篩選乙烯不敏感性及長花朵壽命之長壽花

Screening of Ethylene Insensitivity and Long Flower Longevity for Kalanchoe

乙烯在老化現象扮演關鍵角色，且會大幅地影響長壽花的花朵壽命。利用乙烯抑制劑處理長壽花，是目前減緩此觀賞壽命問題的主要策略。有些長壽花品種曾被測試其乙烯敏感性，以及被報導過乙烯抑制劑的處理效果。然而，仍需要大規模地對長壽花品種之乙烯敏感性進行調查，以育成乙烯不敏感之長壽花品種。本文中，採用了以離體單朵花為基礎的緊湊型篩選平臺，以快速地篩選達32 個栽培品種與4 個燈籠草屬物種。使用0.5、1 和10 μLL-1乙烯處理，觀察花朵老化現象並以花朵直徑量化其乙烯不敏感性。篩選出'Margrethe'、'Julianne'和'Heidi'為高度乙烯不敏感的3 個品種，以及12 個乙烯不敏感性略低之品種。由於花朵壽命也是盆花的重要性狀，且此性狀可能也與乙烯有關，因此也調查了受試品種的盆花單朵花壽命，並將單朵花壽命與乙烯不敏感性進行相關性分析。結果發現，單朵花壽命與乙烯不敏感性為正相關。依此結果，我們篩選出的乙烯不敏感品種中，有高比例為花朵長壽的品種。整體來說，本研究除了提供乙烯不敏感品種的篩選方法，也篩選出數個乙烯不敏感品種，這些品種也具有長花朵壽命之特性，有助於未來長壽花觀賞壽命之育種。

Ethylene plays a key role in senescence which would greatly affect flower longevity in Kalanchoe. Ethylene action inhibitors are the main solution today to alleviate the reduction of display life caused by ethylene for Kalanchoe. Ethylene sensitivity of some cultivars and ethylene inhibitor treatments have been reported previously. However, large scale surveys of cultivar sensitivity to ethylene are required to facilitate for breeding ethylene insensitive Kalanchoe. In this study, we adopted a rapid and compact system by using detached flowers to represent the ethylene sensitivity of each individual for 32 Kalanchoe cultivars and four Kalanchoe genus species. After exposure to 0.5, 1 and 10 μLL-1 ethylene for 1 or 2 d, three ethyleneinsensitive cultivars, 'Margrethe', 'Julianne' and 'Heidi', and 12 cultivars slightly sensitive to ethylene were identified by quantification of ethylene insensitivity which is assessed using percentage of flower diameter after ethylene treatments. Long flower longevity was shown to positively related to ethylene for potted Kalanchoe. Based on this correlation, most of ethylene-insensitive cultivars screened are those with long flower longevity. Taken together, this study not only provides a screening system for ethylene insensit ivity, but also isolates ethylene-insensitive cultivars with long flower longevity. The compact screening system and these ethylene-insensitive cultivars are effective tools and germplasms for breeding long display life Kalanchoe.