Sack F D, Suyemoto M M, Leopold A C
Boyce Thompson Institute for Plant Research, Cornell University, Ithaca, New York 14853, USA.
Am J Bot. 1986 Dec;73(12):1692-8.
Amyloplast sedimentation during gravistimulation and organelle movements was studied in living central rootcap cells of Zea mays L. cv. Merit. Cells from sectioned roots were viewed with a horizontally-mounted videomicroscope. The kinetics of gravity-induced amyloplast sedimentation were comparable to those calculated from experiments using fixed material. Individual amyloplasts fell at an average velocity of 5.5 micrometers min-1; the maximal velocity of fall measured was 18.0 micrometers min-1. Amyloplasts often rotated, sometimes rose in the cytoplasm, and occasionally underwent sudden rapid movements as fast as 58 micrometers min-1. Saltations of other organelles were frequently observed. This appears to be the first report of cytoplasmic streaming in the presumptive statocytes of roots.
研究了重力刺激过程中玉米（Zea mays L. cv. Merit）中央根冠活细胞中淀粉体的沉降和细胞器的运动。用水平安装的视频显微镜观察切片根中的细胞。重力诱导淀粉体沉降的动力学与使用固定材料的实验计算结果相当。单个淀粉体以平均5.5微米/分钟的速度下落；测量到的最大下落速度为18.0微米/分钟。淀粉体经常旋转，有时在细胞质中上升，偶尔会以高达58微米/分钟的速度突然快速移动。还经常观察到其他细胞器的跳跃现象。这似乎是关于根中假定平衡细胞中细胞质流动的首次报道。
