Rubinstein B
Michigan State University-Atomic Energy Commission, Plant Research Laboratory, Michigan State University East Lansing, Michigan 48823.
Plant Physiol. 1972 Apr;49(4):640-3. doi: 10.1104/pp.49.4.640.
Explants were isolated from 6-day-old etiolated bean seedlings (Phaseolus vulgaris L. cv. Black Valentine) containing the cotyledons with 4 mm of hypocotyl just below the node and/or the epicotyl. During incubation on distilled water, uneven growth of the hypocotyl or epicotyl occurred resulting in the formation of a hook. The more rapid growth of the side which became convex was not dependent upon the presence of the slower growing concave side. It was concluded that the main axis has an intrinsic capacity for asymmetric growth. The growth leading to hook formation was inhibited by alpha-naphthaleneacetic acid at concentrations above 0.2 milligram per liter.
外植体取自6日龄黄化菜豆幼苗（菜豆属普通菜豆品种黑瓦伦丁），包含子叶以及节点下方4毫米处的下胚轴和/或上胚轴。在蒸馏水中培养期间，下胚轴或上胚轴出现不均匀生长，导致形成弯钩。向外侧凸出一侧生长较快并不依赖于生长较慢的凹侧的存在。由此得出结论，主轴具有不对称生长的内在能力。浓度高于0.2毫克/升的α-萘乙酸抑制导致弯钩形成的生长。
