Demonstration of osmotically dependent promotion of aerenchyma formation at different levels in the primary roots of rice using a 'sandwich' method and X-ray computed tomography
Demonstration of osmotically dependent promotion of aerenchyma formation at different levels in the primary roots of rice using a 'sandwich' method and X-ray computed tomography
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DOI：
10.1093/aob/mcs075
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发表时间：
2012-07-01
期刊：
影响因子：
4.2
通讯作者：
Mineyuki, Yoshinobu
中科院分区：
文献类型：
--
作者：
Karahara, Ichirou;Umemura, Konomi;Mineyuki, Yoshinobu
环境因子对水稻根通气组织形成的调控作用长期以来一直受到讨论，因为通气组织是在通气条件下组成性形成的。为了阐明这一问题，已经开发出一种独特的方法，该方法能够灵敏地检测两种不同环境条件下通气组织发育的差异。为了研究渗透胁迫对水稻根通气组织发育的影响，将萌发的水稻（Oryza sativa）颖果夹在两个琼脂平板之间，其中一个平板含有270 mm甘露醇，以检测同一根中有无甘露醇处理的通气组织的形成。根接触两个平板生长，从而单侧暴露于渗透胁迫。作为一种非侵入性方法，使用第三代同步加速器设备SPring-8（超级光子环8 GeV，日本同步辐射研究所）进行折射对比X射线计算机断层扫描（CT），用于可视化三维（3-D）水稻根部通气组织及其原位形成的完整结构。采用常规光学显微镜定量研究了甘露醇处理对通气组织发育的影响，并利用X射线CT对水稻初生根通气组织的结构连续性进行了三维和原位观察。光学显微镜和X射线CT显示，通气组织的发育促进了甘露醇处理一侧的根。详细的光学显微镜分析表明，沿沿着根轴从顶端到基部区域的横截面显示，通气组织发达显着接近根尖甘露醇处理的一侧的root.Continuity通气组织沿着水稻根轴的形态学证明了使用X射线CT。用Osandwich法测定了甘露醇促进水稻初生根通气组织的形成。
The effect of environmental factors on the regulation of aerenchyma formation in rice roots has been discussed for a long time, because aerenchyma is constitutively formed under aerated conditions. To elucidate this problem, a unique method has been developed that enables sensitive detection of differences in the development of aerenchyma under two different environmental conditions. The method is tested to determine whether aerenchyma development in rice roots is affected by osmotic stress.To examine aerenchyma formation both with and without mannitol treatment in the same root, germinating rice (Oryza sativa) caryopses were sandwiched between two agar slabs, one of which contained 270 mm of mannitol. The roots were grown touching both slabs and were thereby exposed unilaterally to osmotic stress. As a non-invasive approach, refraction contrast X-ray computed tomography (CT) using a third-generation synchrotron facility, SPring-8 (Super photon ring 8 GeV, Japan Synchrotron Radiation Research Institute), was used to visualize the three-dimensional (3-D) intact structure of aerenchyma and its formation in situ in rice roots. The effects of unilateral mannitol treatment on the development of aerenchyma were quantitatively examined using conventional light microscopy.Structural continuity of aerenchyma was clearly visualized in 3-D in the primary root of rice and in situ using X-ray CT. Light microscopy and X-ray CT showed that the development of aerenchyma was promoted on the mannitol-treated side of the root. Detailed light microscopic analysis of cross-sections cut along the root axis from the tip to the basal region demonstrated that aerenchyma developed significantly closer to the root tip on the mannitol-treated side of the root.Continuity of the aerenchyma along the rice root axis was morphologically demonstrated using X-ray CT. By using this osandwich' method it was shown that mannitol promoted aerenchyma formation in the primary roots of rice.