The effects of 1-methylcyclopropene on peach fruit (Prunus persica L. cv. Jiubao) ripening and disease resistance

In order to learn how 1-methylcyclopropene (1-MCP) affects ripening and disease-resistance of peach fruit (Prunus persica L. cv. Jiubao) after harvest, they were treated with 1-MCP and some were inoculated with Penicillium expansum. Treating peach fruit with 0.2 muL L-1 of 1-MCP at 22 degreesC for 24 h effectively slowed the decline in fruit firmness. The minimal concentration of 1-MCP able to inhibit fruit softening was 0.6 muL L-1. Changes in other parameters related to peach ripening, such as content of soluble solids, total soluble sugar, titratable acidity, soluble pectin and ethylene production were also significantly reduced or delayed by 1-MCP. Repeated treatment of peach with 1-MCP resulted in more effective inhibition of ripening. Post-harvest decay of peach fruit was reduced by treatment with 1-MCP and disease progress in fruit inoculated with P. expansum was reduced. The activities of phenylalanine ammonialyase, polyphenoloxidase and peroxidase in the inoculated fruit were also enhanced by 1-MCP.