文心蘭花苞與花朵之乙烯生成不同,很小的花苞切下後立即密封,可以測得有乙烯產生,中等以上的花苞以至唇瓣剛開裂之半開張花朵均測不到乙烯生成,完全開張的花朵又會產生低量的乙烯。將花苞或花朵插於水中,定期測定乙烯,1日後均測不到乙烯之生成,等到花朵老化或花苞開張後開始老化時再有乙烯生成。乙烯在花朵外觀開始老化當日或次1日開始產生,到老化症狀很明顯時乙烯生成最高,之後乙烯生成漸減,呈現一個不很明顯的更年性曲線之變化。外加10ppm乙烯處理18小時會使枝條上的花朵壽命由15日減少為10日,花苞開張率及壽命也減少,因此花枝瓶插壽命跟著下降。用1ppm乙烯長時問處理,花朵會迅速老化,以10或50ppm處理,花朵老化速度並不會加快,說明乙烯作用飽和濃度應在1ppm或1ppm以下。這些結果顯示文心蘭是屬於對乙烯敏感的切花。去除花朵之花藥蓋會使花朵在數小時內產生乙烯,約l日後乙烯之生成下降到測不出來。這種去蓋的花朵通常會提早3日老化,乙烯生成也較早開始。將文心蘭側枝插水,去蓋使枝上的花朵早謝,卻會使剩下的小花苞閉張率增加並提高小花壽命。由於文心蘭花朵不論是否去除花藥蓋,老化時常於外觀上開始顯現老化黴狀之後才測得出乙烯生成,因此這些內生乙烯是否是引發老化的因素尚待探究。
Ethylene production could be detected from small bud and fully opened floret of Oncidium orchid when they were measured right after detachment. No ethylene was detected from big bud and half opened floret. When the bud and floret were held in water, ethylene production was not detectable in the first few days after detachment. During floret senenscene ethylene production increased on the day or one day after the floret showed symptom of senescence. It reached a peak and then declined. Exogenous 10ppm ethylene treatment for 18 hours shortened the life span of floret for 5 days. Bud opening and the life span of bud also decreased. Under 1ppm ethylene environment, Oncidium florets wilted quickly. Increasing ethylene concentration up to 10 or 50ppm, the floret wilted as fast as at 1ppm. These data indicated that Oncidiwn flower is sensitive to ethylene. Removal of pollinia cap would induce the floret to produe ethylene. The ethylene production rose in a few hours after de-capping. It gradually decreased and became undetected one day later. The de-capped floret wilted 3 days earlier than intact floret. Ethylene production of de-capped floret also rose earlier. De-capping resulted in early senescence of floret, but it increased bud opening and life span of buds on the same inflorescence. During floret senescence, ethylene production always rose later than the beginning of visiable senescence symptom. It is not clear whether the endogenous ethylene play an important role in inducing floret senescence.