Effect Of Harvest Date, Storage Temperature And Chitosan Treatment On Storage Of Nanfeng Mandarin Fruits

Citrus is the most important fruit in the world. Nanfeng mandarin, a local citruscultivar which has more than1300years of history in Jiangxi province, is famous at homeand abroad for its tender, juicy flesh, concentrated sweet flavor and favorite aroma. Withfurther increase of cultivation area and yield of Nanfeng mandarin, postharvestpreservation of fruits is particularly important, which become a current urgent problem tobe solved.In this study, Nanfeng mandarin97-2and97-1fruits were used as test materials, theeffect of different harvest date and storage temperature on postharvest physiology and fruitquality were investigated in order to determine the best shelf life of fruits. Meanwhile, theeffect of chitosan coating on fruit quality and storability of Nanfeng mandarin97-2wasalso studied. The main results are as follows:1. Nanfeng mandarin fruits were stored at5±1℃and RH85%-90%, the resultsshowed that decay rate of harvest Ⅰ and Ⅱ (185,195days after blooming, DAB) fruitswere0%and11%respectively, which significantly lower than harvest Ⅲ (205DAB)fruits (28%) at110d of storage, but weight loss rate of harvest Ⅰ fruits was11.28%,which significantly higher than harvest Ⅱ and Ⅲ. The fruits of harvest Ⅰ and Ⅱ hadless MDA accumulation, lower respiration rate and PPO activity than harvest Ⅲ, thuseffectively delayed the reduction of Vc and TA. According to the physiological andbiochemical indexes, the storage quality of harvest Ⅱ was better than harvest Ⅰ and Ⅲ,was the most suitable harvest date for storage of Nanfeng mandarin.2. Nanfeng mandarin fruits were stored at three different temperature (4,7and10℃)for90d. Compared with other two temperature, the fruits stored at4℃had lower decayrate and weight loss rate, maintained higher quality, had less MDA accumulation and PPOactivity, which indicated4℃was the most suitable temperature for storage of Nanfengmandarin.3. Nanfeng mandarin fruits were stored the different temperature and transferred toshelf (20±1℃, RH85%-90%) after30d,60d and90d of storage respectively, theresults showed that fruits stored at4±1℃had lower decay rate and obtained better fruitquality during shelf life after60d of storage, was a more appropriate shelf life.4. At room temperature, chitosan coating could delay appear of rotten fruit, and2.0%chitosan coating treatment could maximum reduce weight loss rate, reduce the decay rate,delay the reduce of TSS, TA and total sugars content, inhibit respiration rate and MDAaccumulation of fruits during storage, as well as induce the activity of PAL, enhanceresistance of fruit to postharvest diseases. The above results indicated that chitosan coatinghad better effect on the storage quality of Nanfeng mandarin fruits.