摘要
目前关于植物器官着色的生化代谢途径及其调控等已有深入了解,而关于色素积累的细胞学过程研究还十分缺乏。本研究以目前红肉猕猴桃主栽品种‘红阳’为试验材料,通过光学显微镜及透射电子显微镜观察了该红肉猕猴桃果实内果皮横剖面着色组织的解剖特征,并描述了花青素体的细胞学特征。结果表明,‘红阳’果实中色素体的形成及着色细胞分布存在组织特异性。首次在猕猴桃果实中观察到2种花青素体形态,一种是规则的圆形色素体,另一种是小颗粒色素体;本研究还观察到花青素色素体载体的形态特征及其解体与液泡化过程。‘红阳’猕猴桃开花后30 d时,果实内果皮的圆形色素体出现在维管束及其周围的小细胞里,开花后68 d,小颗粒色素体开始在大的薄壁细胞里出现;在花后117 d,维管束及其周围小细胞仍在形成大量色素体颗粒。通过电镜观察表明,在这个时期的内果皮薄壁细胞中可以观察到大量的色素体载体(AVI carriers),这些载体内存在多种不同形态的色素体,可能反映了薄壁细胞的着色过程。有的色素体仍呈现圆形,有的呈现新月形或者其它不规则形,总体上载体内的这些色素体变得越来越小且越来越不规则,最终导致色素体载体不同程度的液泡化。这些结果暗示了红肉猕猴桃果实色素体的形成部位、细胞学形态特征以及色素体的解体与花青素释放过程,表现了"移位释放"的特点。
Although the biosynthetic pathways for anthocyanins and their regulation have been well studied, the cytology of anthocyanin accumulation is still less understood. Here, we used light and electron microscopy to investigate the anatomical features in pigmented inner pericarp of ＇Hongyang＇, the mainly cultivated red kiwifruit in China, and to describe the cytological morphology of anthocyanoplasts. The results showed anthocyanoplasts and pigmented celts were formed in specific tissues. It was firstly observed that there are two forms of antho- cyanoplasts, one is vesicle-like pigment bodies, and the other is the smaller intensely pigmented granule. Mor- phology, degradation and vacuolarization of anthocyanoplasts carriers （or anthocyanic vacuolar inclusions carriers） were also observed. Vesicle-like pigment bodies appeared in the small cells of vascular traces and its adjacent cells （VTs） in inner pericarp of ＇Hongyang＇ at 30 days after flowering （DAF）. In addition, at 68 DAF, smaller intensely pigmented granules were found in the bigger septum-originated parenchymatous cells （SEP）. Anthocyanoplasts were kept in VTs at 117 DAF. Under electron microscopy, plenty of anthocyanoplasts carriers were observed in the bigger parenchymatous cells. Anthocyanoplasts in the carriers were showed to have multiple forms that re- flected the coloration of the parenchymatous cells between each of two septums. Some were still keeping round, some were crescent-shaped, but others seemed to change to irregular. In general, those anthocyanoplasts became smaller and more irregular, and finally leaded to vacuolarization of the carriers to different extents. Our results described the positions of anthocyanoplasts formation and their cytological features. It was suggested that the col- oration of ＇Hongyang＇ inner pericarp was attributable to anthocyanin release after the anthocyanoplasts shift from VTs to SEP.
出处
《安徽农业大学学报》
CAS
CSCD
北大核心
2012年第5期702-706,共5页
Journal of Anhui Agricultural University
基金
国家自然科学基金项目(3067143
31171945)资助
关键词
红肉猕猴桃
'红阳’
花青素体
色素体载体
液泡化
red-fleshed kiwifruit
＇Hongyang＇
anthocyanoplasts
anthocyanoplasts carriers
vacuolarization
