Efficacy of 1-MCP on controlling ethylene sensitivity and extending vase life of sensitive and less sensitive cut orchid flowers

This study was conducted to investigate the effects of 1-MCP on the sensitivity to ethylene and postharvest quality of selected cut orchid owers. Cut orchid owers are considered as the ethylene sensitive but there are apparently variation in sensitivity among species, cultivars and hybrids. Low effective concentration of 1-MCP and its minimum residues have caused that 1-MCP been viewed as an important and safe candidate for replacing STS. Inorescences of each Dendrobium ‘Darren Glory’ (DDG), D. ‘Sonia Bom’ (DSB), Mokara ‘Calypso Jumbo’ (MCJ) and M. ‘Chiti Gold’ (MCG) hybrids were purchased from a commercial farm. After harvest and transport to the Postharvest Lab they were divided into two groups and placed in two chambers. They exposed to 0 and 300 nL L-1 1-MCP for 4 hours. The chambers were opened for 1 hour airing. Then inorescences of each chamber divided to two subgroups and treated with 0 and 1 µL L-1 ethylene gas, balanced with nitrogen. After 24 hours the chambers were opened and the inorescences were taken out from them. The inorescences were kept in the laboratory with normal condition. The most weight loss and longest vaselife was recorded in DDG and MCG with 44% and 14 days respectively. Meanwhile, maximum postharvest quality improvement was obtained by 1-MCP pretreatment in very sensitive cut orchid hybrids.