Postharvest Physiology and Handling Technology of Cut Eustoma Flowers

Abstract

1. 洋桔梗切花呼吸行為類似更年型果實之花卉，於25℃下更年高峰時，花朵的呼吸率和乙 烯釋放量分別為350 uLCO2 g-1 h-1 和 34.6 nL C2H4 g-1 h-1。 2. 小花初開時，花瓣細胞內部已開始出現老化之症狀，盛開時，細胞內部已失去隔室作用， 而此時表皮細胞外觀卻呈現最膨脹飽滿的狀態，當花瓣出現萎凋時，則細胞內部已受到 嚴重之破壞。 3. 於萎凋期之韌皮部及形成層細胞嚴重皺縮，而木質部導管細胞則維持正常之形態。小花 花梗於瓶插期間能維持較低之滲透潛勢，可保持較高吸水能力，以獲得相對較多量的水分。 4. 採後離水0-12 小時對瓶插壽命和垂頸率影響不顯著，依據鮮重和貯運時間，11.4 mgH2O/gFw/h 吸水速率，可供為推算立式可回收容器適當裝水量。 5. 內銷切花宜於成熟度較高（5 朵小花開放）時採收，若需長期貯運則宜於蕾期採收並配 合保鮮液處理。 6. 以1,000 ppm AVG 預措1 小時、100 mM 硼酸預措0.5 小時；900 ppb 1-MCP 預措8 小 時或 200 ppm AIB 加15﹪蔗糖預措4 小時，均能有效延長切花壽命。 In order to understand the postharvest physiology and the suitable technique of storage for cut Eustoma flowers, a series of experiment were conducted. The results are summarized as follows： 1. The patterns of changes in respiration rate and ethylene production during vase were characteristic of like-climacteric pattern. The rate of respiration and ethylene production of flower at 25℃ were 350 uLCO2 g-1 h-1 and 34.6 nLC2H4 g-1 h-1 at climacteric peak, respectively. 2. Senescence symptom of flower appeared at the slightly open stage, at the full open stage, the turgid epidermal cells of petal showed the decomposition of vacuole membrane, finally proceeded to serious destruction at the initiation of petal wilt. 3. The cells of phloem and cambium tissue wilted seriously but vessel cells remained unchanged at the wilting stage. The lower osmotic potential would keep the water uptake ability higher and persist water holding of pedicel tissue during the vase days. 4. No significant difference on the vase life and bent neck ratio of flower was found from the treatment of 0-12 hours after harvesting time before soaking. When the fresh weight of cut flower and the duration of transportation were concerned, the 11.4mg H2O gFw-1h-1 of water uptake rate could be used as a reference to estimate the amount of water needed of procona packing system. 5. Cut flower harvesting at high maturity （5 florets opened）is preferred for domestic market, but harvesting at tight bud stage might desirable for export. 6. Pretreatment of cut flower with 1000 ppm AVG for 1 hour, 100 mM boric acid for 0.5 hour,900 ppb 1-MCP for 8h or 200 ppm AIB＋15﹪sucrose for 4 hour were effective in prolonging the vase life