The story of the introduction of the commercial use of 1-methylcyclopropene (1-MCP) is tightly linked with its beneficial effects in ethylene-sensitive ornamentals (Reid and Staby, 2007). Although the use of 1-MCP in apple storage now dwarfs its use in ornamentals, many of the strategies for commercial use were developed using ornamental models. Ornamentals provide a diversity of species and isolated petal and individual flower systems that can be used to test chemicals such as 1-MCP. Researchers have studied a range of ethylene-sensitive ornamental crops. Some wilt in response to ethylene, including orchids (Phalaenopsis), Hibiscus, stock (Matthiola incana; Celikel and Reid, 2002a) and carnation (Dianthus caryophyllus; Serek et al., 1995a, 1995b). Others respond to ethylene by abscising petals or florets, including Antirrhinum majus (Fig. 1), Alstroemeria, Penstemon, Rosa hybrida (Serek et al., 1995a), and wax flower (Chamelaucium uncinatum; Macnish et al., 2000). Potted plants studied include Begonia (Serek et al., 1995b), Kalanchoe blossfeldiana (Serek and Reid, 2000), Pelargonium peltatum (Cameron and Reid), Campanula carpatica (Sisler et al., 2004), and Lilium (Celikel et al., 2002).
Formulated as “EthylBloc,” (Floralife, Walterboro, SC) dextrin-bound 1-MCP is a very effective tool for overcoming the effect of ethylene in sensitive ornamentals, both cut flowers and potted plants (Celikel et al., 2002; Serek et al., 1995a). Despite its effectiveness, 1-MCP is not as widely used as it could be in the ornamentals industry. One major issue for producers of ornamental crops is the gaseous nature of the compound, which leads to practical difficulties in treatment. To address the need for a convenient treatment system, Floralife, the company that commercialized 1-MCP in North America, provides an “in–the-truck” treatment system. It comprises a bucket of water or mild alkali that is placed at the rear of the load and a water-soluble pouch containing the 1-MCP that is dropped into the bucket. The doors of the truck are closed, the bag dissolves, and sufficient 1-MCP is liberated to treat the flowers within the truck. Recently, the company has released a novel treatment system—1-MCP sachets resembling tea bags. The bags are dipped in water just before being placed within a packed box; the water diffuses through the bag, and the 1-MCP in it is released into the air within the box. Preliminary experiments have shown this technique to be quite effective (Staby, personal communication).
Among ethylene-sensitive flowers, carnations are perhaps the most studied (Borochov and Woodson, 1989). We previously used individual petals to examine the physiology of ethylene action in carnations (Mor and Reid, 1980). Not only are carnation flowers very sensitive to ethylene, but also the kinetics of the binding site in carnations have already been determined (Sisler et al., 1986). The kilodaltons for ethylene binding in petals was estimated to be 0.1 μL·L−1 and the concentration of binding sites was estimated to be 6.0 × 10−9 mol·kg−1. Application of inhibitors (Ag+ or 2,4-norbornadiene) inhibited ethylene binding by 20% to 80%.
In studies aimed at determining optimal conditions for commercial application of 1-MCP to cut flowers and potted plants, we used carnation petals as a model ethylene response system. We noted some curious aspects of the relationship among 1-MCP, ethylene, and temperature (Celikel and Reid, 2002b). The effectiveness of 1-MCP appeared to be strongly affected by the treatment temperature and was greatly reduced by the presence of ethylene during the treatment period. Neither of these results would be predicted by the current model of 1-MCP action. We report the results of further studies using this model system and suggest an alternative model to explain the inhibitory effects of 1-MCP.
CelikelF.G.DodgeL.L.ReidM.S.2002Efficacy of 1-MCP (1-methylcyclopropene) and promalin for extending the post-harvest life of Oriental lilies (Lilium × ‘Mona Lisa’ and ‘Stargazer’)Sci. Hort.93149155
CelikelF.G.ReidM.S.2002bAn alternative model for the inhibition of ethylene action by 1-methylcyclopropene (1-MCP)1921MencarelliF.SerraG.Techniche postraccolta dei prodotti ortoflorofrutticoliARSIA, Florence, Italy
HallA.E.FindellJ.L.SchallerG.E.SislerE.C.BleeckerA.B.2000Ethylene perception by the ERS1 protein in Arabidopsis Plant Physiol.12314491458
MacnishA.J.JoyceD.C.HofmanP.J.SimonsD.H.ReidM.S.20001-methylcyclopropene treatment efficacy in preventing ethylene perception in banana fruit and grevillea and waxflower flowersAust J. Exp. Agr.40471481
SerekM.SislerE.C.ReidM.S.1995b1-methylcyclopropene, a novel gaseous inhibitor of ethylene action, improves the life of fruits, cut flowers and potted plantsActa Hort.394337346
SislerE.C.ReidM.S.YangS.F.1986Effect of antagonists of ethylene action on binding of ethylene in cut carnationsPlant Growth Regulat.4213218
SislerE.C.SerekM.DupilleE.2004Comparison of cyclopropene, 1-methylcyclopropene, and 3,3-dimethylcyclopropene as ethylene antagonists in plantsPlant Growth Regulat.18169174
SislerE.C.SerekM.DupilleE.GorenR.1999Inhibition of ethylene responses by 1-methylcyclopropene and 3-methylcyclopropenePlant Growth Regulat.27105111