葡萄果实始熟期前后糖和pH值及ABA变化

Changes of Sugar,pH and ABA around the Onset of Grape Berry Ripening

以玫瑰香(Vitis vinifera L. cv. Muscat Hamburg)葡萄为试材,研究果实纵横径,始熟期前后pH值、可溶性糖、总酸和脱落酸含量的变化。结果表明,玫瑰香葡萄果实纵横径变化趋势基本一致,分第一个快速生长期、缓慢生长期、第二个快速生长期三个时期,果实内可溶性糖主要为葡萄糖和果糖,蔗糖含量很少。可溶性糖含量在始熟期开始快速上升,三种糖变化趋势基本一致。葡萄糖、果糖和蔗糖始熟期前平均日增量分别为0.29,0.23,0.01 mg/g,始熟期后三者平均日增量分别为1.35,1.67,0.12 mg/g。始熟期前果实内葡萄糖∶果糖为12∶1,始熟期后葡萄糖和果糖含量开始快速升高,果糖升高速率高于葡萄糖,到花后77 d,二者差距逐渐缩至葡萄糖∶果糖为1∶1。pH值在始熟期开始快速升高,总酸含量和pH值呈吻合相反变化趋势。脱落酸含量伴随始熟的发生而迅速增加,果实成熟阶段有一个高峰,完熟前下降。总之,随着花后56 d葡萄果实成熟的启动,可溶性糖含量(主要葡萄糖和果糖)、pH值和ABA水平开始快速上升。葡萄果实成熟的启动依赖于ABA峰出现,而果实完熟过程不依赖于ABA的积累。葡萄果实始熟期前后可溶性糖含量、pH值和ABA水平之间平行关系调控的生理机制,即ABA持续积累的生理机制是今后研究的重要内容。

The changes of berry length, diameter, pH value, soluble sugar, total acid and ABA contents in Muscat Hamburg grape （vitis vinifera L. ） around the onset of grapeberry fruit ripening were observed. The main results showed that the soluble sugar, including more glucose and fructose, as well as less sucrose, increased rapidly before veraison, and having similar trend. The average daily increment of glucose, fructose and sucrose varied from 0.29mg/g, 0.23mg/g; 0.01mg/g before veraison to 1.35mg/g, 1.67mg/g, 0.12mg/g after veraison, respectively. The ratio of glucose/fructose before veraison was 12 ： 1, and both increased rapidly at veraison. The rate of increment of fructose was higher than that of glucose, finally the ratio of glucose/fructose was I ： 1 at 77 days after flowering. At and after veraison, pH value increases rapidly, having opposite changing trend with total acid content. Similarly, ABA content increased rapidly coupling with veraison, and having a peak at two weeks after veraison, then declined during complete ripening. Conclusively, soluble sugar content 1, pH value and ABA levels all began to increase rapidly at 56 days after flowering （namely at veraison）. The grapeberry ripening was coindent with the appearance of ABA peak, while the fruit post-ripening was not dependent on the accumulation of ABA. The physiologically regulated mechanisms of the parallel relationship for soluble sugar content, pH value and ABA level, namely the core question about the physiological mechanism of the accumulation of ABA at veraison, was an important research field in future.