Studies On Postharvest Physiology And Storage Technology Of 'Black Amber' Plum Fruit

In this study, the effects of different storing temperature regimes and different fungicides and packaging materials on qualitative and physiological attributes of 'Black Amber' plum fruit were investigated. The parameters were studied, including firmness TSS TA total sugar vitamin C REC MDA POD SOD PG PE pectin and proline. The physiological mechanism of softening and senescence was discussed, which provided theoretical bases for the storage of 'Black Amber' plum fruit.In this study fruit stored under 20 ± 1 ℃ were ripened and the fruit on whole rottened quickly which leads to rapid decrease in the firmness, TA TSS, total sugar and vitamin C. Respiration rate and ethylene production of plum fruit followed typical climacteric pattern while REC of fruit tissues and MDA content increased sharply. POD, SOD, PG and PE activities and proline content showed climacteric changes. WSP content increased and protopectin content decreased quickly. Low temperature regime of 1 ± 1℃ significantly decreased respiration rate and ethylene production. It delayed the climacteric pathway and lowered the activities of PG and PE while the lower temperature delayed the increase of SOD activity, proline and protopectin contents. It inhibited the increase of WSP content, delayed the ripening and senescence of plum fruit but lower temperature tends to increase of POD activity. Comparing three different temperature regimes, fruits stored under 1 ± 1℃ exhibited optimum functions in terms of ripening and senescence as compared to 3 ± 1℃ and 5±1℃.Using different fungicides and packaging materials during storage at 1±1℃, compared with control, maintained higher firmness and delayed the decrease of the content of TA total sugar and vitamin C; apparently decreased respiration rate and ethylene production; delayed the increase of REC and decreased the accumulation of MDA, kept the membrane integrity; inhibited the increase of POD activity, maintained higher SOD activity, retarded the hydrolysis of protopectin and inhibited the increase of WSP, inhibited the activities of enzymes relating to fruits softening such as PG and PE; but the treatments had slightly effects on the content of TSS andproline. In addition, they could also reduced decay and browning of plum fruit, delayed the senescence of plum fruit and prolonged the storage timeThe intermittent warming treatment could significantly relieve browning of plum fruit but accelerate the decrease of firmness. In general the most conducive environment for the storing the plum fruits was 1 ?1癈 treated with fungicide No. 1 packed in special packages. Fruits stored for 60 days under such environment showed high quality attributes and 98 % fruits were graded as of good quality.