暗中斷與溫度處理對‘桃園三號’草苺 (Fragaria ×ananassa Duch.) 生育之影響

Abstract

台灣主要栽培草苺品種為‘桃園一號’和‘桃園三號’，兩品種產期為十一月至隔年四月。本試驗透過暗中斷與溫度處理，歸納‘桃園三號’在暗中斷與溫度處理後的生育與開花表現，以期能找到具經濟效益的產期調節方法，生產非當季的草苺。 暗中斷處理‘桃園三號’草苺7個月，再進行冷藏處理後，在夏季(七月)將植株置於戶外生長。結果顯示，帶介質冷藏植株生長勢較佳，葉面積較大、葉柄較長、走莖增加數較多，而無冷藏之對照組植株完全不增加走莖。除冷藏10℃-不照光組(10D)外，其餘處理皆達開花植株比例100%；其中，花序累加數最多者為無冷藏之對照組的1.6個花序，次之為10℃-照光組(10L)的1.3個花序。由以上結果顯示，冷藏處理對夏季開花影響較暗中斷處理小，結束暗中斷處理後，即使在夏季高溫環境中也能萌花芽。 進而探討暗中斷後，不同溫度對‘桃園三號’生育與花序分化之影響。溫度處理8週後，暗中斷植株皆不萌發花序，無暗中斷植株也僅有於15/10℃與30/25℃處理者增加0.4個花序。因此，將15/10℃處理與戶外溫度之植株置於較高溫30/25℃與25/20℃，觀察其開花反應。暗中斷處理植株經高溫處理11週後始抽出花芽，與在高溫處理中仍持續抽花芽的無暗中斷植株有顯著差異。 為了更清楚了解暗中斷後‘桃園三號’草苺植株在各種溫度中的開花表現，暗中斷後進行溫度處理4週，再以開花適溫處理。溫度處理4週後，暗中斷植株萌發約1.6個走莖，顯著多於無暗中斷組的0.2個走莖。溫度處理後，無暗中斷的對照組約增加1個花序，顯著多於暗中斷組的0個花序。暗中斷植株在開花適溫20/15℃下，再經7週以上，才能形成花芽。

Fragaria ×ananassa Duch. ‘Taoyuan No. 1’ and F. ×ananassa Duch. ‘Taoyuan No. 3’ are the main strawberry cultivars planted in Taiwan. The harvest season is from November to April. This study aims to figure out how night break and cold storage treatments affect growth and flowering on strawberry ‘Taoyuan No. 3’, and attempts to find the optimum way to regulate production season and produce out of season strawberries. After applying seven months of night break treatment and a period of cold storage, strawberry ‘Taoyuan No. 3’ plants were placed outdoor condition in July. The result showed that plants were planted in pot with cold storage treatment had better growth poteneial, larger leaf area, longer petiole length, and more increased runner numbers. Withou cold storage treatment, there were no runners increased. All the groups reached 100% of flowering plant proportion except the group placed at 10℃ without light (10D); Plants without cold storage treatment had the most accumulated inflorescences－1.6 inflorescences. The next was the plants placed at 10℃ with light (10L), which had 1.3 inflorescences. It showed that cold storage treatment had less influence on flowering. Strawberry ‘Taoyuan No. 3’ could blossom in summer in Taipei after night break treatment. To know how different temperature treatments influenced growth and flowering after night break, each group of plants was planced outdoor or at day/night temperatures of 30/25℃, 25/20℃, 20/15℃, and 15/10℃. Plants which were treated with night break didn’t sprout inflorescences eight weeks latter, even though plants without night break treatment only increased 0.4 inflorescences at 30/25℃ and 15/10℃. Therefore, 15/10℃ and outdoor groups were moved into higher temperature condition (30/25℃ and 25/20℃). Plants treated with night break started sprouting inflorescence after eleven weeks higher temperature treatment, while plants without night break treatment sprouted inflorescence immediately. After night break treatment, four temperature (15/13℃, 20/15℃, 25/20℃, and outdoor condition) were applied to strawberry ‘Taoyuan No. 3’ plants for four weeks, then they were moved into optimum flowering temperature (20/15℃). Plants treated with night break germinated about 1.6 runners but no inflorescence, significantly differed from plants without night break treatment, which had only 0.2 runners but germinated 1 inflorescence. Plants with night break treatment would finally sprout inflorescence after placing them at optimum flowering temperature 20/15℃for seven weeks.