Infrared thermography has shown after roots of grasses freeze, ice spreads into the crown and then acropetally into leaves initially through vascular bundles. Leaves freeze singly with the oldest leaves freezing first and the youngest freezing later. Visualising the vascular system in its native 3-dimensional state will help in the understanding of this freezing process. A 2 cm section of the crown that had been infiltrated with aniline blue was embedded in paraffin and sectioned with a microtome. A photograph of the surface of the tissue in the paraffin block was taken after the microtome blade removed each 20 μm section. Two hundred to 300 images were imported into Adobe After Effects and a 3D volume of the region infiltrated by aniline blue dye was constructed. The reconstruction revealed that roots fed into what is functionally a region inside the crown that could act as a reservoir from which all the leaves are able to draw water. When a single root was fed dye solution, the entire region filled with dye and the vascular bundles of every leaf took up the dye; this indicated that the vascular system of roots was not paired with individual leaves. Fluorescence microscopy suggested the edge of the reservoir might be composed of phenolic compounds. When plants were frozen, the edges of the reservoir became leaky and dye solution spread into the mesophyll outside the reservoir. The significance of this change with regard to freezing tolerance is not known at this time.

中文翻译：

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通过染料浸润植物的块内成像从三个维度可视化冷冻对小麦维管系统的影响

红外热成像显示，在草根结冰后，冰扩散到冠部，然后最初通过维管束向顶部扩散到叶子中。叶子单独冻结，最老的叶子​​先冻结，然后最年轻的叶子冻结。在其原生 3 维状态下可视化血管系统将有助于理解这种冻结过程。将已用苯胺蓝浸润的 2 cm 的牙冠切片包埋在石蜡中并用切片机切片。在切片机刀片移除每个 20 μm 切片后拍摄石蜡块中组织表面的照片。将 200 到 300 张图像导入 Adob​​e After Effects，并构建苯胺蓝染料渗透区域的 3D 体积。重建显示，根部进入了功能上在树冠内部的一个区域，该区域可以作为一个水库，所有的叶子都可以从中汲水。给单根灌染染料溶液时，整个区域充满染料，每片叶子的维管束都吸收染料；这表明根的维管系统没有与单叶配对。荧光显微镜表明储层的边缘可能由酚类化合物组成。当植物被冷冻时，水库的边缘会渗漏，染料溶液会扩散到水库外的叶肉中。这种变化对耐冻性的意义目前尚不清楚。整个区域充满染料，每片叶子的维管束都吸收了染料；这表明根的维管系统没有与单叶配对。荧光显微镜表明储层的边缘可能由酚类化合物组成。当植物被冷冻时，水库的边缘会渗漏，染料溶液会扩散到水库外的叶肉中。这种变化对耐冻性的意义目前尚不清楚。整个区域充满染料，每片叶子的维管束都吸收了染料；这表明根的维管系统没有与单叶配对。荧光显微镜表明储层的边缘可能由酚类化合物组成。当植物被冷冻时，水库的边缘会渗漏，染料溶液会扩散到水库外的叶肉中。这种变化对耐冻性的意义目前尚不清楚。水库的边缘开始渗漏，染料溶液扩散到水库外的叶肉中。这种变化对耐冻性的意义目前尚不清楚。水库的边缘开始渗漏，染料溶液扩散到水库外的叶肉中。这种变化对耐冻性的意义目前尚不清楚。