葡萄延迟采收期间糖含量及其代谢酶活性的变化

对‘京秀’、‘亚历山大’以及‘京秀’ ב亚历山大’和‘京秀’ ב香妃’葡萄杂交后代群体的共20个单株成熟时及延迟采收期间浆果可溶性糖含量进行研究。结果表明, 延迟采收, 浆果内可溶性糖变化可分为积累型和相对稳定型两种。延迟采收3周, 糖积累型的‘京秀’和8个单株浆果可溶性糖显著积累, 蔗糖分解酶(酸性转化酶、中性转化酶、蔗糖合成酶分解方向) 活性持续升高, 而相对稳定型的‘亚历山大’和12个单株的糖与成熟时没有显著差异, 但酶活性急剧降低。果实成熟和延迟采收期间的呼吸速率也存在差异。成熟后延迟采收由蔗糖分解酶活性反映的浆果库力的大小和呼吸速率存在的差异可能是两种类型延迟采收期间糖含量存在差异的重要原因。

Changes in Soluble Sugars and Activities of Related Metabolic Enzymes in Grape Berries During Ripening and Delayed Harvest

Changes in soluble sugarswere studied during fruit ripening and delayed harvest in grape berries of J ingxiu, Alexander and 20 individuals of the cross p rogenies from two crosses: J ingxiu ×Alexander andJ ingxiu ×Xiangfei. Soluble sugars in the berry of Jingxiu and 8 individuals accumulated significantly duringthree-week delayed harvest period while no significant changes in soluble sugars were observed in Alexanderand the other 12 individuals. Acid invertase (AI) , neutral invertase (NI) , sucrose synthase ( cleavage direction) tended to increase during the delayed harvest period in J ingxiu and 97-2-23, which belonged to sugaraccumulation type, while those ofAlexander and 97-2-24, which were the sugar stable type, decreased significantly during the three weeks of delayed harvest. Moreover, there was difference in the resp iratory rate of berries between the two types. It is suggested that the difference in resp iratory rate and sink strength reflected bythe activities of sucrose degradation enzymes in berries may be an important factor in soluble sugar changesduring delayed harvest between the two types.