IAA、GA和ABA对葡萄果实^(14)C蔗糖输入与代谢的调控

Effects of IAA,GA and ABA on ^(14) C sucrose Import and Metabolism in Grape Berries

将 14 C蔗糖与激素IAA、GA和ABA同时通过果柄引入离体葡萄果实 ,研究了蔗糖积累代谢与激素的关系。结果表明 :①GA在幼果膨大期 ,IAA在果实始熟期以前 ,ABA从缓慢生长期到果实成熟 ,对蔗糖的吸收有明显促进效果。②GA与IAA在果实发育前期 (第Ⅰ、Ⅱ期 )可促进 14 C蔗糖转化为非醇溶性结构物 ;ABA则在成熟期表现出类似的作用。③IAA、GA与ABA在幼果膨大期可促进糖分转化为有机酸 ,但在缓慢生长期都抑制这一过程 ,抑制效果以ABA最显著 ,IAA其次 ,GA最小。成熟期糖分占醇溶物的 85 %～ 91% ,不同激素处理的差异不明显。ABA可促进各个时期果实中氨基酸的合成。④IAA可加快蔗糖分解为还原糖 ;GA增加果糖积累 ;ABA处理的果实蔗糖含量最高 ,推测ABA直接刺激了果肉维管束的蔗糖卸载。

C sucrose and plant growth regulators (IAA,GA and ABA)were simultaneously supplied to the excited grape berries( Vitis vinifera × V.labrusca, cv.kyoho)through the freshly cut pedicels.Hormonal regulation effects on sucrose accumulation and metabolism in grape berries at different developmental stages(Ⅰ,Ⅱ,veraison and Ⅲ)were studied.The results showed:① GA,IAA and ABA significantly facilitated 14 C sucrose import into the berries,respectively,at stage Ⅰ(young berry growth stage),stages Ⅰ and Ⅱ(growth lag stage),and stage Ⅱ and ripening phases.②The incorporation of 14 C sucrose into alcohol insoluble residues was enhanced by GA and IAA at stage Ⅰ and Ⅱ,while ABA did at stage Ⅲ.③IAA,GA and ABA promoted the transformation of 14 C sucrose into organic acid at stage Ⅰ,that significantly inhibited this transformation at stage Ⅱ.ABA promoted amino acid synthesis throughout the grape berry development.④The transformation of 14 C sucrose to reducing sugars was enhanced by IAA.GA increased the accumulation of fructose.Relative high content of sucrose was found with ABA treatments.It is supposed that ABA could directly facilitate sucrose unloading from the vascular bundle in grape berry.