Effects of ethylene and 1-MCP treatment on postharvest quality and preservation of ‘Jinfeng’ kiwifruit

Objective This study aims to systematically analyze the effects of ethylene and 1-methylcyclopropene （1-MCP） treatments on the postharvest quality of ‘Jinfeng’ kiwifruit and evaluate their preservation effects，thereby providing a scientific basis and technical support for improving the postharvest storage and preservation technology system of this cultivar. Method ‘Jinfeng’ kiwifruit was used as test materials.Under ambient temperature （20±1）℃ storage conditions，and based on dynamic changes in fruit firmness （five stages：8-10，6-8，4-6，3-4，and <3 kgf/m²），25 μL/L ethylene and different concentrations of 1-MCP （0.25，0.5，0.75，and 1.0 μL/L） were applied respectively，and the effects of different treatment combinations on postharvest fruit quality were observed and compared. Result The results show that 1-MCP treatment can effectively delay the decline in fruit firmness of ‘Jinfeng’ kiwifruit at different firmness stages：in Stage 1 （8-10 kgf/m²），the firmness of the CK group was lower than that of the E0.5M and E0.25M treatments from the 8th day onward，with the E0.25M treatment group showing the highest soluble solids content （17.5%） on the 12th day，soluble sugar content reaching 13.27%，titratable acid content at 0.48%，vitamin C content peaking at 193.48 mg/100g during the soft-ripe period，and sensory evaluation superior to other groups；in Stage 2 （6-8 kgf/m²），from the 8th day，the firmness of the CK group was lower than that of the E0.25M and E1.0M treatments，with E0.25M showing the best effect，as this group had a soluble solids content of 16.59% on the 8th day （higher than other groups），and during soft-ripening，its soluble sugar （14.52%），titratable acid （0.48%），and vitamin C （175.72 mg/100g） contents were superior，with the best taste；in Stage 3 （4-6 kgf/m²），the E0.5M treatment group reached the edible state ［（2±0.5） kgf/m²］ on the 10th day，4 days longer than the CK group，with soluble solids content increasing to 17.35%，while during soft-ripening，the E0.25M group had the highest soluble sugar （9.67%），titratable acid （0.56%），and vitamin C （169.53 mg/100g） contents among all treatments；in Stage 4 （3-4 kgf/m²），the firmness of the CK group was consistently lower than that of all 1-MCP treatments，with the E0.5M group showing a slower firmness decline from the 6th to 10th day，soluble solids content maintaining an upward trend，and the best taste evaluation；in Stage 5 （<3 kgf/m²），the CK and E0.25M groups had a short edible window （4 days），while the E0.5M group extended this window by 4 days compared to the CK group and maintained high soluble sugar，titratable acid，and vitamin C contents；overall，the E0.25M treatment was optimal for firmness ranges of 8-10 kgf/m² and 6-8 kgf/m²，while the E0.5M treatment was most effective for stages of 4-6 kgf/m²，3-4 kgf/m²，and <3 kgf/m². Conclusion Under ambient storage conditions，exogenous ethylene treatment significantly promotes the fruit softening process of ‘Jinfeng’ kiwifruit，with ethylene-treated fruits reaching the edible state within 4-6 days after treatment，2-4 days earlier than the CK group；applying 1-MCP before the fruit respiratory climacteric not only effectively delays the post-ripening softening process of ‘Jinfeng’ kiwifruit but also extends fruit shelf life and maintains its excellent quality，and these findings provide important theoretical support and practical guidance for developing new postharvest preservation technologies for ‘Jinfeng’ kiwifruit.