甘薯块根生长及其淀粉体发育过程的解剖结构特征  

Anatomical Structure of the Tuberous Root Growth and Its Amyloplast Development in Sweet Potato

作　　者：荆彦平[1] 李栋梁[1] 刘大同[1] 余徐润[1] 胡慕兰[1] 顾蕴洁[1] 王忠[1] 

机构地区：[1]扬州大学江苏省作物遗传生理重点实验室/农业部长江中下游作物生理生态与栽培重点开放实验室,江苏扬州225009

出　　处：《西北植物学报》2013年第12期2415-2422,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金(3107134,31270228);高等学校博士学科点专项科研基金(2009320004)

摘　　要：为了探明甘薯块根的生长及其淀粉体的发育规律,该试验以甘薯品种‘徐薯22’为材料,采用树脂半薄切片等方法对甘薯块根的生长及其淀粉体的发育进行观察研究。结果表明:(1)甘薯块根完成初生生长的时间短,块根初生结构由表皮、皮层和中柱构成,块根横截面上皮层所占比例比中柱大。(2)甘薯移栽后10d块根开始次生生长,次生生长形成维管形成层和木栓形成层;随着块根次生生长,位于次生木质部分散导管周围的薄壁细胞脱分化,通过平周分裂产生副形成层;维管形成层、木栓形成层和副形成层的共同作用使块根快速膨大。(3)淀粉体在块根进入次生生长时首先在皮层细胞产生,随后大量出现在次生生长产生的薄壁细胞中,块根中淀粉体的发生及发育总体上表现出由外向内的顺序。(4)块根薄壁细胞中的淀粉粒有单粒和复粒两种类型;块根生长早期,薄壁细胞中主要以复粒淀粉为主,生长后期主要以单粒淀粉为主;块根生长过程中,包含复粒淀粉的淀粉体可通过分裂形成包含单粒淀粉的淀粉体。(5)淀粉可在块根生长的整个时期积累,其中以块根生长中期积累速度最快。In order to make clear the regularity of tuberous root growth and amyloplast development in sweet potato, ‘Xushu 22’ was used as the material in this study. The tuber growth and amyloplast development were studied by using resin semi thin sections method. The experimental results showed that： （1）The primary growth of tuber with short duration time, the primary structure of tuber composed of epidermis, cortex and stele. The proportion of cortex on the cross section of tuber was bigger than that of stele. （2） The secondary growth of tuber started at 10 d after transplanting,the vascular cambium and the cork cambium formed in secondary growth. With the secondary growth, the parenchyma cells around the scattered vessel of secondary xylem dedifferentiated and formed accessory cambium by perielinal division. The vascular cambium, cork cambium and accessory cambium cooperated to make the tuber rapidly expanded. （3）The amyloplasts were first appeared in cortical cells as the secondary growth started. then appeared in large numbers in parenchyma cells which generated from secondary growth. The occurrence and development sequence of amyloplasts in tuber showed form outside to inside. （4）The starch granule in parenchyma ceils had two types, the single starch granule and the compound starch granule. The parenchyma cells were mainly composed of compound starch granule in early stage of development, while parenchyma cells were mainly composed of single starch granule in later stage. The amyloplast with compound starch granule could divide and formed the amyloplast with single starch granule. （5） The starch could accumulate at whole period of tuber growth and the fastest accumulation rate appeared in middle period of tuber growth.

关 键 词：甘薯 块根 淀粉体 增殖 生长 

分 类 号：Q944.54[生物学—植物学]