| In this paper,kiwifruit(Actinidia deliciosa.cv.Bruno)were treated with 0(as Control),0.5 and 1.0 μL/L 1-methylcyclopropene(1-MCP)for 24 h,and then stored at room temperature(20 ℃).The effect of 1-MCP on the quality,ethanol metabolism and volatile components in fruit were investigated during storage.The main results were as follows:1.1-MCP treatment had benefited to maintain the fruit quality during storage,as 1-MCP treatment effectively delayed the decrease in the firmness of fruit,inhibited the increase rate of soluble solid content(S SC)and the decrease rate of titratable acid(TA)and reduced fruit decay,which indicated that 1-MCP treatment delayed the ripening process and maintained quality in kiwifruit during postharvest.2.0.5 μL/L and 1.0 μL/L 1-MCP treatment decreased respiration rate and the increase rate of pyruvic acid,inhibited the accumulation of acetaldehyde and ethanol,and also effectively decreased the activities of enzymes involved in ethanol metabolism,including pyruvate decar-boxylase(PDC)and alcohol dehydrogenase(ADH),and their relative expression of genes.Compared to 0.5 μL/L 1-MCP treatment,1.0 μL/L 1-MCP treatment was more efficient on controlling the accumulation of ethanol.It was suggested that application of optimum concentration of 1-MCP could significantly reduce the accumulation of ethanol and acetaldehyde,and then contributed to inhibition of the off-flavor in kiwifruit during postharvest.3.Esters was the major volatile components in kiwifruit,and 1-MCP treatment significantly changed the composition of volatile substances in kiwifruit during storage.1-MCP treatment significantly inhibited the increase in the quantity and the relative content of esters and the decrease of the relative contents of aldehydes and alcohols.In addition,1-MCP treatment significantly increased the proportion of aldehydes,ketones and alcohols in fruits,and resulted in the accumulation of alcohols and aldehydes and ketones.The reason might be that 1-MCP treatment inhibited the accumulation of acetaldehydes and ethanols,so that the concentration of acetaldehydes and ethanols in fruit could not reach a certain threshold,and inhibited the conversion of aldehydes,alcohols and other volatile substances.Both 1-MCP treatments showed an inhibitory effect on the content of volatile components,but the content of volatile components of 0.5 μL/L 1-MCP treatment was higher than that of 1.0μL/L 1-MCP treatment. |
