采前喷施壳聚糖和油菜素内酯对葡萄采后落果的影响

Effects of Pre-harvest Application of Chiosan and Brassinosteroids on Reducing Grape Berries Abscission in Storage

以新疆无核白葡萄为试材,采前喷施油菜素内酯(BRs)和壳聚糖(CH),观察贮藏期葡萄落果率变化,并分析对葡萄品质和衰老相关酶活的影响。结果表明,两种处理在贮藏前期均能有效降低贮藏期葡萄落果率,壳聚糖效果好于油菜素内酯。二者均降低了果实酸度,提高了果实糖酸比,对果实总维生素C(抗坏血酸)含量没有影响,但明显提高了VC的还原度,使PG、POD和LOX等果实成熟衰老相关酶的活力高峰向后推迟了15～30天。推论BRs和CH可能是通过延迟无核白葡萄果实成熟衰老进程来减少落果,也暗示了无核白葡萄迅速的成熟可能是导致果实过早脱落的原因。

Brassinosteroids （BRs） and Chitosan （CH） were used to inhibit grape （Vitis vinifera L. cv. Wuhebai） berries abscission by preharvest treatment. In postharvest storage, fruit quality and age-related enzymes were analyzed.The result showed that, during the first 30 days, both treatments had reduced berries abscission rates. Compared with the control, total acid decreased and sugar/total acid ratio in treated berries was elevated; total ascorbic content remained stable, and the reduced state was increased. The polygalacturonase（PG）, lipoxyge nase （LOX） and peroxidase （POD） activity peak during storage time delayed for 15-30 days. It is suggested that BRs and CH could reduce the berries abscission through the retardment of ripening and senescing, and it also implied the rapid process of ripening maybe the reason of Wuhebai grape severe abscission phenomenon.