近年來蝴蝶蘭切花市場需求逐漸增加，但夏季高溫常造成開花品質下降與降溫成本過高，亟需選育耐熱品種，本研究擬建立對開花耐熱的蝴蝶蘭切花品種之檢定技術，並增加育種效率。測量8 品種大白花蝴蝶蘭分生苗葉片的細胞膜熱穩定性(Thermostability of Cell Membranes, CMT)，並與開花品質作回歸分析。結果顯示葉片之相對傷害值(RI) 與開花品質呈一直線負相關，RI 值低的品種於高溫下的開花表現較良好，用於實生苗族群檢定其RI 值與高溫開花品質的關係亦可得到相似的結果。此技術可用於篩檢耐熱之蝴蝶蘭切花品種。
接受日期：2015 年3 月16 日
Study on Heat Tolerance Index of Phalaenopsis
Yang, Yang and Wei-Chua Hu
Recently, market demand for Phalaenopsis cut flowers is increasing. High temperature in summer often cause poor flower quality and high cost for cooling. It is necessary to develop heat tolerance cultivars for flowering. The objective of this study was to develop techniques for identification of heat tolerant cultivars in Phalaenopsis and thus to improve breeding efficiency. Leaf thermostability of cell membranes (CMT) was measured and made regression analysis to flower quality under high temperature in 8 cultivars. Results showed there was a negative linear correlation in relative injury (RI) and flower quality only under high temperature condition. Cultivars with lower RI value had a better flower quality under high temperature. There was a similiar result in Phalaenopsis seedlings for the relationship between RI value and flower quality under high temperature. This technique can be used for selecting heat tolerant Phalaenopsis genotypes.
What is already known on this subject?
In many crops, thermostability of Cell Membranes(CMT) can efficiently differenciate heat tolerance in different cultivars, correlation between electrolyte leakage rate and flowering under high temperature have been reported in different floral cultivars.
What are the new findings?
There was rare report on using thermostability of Cell Membranes(CMT) to evaluate heat tolerance of orchid crops. This research analyzed the correlation of leaf cell relative injury(RI) in Phalaenopsis and flower quality under high temperature and successfully used physiological index for evaluating the quality of Phalaenopsis cut flowers. And this index have been used for heat tolerance seedlings selection.
What is the expected impact on this field?
This technique could be used in the selection of Phalaenopsis heat tolerant cultivars, reducing the cooling cost of summer cut flower production. On the other hand, choosing heat tolerance cultivars could increase Phalaenopsis cut flower quality in summer and make this industry more competitive.
Key words: Phalaenopsis, Cut Flower,
Thermostability of Cell Membranes
Accepted for publication: March 16, 2015