The Role of 1-methylcyclopropylene (1-MCP) and Salicylic Acid (SA) in Induced Resistance of Postharvest Fruits

Postharvest diseases cause huge postharvest losses of horticultural fresh produce. Cooling and synthetic fungicide are used as traditional postharvest preservation technology. Recently, induced resistance has been thought to be an optional and perhaps alternative preservation technology. 1-methylcyclopropylene (1-MCP) and salicylic acid (SA) are two more common chemical agents used mostly as a preservative for harvested fruit in order to achieve better quality and better taste. Many reports have also proven that 1-MCP and SA could induce postharvest fruit resistance. The purpose of this review is to summarize the role of 1-MCP and SA in postharvest fruit resistance, including the effect of 1-MCP and SA on the induced resistance as well as its involved mechanism; the effects of 1-MCP and SA on firmness, phenolic metabolism, membrane lipid metabolism, and reactive oxygen species in fruit after harvest; and the effects of 1-MCP and SA on disease resistance-related defense enzymes, proteins, signaling synthesis, and signaling pathways as well as the combined effect of 1-MCP and SA on the induced resistance and its mechanism. Meanwhile, we prospect for the future direction of increasing postharvest fruit resistance by 1-MCP and SA in more depth.