糖類與植物生長調節物質對金花石蒜貯運後開花品質之影響

Abstract

金花石蒜 (Lycoris aurea Herb.)為台灣原生球根花卉之一。切花供應外銷需經長時間於低溫下貯運，但經低溫貯運後小花常會出現轉色不全、無法開放等小花畸形之問題而影響外銷品質。因此，為了改善金花石蒜切花貯運後之品質，本試驗包括了：1. 測量切花於不同溫度下之呼吸速率與乙烯生成率之變化。 2. 使用不同濃度之葡萄糖及蔗糖進行預措處理及不同種類之植物生長調節劑作噴灑處理，觀察其對貯後各項開放品質之影響。 3. 分析切花瓶插時花莖及正常小花內之醣含量變化，並比較畸形小花與正常小花醣含量之差異。 金花石蒜切花於不同溫度下 (0℃、5℃、10℃、20℃、25℃) 之呼吸率隨溫度的增加而增加，低溫貯藏可降低切花之呼吸率。而切花在不同溫度下乙烯生成皆極少。切花經不同溫度貯藏後於25℃中觀察其瓶插之表現，經0℃貯藏之切花呼吸率皆隨花朵開放而漸漸升高，至盛開期達高峰；但經5℃貯藏之切花其呼吸率則呈現一平穩的狀態。經低溫貯藏後之切花其乙烯生成量雖然也非常微少，但在瓶插第6天時似乎有微小的高峰，可能與切花之老化有關。 以1.5%之葡萄糖與1%、1.5%及 2%之蔗糖預措可有效降低小花畸形率，較對照組少8 ~14 %；醣類預措也可增加切花之吸水量，且蔗糖較葡萄糖之效果為好，但對瓶插壽命則無影響。未經貯藏之切花其花莖內之葡萄糖及果糖含量會隨著瓶插天數的下降，蔗糖含量則會逐漸上升。當切花經5℃貯藏10天，與未貯藏切花不同的是蔗糖含量沒有出現上升的趨勢，可能是低溫貯藏影響了花莖內葡萄糖與果糖轉換成蔗糖之能力。未開放小花內之醣含量變化方面，以成熟度較高的小花含有較多的葡萄糖與果糖，其中以葡萄糖為主要成份。畸形花與正常花內部之葡萄糖與蔗糖含量呈現明顯差異；與正常小花相比較，畸形花內部之葡萄糖含量偏低、蔗糖含量偏高；瓶插第5天時，畸形3級小花其葡萄糖含量約為正常3級小花之0.6倍，蔗糖含量則約為正常3級小花之2倍。因此畸形花的產生與其內部之醣含量似乎有相關性。 切花經20、50、100、200ppm之BA或GA混合100 ppm之DCIA噴灑處理後，小花開放率皆顯著增加，尤以200ppm之BA處理及200ppm之GA處理可使小花開放率提高至92 %以上，且200ppm之GA處理可使小花畸形率明顯下降。100ppm之BA處理及200ppm之GA處理可使小花之鮮重增加，200ppm之GA處理可有效提高小花開放整齊度；另外，20、50、100、200 ppm之BA或GA噴灑處理皆可使小花花苞之生長率提高，但對於切花之瓶插壽命上則無明顯影響。然而，單獨使用75、100、125 ppm之BA或GA，藥劑中不添加DCIA作噴灑處理，對小花之畸形率、開放率及瓶插壽命則皆無明顯影響。ABA噴灑處理對小花之畸形率、開放率無影響，但使切花之鮮重明顯降低。100ppm之‘益收’噴灑處理使小花花苞生長率及開放率明顯降低，也使切花莖部腐爛率提高，至瓶插壽命結束有70%之切花莖部腐爛。

Abstract Golden spider lily (Lycoris aurea Herb.) is a flowering bulb native to Taiwan. The storage under low tempwrature usually cause the floret can’t turn yellow or unopen, and this is become a limit factor during export. In order to improve the quality of golden spider lily cut flower after storage, we did some experiment include: 1. Variation of respiration and ethylene under different temperature. 2. Pulsing with glucose and sucrose or spray with different plant growth regulators. 3. Analyzing the sugar content of the stem and different stage of floret during vase period. The respiration is rising with temperature increasing. When cut flowers were stored at low temperature, which could reduce the respiration. No matter cut flowers were stored at any temperature, the production of ethylene is always very low. Respiration is rising with flower opening when cut flowers were stored at 0℃ for 10 days, but stored at 5℃ were not. Although the production of ethylene is also extremely low when cut flowers were stored at low temperature for 10 days, there was a higher peak at 6 days in vase, it may had relation with senescence of cut flowers. 1.5% gucose and 1%, 1.5%, and 2% sucrose pulsing can reduce the percentage of abnormal floret to 8-14 %. Sugar pulsing can increase the water uptake of stem and sucrose is more efficient than glucose. There is no significant different on vase life of cut flowers. Glucose and fructose content of stem is decreasing with vase period, and sucrose content is increasing. But when cut flowers were stored at 5℃ for 10 days, sucrose content is increasing during vase period. The result may because the activity of glucose and fructose inverse to sucrose is affected by low temperature. There are more glucose and fructose content in buds which is more mature, especially glucose. The abnormal florets have higher content of sucrose and lower content of glucose compared with normal florets. Glucose content of abnormal floret at ‘stage 3’ was 6-fold compared with normal floret, and sucrose content was 3-fold. Thus it has some correlation between abnomal floret and sugar content itself. Cut flower treatment with 20, 50, 100, 200ppm BA or GA mixed 100 ppm DCIA spray treatment can increase the flower opening up to 92%, especially with 200 mg l-1 BA and 200mg l-1 GA spray. 200 mg l-1 GA spray also can reduce the percentage of abnormal flowers to 36.36%. 100 mg l-1 BA spray and 200 mg l-1 GA spray can increase the fresh weight of flower, and 200 mg l-1 GA spray can increasing the percentage of fully opening flowers in vase. BA and GA treatment also can enlarge the size of flower, but it is no significant efficient on vase life. However, 75, 100, 125ppm BA or GA spray treatment without DCIA is no benefit to flower opening, abnormal and vase life. ABA spray can reduce the fresh weight of flower, but it is no deleterious on the percentage of flower opening and abnormal. 100 ppm Ethephon spray can reduce the flower opening and increase the percentage of stem which decayed, there is about 70% after Ethephon treatment.