采前喷施壳聚糖、壳寡糖对红地球葡萄贮藏品质和防御酶活性的影响

为探讨采前喷施壳聚糖、壳寡糖对红地球葡萄采后贮藏期果实品质及生理机制的影响,分别于采前30、20、10d对红地球葡萄果实进行500mg/L壳寡糖、500mg/L壳寡糖+1%乙酸、500mg/L壳聚糖+1%乙酸和清水对照处理。结果表明,采前喷施相同浓度的壳聚糖、壳寡糖均能显著降低葡萄贮藏期间的果实失重率、果柄抽干率和腐烂率,延缓果实硬度降低,提高果实的贮藏品质。能够保持过氧化氢酶(CAT)、过氧化物酶(POD)活性在较高水平上,并且明显提高了葡萄果实多酚氧化酶(PPO)、苯丙氨酸解氨酶(PAL)、β-1,3-葡聚糖酶(GUN)防御酶活性,使果实提高了自身抗性,延缓果实衰老。

Effects of pre-harvest spraying with chitosan and oligochitosan on storability and activity of defensive enzyme of post-harvest ’Red globe’ table grapes

Chitosan and oligochitosan were sprayed on the tree crown of ’Red globe’ table grapes before 30 d,20 d and 10 d for studying there effects on the fruit quality during storage time.The results showed that:All the application including 500 mg/L oligochitosan,500 mg/L oligochitosan with 1% acetic acid,500 mg/L chitosan with 1% acetic acid significantly decreased the weight loss rate,rachis appearance,rotten fruits rate.Moreover,Compared with the control,pre-harvest spraying with oligochitosan or chitosan could enhance the activities of the defense-related enzymes.i.e.,peroxidase(POD),catalase(CAT),polyphenol oxidase(PPO),phenylalanine ammonialyase(PAL) and β-1,3-glucanase(GUN),delay the quality deterioration during storage,and so effectively improved the grapes fruit quality and storability.Therefore,the results suggested that the enhanced disease resistance in harvested ’Red globe’ table grapes by oligochitosan or chitosan treatment could result from the activation of the disease-related defense system.