percentage of full-bloomed period and precede the end of flowering period. However, for late blooming cultivars, warmer temperature during flower bud formation may decrease development rate and delay the end of flowering period. In normal conditions, except for ‘CAES 1’, ‘CAES2’, ‘Hall’ avocado which are defined as B type cultivars, others are A type cultivars.