百合鳞茎发育和低温贮藏过程中淀粉粒亚显微结构的变化

以兰州百合(L ilium davidii var. unicolor) 鳞茎中部鳞片为试材, 利用扫描电子显微技术, 研究了鳞茎发育和低温贮藏过程中, 处于大维管束周围和大、小维管束中心位置的细胞内淀粉粒亚显微结构变化。结果表明: 栽种期大维管束周围细胞中有少量淀粉粒游离在细胞腔内, 并有絮状物存在。随着鳞茎的发育, 淀粉粒数量显著增加, 在植株半枯期达到最大, 形状由纺锤形逐渐变为近圆形; 处于大、小维管束中心位置的细胞, 淀粉粒数量明显少于大维管束周围细胞中淀粉粒数量, 并且在营养生长期和花蕾透色期, 淀粉粒表面有裂纹存在。低温贮藏过程中淀粉粒数量呈递减趋势, 在同一取样时期, 大、小维管束中心位置细胞内淀粉粒数目明显高于大维管束周围的细胞, 与鳞茎发育过程中的情况相反。

Changes in Ultra-structure of Starch Granule in the Middle Scales of Lilium Davidii var. unicolor During the Bulb Development and Storage at Low Temperature

Changes in ultra-structure of starch granules in the middle scales of Lilium davidii var.unicolor bulb were studied with the scanning electron microscope(SEM) during the bulb development and storage at low temperature.The results indicated that a few separate starch granules coexisted with floccules in the cell beside the big vascular bundle at planting stage.With the development of bulb,the amount of starch granules increased significantly and reached the maximum at the half withered stage.Furthermore,the shape changes were observed from spindle to almost rotundity.For the cells between the big and small vascular bundle,the amount of starch granules were smaller than that in the cells beside the big vascular bundle.And there are some cracks on the surface of the starch granule at the vegetative growth stage and bud autumn stage.During the storage at low temperature,the amount of starch granules tended to decline.By contrast with the process of bulb development,the amount of starch granules in the cells between the big and small vascular bundle were much more than that in the cells beside the big vascular bundle.