苹果果实发育过程中淀粉代谢和淀粉粒超微结构研究

苹果果实发育过程中,伴随果糖、葡萄糖和蔗糖的积累,淀粉含量经历了从低到高,又从高到低的变化。发育中后期,果实淀粉与可溶性糖呈现互为消长的变化。淀粉粒超微结构的变化表明,幼果期果肉细胞代谢旺盛,可观察到发育初期的造粉质体和大量的线粒体;发育中期是果实淀粉的主要累积期,整个造粉质体内充满淀粉;成熟期的果肉细胞呈现降解特征,淀粉粒大部分被降解,但淀粉粒表膜依然保持完整。还研究了淀粉代谢及淀粉粒超微结构变化与果实发育的关系。

Study on the Starch Metabolism and Ultrastructure of Starch Grain in Apple Fruit Development Process

The changes of starch metabolism and the ultrastructure of flesh parenchyma cell of'Starkrimson'apple fruit during fruit development process were studied.The results showed the soluble sugars,including fructose,glucose and sucrose accumulated gradually with fruit development.However,the starch content increased at the early stage and then decreased at the late stage.The ultrastructure study indicated that the vigorous metabolism in flesh parenchyma cell was embodied at young fruit stage,characterized by the numerous mitochondria and the initial developmental amyloplast.At the rapid growth stage,the amyloplasts were filled by starch.Moreover,the degenerating phenomenon was observed at the ripening stage,starch was degraded by amylase,but the outer membrane of starch grains remained intact.This article also discussed the relationship of starch metabolism,ultrastructure changes of starch grain with fruit development.