Studies on the mechanism of the occurrence of hollow root in 'Gensuke'

《玄助》空根发生机制研究

基本信息

批准号：
62560035
负责人：
KANO Yasutaka
金额：
$ 1.41万
依托单位：
Ishikawa Agricultural College
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1989
项目状态：
已结题

项目摘要

Gensuke daikon has been cultured in the sand dune regions of Ishikawa Prefecture because of its high quality. When the radish is sown in midsummer, "hollow root" which has lengthwise hollow in the central part of the root has been frequently observed. This research was carried out to elucidate the mechanism of the occurrence of hollowness in the root.When Gensuke was cultivated under high temperature or treated with high concentration of auxin from sowing to 30 days after sowing, root growth during that period was severely suppressed with high occurrence of hollow root. The occurrence of hollow root was high when the rate of weight growth by divided the root weight on the 60th day after sowing by that oh 30th day was large, but the occurrence was low when the rate was small. In this cash, vessels in the root bifurcated rapidly in the former, but the space among vessels was small in the latter. This result shows that root growth is accelerated by the active proliferation of parenchymatous cells in the former, but the growth is suppressed by the poor proliferation of the cells in the latter.The lysigenous intercellular space developed to the hollow with rapid root growth. The space would not develop to the hollow under the suitable condition because the space continued to be filled up with parenchymatous cells, but the space developed to the hollow under the unsuitable condition because the space could not be filled up with the cells owing to the poor proliferation of the cells.In cultivars resistant to hollowness the proliferation of parenchymatous cells was not suppressed even under high temperature, hollow root did not occur as the lysigenous intercellular space continued to be filled up with the cells.Summing up these results, whether or not the lysigenous intercellular space develops to hollow is decided by the balance between the degree of development of the lysigenous intercellular space and the degree of the filling of the space by parenchymatous cells.

石川县的沙丘地区一直在石川县的沙丘地区种植源助萝卜，因为其品质优良。盛夏播种萝卜时，经常会出现根部中央部分呈纵向空心的“空心根”现象。本研究旨在阐明根部空心发生的机制。当Gensuke从播种到播后30天进行高温栽培或用高浓度生长素处理时，该时期的根系生长受到严重抑制，出现空根现象。播种后第60天根重除以第30天根重的重量增长率大时，空心根的发生率高；比率小时，空心根发生率低。在这种现金中，前者根部的血管迅速分叉，但后者的血管之间的空间很小。结果表明，前者的薄壁细胞增殖活跃，促进了根的生长，而后者的细胞增殖不良，则抑制了根的生长。溶源细胞间隙发育为中空，根生长迅速。在合适的条件下，空间不会发展成中空，因为空间继续被薄壁细胞充满，但在不合适的条件下，空间发展成中空，因为空间差，不能被细胞充满。抗空心品种，即使在高温下，薄壁细胞的增殖也不受抑制，细胞不断充满溶源细胞间隙，不发生空心根。由此可见，溶源性细胞间隙是否发育为中空，取决于溶源性细胞间隙的发育程度与薄壁细胞对该间隙的填充程度之间的平衡。