Ethylene as a Postharvest “Evil” and its Remedies in some Horticultural Crops

Abstract

Postharvest is an agricultural operation starting from the time of harvesting till the commodity reaches to the ultimate user/consumer. The postharvest life of horticultural produces is different from other produces in having shortest shelf life. In some horticultural crops which we call climacteric, there is an increase rate of respiration mainly due to a very high synthesis of the ripening hormone (ethylene), which has both beneficial and detrimental ("evil") effects depending on the type of commodity. The effect of ethylene is accumulative so continuous exposure to a low concentration of ethylene throughout marketing can cause significant harm. In climacteric fruits exogenous C2H4 caused the peel and flesh to ripen out of phase, with the flesh ripening faster than the peel. In a study of cut flowers, exposure to ethylene at 100 µl l -1 reduced vase life by about 30%. In order to minimize this evil effect different vase solutions have been investigated. STS (silver thiosulfate) and 1-MCP (1-methylcyclopropene) can effectively protect flowers against exogenous ethylene. Pre-treatment of plants with 1 µl l -1 1-MCP for 2 h completely inhibited ethylene-induced petal abscission. Applications of Silver thiosulphate (STS) and 1-MCP have a great role to withstand the impact of ethylene. Thus they give relief for those concerned with horticultural crops which are sensitive to ethylene action. However more researches have to be done about the level and time of application of these chemicals and a new chemical against ethylene should be investigated.