蝴蝶蘭花朵寒害後不同部位之老化、乙烯生成及電解質滲漏

Senescence, Ethylene Production and Electrolyte Leakage of Different Parts of Chilled Phalaenopsis Flower

黃肇家(Chao-Chia Huang) ； 潘美慧(Mei-Hwei Pan) ； 王自存(Tsu-Tsuen Wang)

《中華農業研究》 46卷2期 (1997/06) Pp. 167-180

https://doi.org/10.29951/JARC.199706.0006

摘要

本試驗探討蝴蝶蘭花朶發生寒害時，花朶之不同部位之老化、乙烯生成及電解質滲漏之變化。蝴蝶蘭花朶在7℃貯放10日會引發寒害，花朶加速老化，花朶各部位之老化順序不同，以蕊柱最早，其次為子房與小花梗，而唇瓣、花瓣及花萼最慢。以切離並密封方式測定各個花朶部位之乙烯生成，所得之結果顯示蕊柱之乙烯生成最早開始上升，而且速率最高可達40nl/g/hr，子房、小花梗及唇瓣居中，花瓣及花萼之乙烯生長量則非常低。以直接密封方式測定完整花朶上不同部位之乙烯生成，所得之結果以小花梗之乙烯生成速率最高，蕊柱之乙烯生成速率僅1.88nl/g/hr。然而當小花梗被切離後，其乙烯生成速率立即下降為未切離時之1/3。以流通方式連續測定完整花朶上不同部位之乙烯生成，結果以包括花瓣及花萼在內之花被生成量最多，速率在第四日達到最高；蕊柱之生成速率不高，僅在第1.5日出現高峰。受寒害花朶在移至20℃後各部位之ACC氧化酶活性均明顯提高，蕊柱、子房及小花梗在第二日即開始增加，前二者且持續增加至第五日達到最高約350nlC2H4/g/hr。唇瓣、花瓣及花萼至第四日後開始增加至第六日達到一較低之高峰。ACC氧化酶活性之變化與各部位以切離方式測得之乙烯生成速率之變化相當吻合。花朶各部位之電解質滲漏於冷藏期間即開始增加，其中以蕊柱和小花梗之上升最多；移入20℃後蕊柱及其他部位之電解質滲漏均會下降，經二日後再度上升，唯有小花梗之電解質滲漏於移溫後不再下降，且一直升高。上述之結果顯示蝴蝶蘭花朶受到寒害時各部位之反應程度並不一致，蕊柱反應最早且最明顯，子房、小花梗與唇瓣居中，花瓣與花萼最慢。此結果亦顯示寒害蝴蝶蘭花朶之老化及乙烯生成可能是花朶各部位分工配合的結果，因為蕊柱老化最早，其乙烯生成最早上升，速率亦最高，而且部位間有乙烯流通之現象，因此蝴蝶蘭花朶受寒害老化時，可能先由蕊柱產生乙烯先老化，再誘發其他部位如花瓣與花萼等產生乙烯並導致花朶最後之老化；此一現象與蝴蝶蘭花朶授粉引起之乙烯生成與花朶老化頗為類似。

關鍵字

蝴蝶蘭花朶 ； 寒害 ； 乙烯生成 ； ACC氧化酶 ； 電解質滲漏

並列摘要

This study investigates the senescence, ethylene production and eletrolyte leakage of different parts of chilled Phataenopsis flower, The vase life of Phalaenopsis flower was reduced to halve after being stored at 7℃ for 10 days. Symptoms of senescence first appeared on the column, followed by ovary and pedicel; while petal, sepal and labellum were the lowest. Ethylene production from each flower parts were measured from either excised flower parts or intact flower. A visible and rapid increase in ethylene production was observed in excised column. Its ethylene production rate peaked on the 5th day with value near 40nl/g/hr. Ovary, pedicel and labellum were about one tenth of that of the column, and excised sepal and petal produced almost no ethylene. When ethylene production rate was measured by sealing intact flower parts directly, the highest ethylene produciton rate was observed with the pedicel, and the column produced very small amount of ethylene at 1.88nl/g/hr. However, the ethylene production rate was reduced to one third when the pedicel was excised right after the above measurement. Ethylene production from intact flower parts were also monitored by using a flow-through system. Flower parts including petal, sepal, ovary and labellum all together were the major site of ethylene production, which began to increase on the 2nd day and reached a peak on the 4th day, coincide with the fading of perianth. Marked increases in ACC oxidase activity were observed in all flower parts after chilling treatment. In column, ovary and pedicel, ACC oxidase activity started to increase on the 2nd day and the former two continued until the 5th day, reaching a peak value of 350nlC2H4/g/hr. In labellum, petal and sepal, ACC oxidase started to increase after 3 days and reached a smaller peak on the 6th day. Changes in ACC oxidase activity marthes well with the changes in ethylene production in excised flower parts. Increase in electrolyte leakage were observed in all flower parts during cold storage with the column and pedicel increased most. Except the pedicel, all other flower parts showed decrease in eletrolyte leakage upon removal from cold but increased again after 2 days. Our results indicated that each flower part responded differently toward chilling treatment. The column seemed to be the most sensitive part in response to chilling stress, while the ovary, the pedicel and the labellum followed, with the petal and the sepal being the slowest to respond. Our result also suggested that the chilling induced ethylene production and senescence in Phalaenopsis flower might be the result of cooperation of different flower parts, similar to that of pollination. Ethylene biosynthesis was rapidly induced in the column after chillig treatment. The ethylene or ACC formed in the column may induce ethylene production in other flower parts such as petal and sepal, and resulted in the eventual senescence of the flower.

並列關鍵字

Phalaenopsis flower ； Chilling injury ； Ethylene production ； ACC oxidase ； Electrolyte leakage