荔枝果实成熟期间糖积累和糖代谢相关酶活性变化

Changes of Sugar Accumulation and Enzyme Activity Related to Sugar Metabolism During Litchi Fruit Maturation

'糯米糍'和'淮枝'果实成熟期间假种皮中糖积累和糖代谢相关酶活性的变化规律表明,假种皮中的总糖、葡萄糖和果糖的含量,随成熟进程上升,蔗糖的变化是先升后降再回升;蔗糖合成酶(SS)和酸性转化酶(AI)的活性,表现为花后60d活性最高,随后下降,至采前1周维持在较低水平;'糯米糍'中糖含量以及SS和AI活性均较明显大于'淮枝'.据此推测,荔枝假种皮中AI和SS的活性高,蔗糖积累减少,单糖积累多,总糖含量因此提高.

The changes of sugar accumulation and related enzyme activities in sugar metabolism in aril during maturation of 'Nuomici'(abortedseeded) and 'Huaizhi'(normalseeded) fruit were studied. The results showed that the contents of total sugar, glucose and fructose ascended in the course of fruit maturation, while the change of sucrose content went up rapidly, then declined and lastly rose. The activities of sucrose synthase (SS) and acid invertase (AI) were the peak on the day 60 after anthesis, dropped after then, and kept lower levels within a week before fruit harvest. The sugar contents and the activities of SS and AI in aril of 'Nuomici' were higher than those in 'Huaizhi' during maturation. It was presumed that sugar metabolism was associated with the activities of AI and SS in litchi fruit. The higher SS and AI activities in aril were associated with the higher total sugar content caused by decreasing sucrose and increasing monosaccharides accumulation.