乙烯及1-Methylcyclopropene對蝴蝶蘭花朵壽命之影響

Abstract

本研究以台灣蝴蝶蘭(Phalaenopsis amabilis)為植物材料，研究乙烯及1-methylcyclopropene (1-MCP)對花朵壽命的影響，探討蝴蝶蘭花序上不同發育階段之花朵對於乙烯敏感度的差異、乙烯作用抑制劑1-MCP對於蝴蝶蘭的絕對保護效期（本研究定義絕對保護為完全不受2 μL．L-1乙烯之影響）及欲達到絕對保護成效所需的處理條件，以提供Phal. amabilis前處理1-MCP的精確資料。 台灣蝴蝶蘭遭遇2 μL．L-1乙烯逆境會造成花朵及花苞快速萎凋，以較低濃度(0.3 μL．L-1)處理，觀察到花序上不論是已綻放的花朵或發育中的花苞，皆隨發育階段的成熟對於乙烯的敏感度提高，且花朵又較花苞敏感。同一花序中，成熟的花朵遭遇0.3 μL．L-1乙烯逆境後，於第26小時有乙烯大量產生的高峰；但最幼嫩的花朵，在處理乙烯後，乙烯產生量與對照組無異。 台灣蝴蝶蘭前處理1-MCP可以抑制外施乙烯造成的花朵萎凋，前處理濃度或時間會影響1-MCP對蝴蝶蘭的保護成效，而1-MCP的最低有效濃度似隨植株生理狀況及處理之季節變化而異。本研究結果顯示蝴蝶蘭盆花前處理1-MCP 12小時，縱使濃度低至0.005 μL．L-1，仍可降低花朵萎凋率，亦即只要有1-MCP的保護皆可減緩乙烯所造成的花朵快速萎凋，然欲達絕對保護成效，所需最低濃度為0.1 μL．L-1；前處理時間並可大幅縮短，1-MCP前處理濃度為0.05 μL．L-1時，處理時間應長於1小時，而處理濃度提高為0.2 μL．L-1時，只要處理0.5小時亦可達到絕對保護成效。此外即使將蝴蝶蘭花朵遭遇的乙烯逆境提高至20 μL．L-1，前處理蝴蝶蘭0.1 μL．L-1 1-MCP 12小時的保護成效不受影響。 蝴蝶蘭以0.8 μL．L-1 1-MCP前處理8小時，再分別於處理後不同天數給予乙烯逆境，比較花朵萎凋情形，結果顯示1-MCP對Phal. amabilis花朵的絕對保護效期約為6-8天；為瞭解多次施用1-MCP對於保護效期的影響，分別對蝴蝶蘭前處理一、二或三次之1-MCP，而後於不同天數給予2 μL．L-1乙烯逆境，由試驗結果得知，多次施用1-MCP可以延長保護效期，且三次施用可使1-MCP對台灣蝴蝶蘭的保護效期最少延長到24天。

In order to obtain information on anti-ethylene protection of 1-Methyl -cyclopropene (1-MCP; an ethylene action inhibitor ) in Phalaenopsis amabilsi, sensitivity to ethylene of flowers and buds in different developing stages, the residual effect of 1-MCP, and the interaction of 1-MCP concentration and fumigation time were determined. Flower wilting of Phal. amabilis was induced by 2 μL．L-1 ethylene. Sensitivity to ethylene increased as the maturity of flowers or buds increased. However, flowers were more sensitive to ethylene than buds. Ethylene production was increased when full-opened flower were exposed to 0.3 μL．L-1 ethylene, and peaked 26 hours after treatment. However, ethylene production was similar in ethylene-treated and untreated young buds. Pretreating Phalaenopsis amabilis with 1-MCP inhibited ethylene-induced senescence. However, effectiveness of 1-MCP depends on treatment duration and concentration. The data show pretreated Phal. amabilis with 1-MCP for 12 hours decresed flower wilting even at a very low concentration of 0.005 μL．L-1. Nevertheless, for a complete blocking of ethylene action (no damages by 2 μL．L-1 ethylene), a concentration of 0.1 μL．L-1 was required. The fumigation duration can be reduced to 1 hour. Moreover, the treatment duration should be longer than 1 hour when 1-MCP concentration was 0.05 μL．L-1; but a higher 1-MCP concentration at 0.2 μL．L-1 for a short duration (a half hour) was effective. In addition, pretreating Phal. amabilis with 0.1 μL．L-1 1-MCP for 12 hours was effective to inhibit 20 μL．L-1 ethylene from action. By pretreating Phal. amabilis with 0.8 μL．L-1 1-MCP for 8 hours on Day 0, followed by 2μL．L-1 ethylene fumigation for 12 hours on designate days, we found the residual protection of 1-MCP on Phal. amabilis was approximately 6-8 days. Furthermore, multiple applications of 1-MCP extended the duration of 1-MCP protection against ethylene. Three times applications increased the residual protection of 1-MCP on Phal. amabilis to at least 24 days.