Effects Of Different Film Bag Packaging And Kadozan Treatment On Postharvest Physiology And Storage Behavior Of 'Jiefangzhong' Loquat Fruit

Loquat is originated in China.The main cultivation of loquat is region south of Yangtze.The fruit shape is round or ellipse,exocarp for yellow or orange,with hairs.Flavor is sweet and delicious,tender and juicy.Loquat fruits mature in summer with high temperature and humidity,so the strongly postharvest physiology leads to a sharp drop in the quality.In addition,the thin skin of loquat leads to uncertain risks during room temperature storage and transport.With the fruit of'Jiefangzhong' loquat,the chief loquat cultivar in Fujian Province as material,the effects of different film bag packaging and different concentrations of Kadozan treatment on its quality keeping and active oxygen metabolism during storage at(20±1)? were studied in this work.The main results were presented as follows:1.Effects of different packaging methods on postharvest quality and storage behavior of harvested ' Jiefangzhong' loquat fruit were discussed.Compared to PE film bag and the perforation film bag,micro-perforation film bag could inhibit the rise of disease index,respiration intensity,weightloss rate,and the accumulation of ethanol in pulp,help maintin higher nutrient content,exterior quality and the integrity of the structure of the cell membrane,thus to maintin higher commercial rate of loquat fruit.The results showed that for the effect of fresh-keeping storage of'Jiefangzhong loquat' fruit,the micro-perforation film bag was the best,then comes the perforation film bag,and the common PE film bag was the inferior.,then comes the perforation film bag,and the common PE film bag was the inferior.2.Effects of Kadozan treatment at different concentrations on postharvest quality and storage behavior of harvested 'Jiefangzhong'loquat fruit were investigated.Compared with control,Kadozan treatments at different concentrations could keep the postharvest quality of 'jiefangzhong' loquats.Furthermore,the treatment with 750-times dilution treatment was the optimal concentration,shown in delaying the postharvest loquat fruit disease index increase,maintaining highest commercially acceptable fruit percentage,lowering weight loss and respiration intensity,better maintaining fruit cell membrane integrity as well as such nutrient contents as total soluble solids,total sugar,acid,carotenoid and vitamin C.Thus,the 750-times dilution treatment of Kadozan can be the suitable processing condition to keep the loquat fruit quality storaged under(20±1)?.3.Effect of Kadozan treatment on reactive oxygen species(ROS)metabolism of harvested 'Jiefangzhong' loquat fruit was studied.The 750-times dilution treatment of Kadozan can delay the falling of'Jiefangzhong loquat' fruit pulp,ascorbic acid(AsA)and glutathione(GSH)endogenous antioxidant properties,maintained higher activities of ROS scavenging enzymes such as superoxide dismutase(SOD)catalase(CAT),and ascorbate peroxidase(APX).And the 750-times dilution treatment of Kadozan also effectively delayed the increase in the content of membrane lipid peroxidation product—malondialdehyde(MDA),induced a rapid increase in the production rate of superoxide anion radical(O2-·).The 750-times dilution treatment of Kadozan improved the ability of loquat fruit reactive oxygen removal,decreased the loquat fruit membrane lipid peroxidation.Therefore,the 750-times dilution treatment of Kadozan could enhance the ROS scavenging ability,reduce generation and accumulation of ROS,and decrease membrane lipid peroxidation.