九仙蜜桃室温贮藏过程中果实品质及抗氧化酶系统的变化

以九仙蜜桃的离核和粘核两品系为材料,研究其在室温贮藏过程中果实硬度、果实腐烂率、果皮颜色、果皮中叶绿素和类胡萝卜素含量、果实品质、丙二醛(MDA)含量、超氧化物歧化酶( SOD)、过氧化物酶( POD)和过氧化氢酶(CAT)活性的变化.结果表明,在贮藏第12天,离核果实硬度为粘核果实的45.28%;果实腐烂率比粘核高51%;果实中可溶性固形物含量离核和粘核分别增加了35.1%和30.8%;总糖含量离核增加了38.6%,粘核增加了30.0%,而可滴定酸含量整体呈下降趋势.果实中MDA含量离核和粘核分别比贮藏初期增加了60.6%和25.1%,与离核果实相比,粘核果实SOD、POD、CAT活性的高峰期出现较迟,并在贮藏后期保持了较高的活性,从而提高了其耐贮性.

Changes of fruit qualities and antioxidant enzyme system in two varieties of Jiuxian peach during storage at room temperature

To investigate the storage characters of freestone and clingstone varieties of Jiuxian peach at room temperature, dynamic changes in firmness, decay rate, peel color parameters, contents of chlorophyll and carotenoid in peel, fruit qualities, malondialdehyde content (MDA), activity of superoxide dismutase (SOD), peroxidase(POD) and catalase (CAT)were studied. The results showed that at twelfth day of the storage, the firmness of freestone is 45.28% of that of clingstone; decay rate of freestone is 51% higher than that of clongstone;total slouble solid in freestone and clingstone incrased by 35.1% and 30.8%, and total sugar in freestone and clingstone increased by 38.6% and 30.0%, respectively, but contents of titratable acid decreased during the whole storage period. MDA content in freestone and clingstone fruit increased by 60.6% and 25.1% at the end of storage compared with the beginning of storage. The peak of activities of SOD, POD and CAT in clingstone fruit were delayed in comparison with that in freestone fruits and kept at higher levec which delayed its senescence and maintained its fruit qualities.