Pérez-Torres Eduardo, Kirchgessner Norbert, Pfeifer Johannes, Walter Achim
Institute of Agricultural Sciences, ETH Zurich, 8092, Zurich, Switzerland.
Plant Cell Environ. 2015 Nov;38(11):2318-26. doi: 10.1111/pce.12548. Epub 2015 Jun 4.
The formation and development of belowground organs is difficult to study. X-ray computed tomography (CT) provides the possibility to analyse and interpret subtle volumetric changes of belowground organs such as tubers, storage roots and nodules. Here, we report on the establishment of a method based on a voxel dimension of 240 μm and precision (standard deviation) of 30 μL that allows interpreting growth differences among potato tubers happening within 3 h. Plants were not stressed by the application of X-ray radiation, which was shown both by morphological comparison with control plants and by analysis of lipid peroxidation as a measure of oxidative stress. Diel (24 h) tuber growth fluctuations of three potato genotypes were monitored in soil-filled pots of 10 L. In contrast to the results from previous reports, most tubers grew at similar rates during day and night. Tuber growth was not related to the developmental stage of plants and tubers. Pronounced differences were observed between average growth rates in different tubers within a plant. These results are discussed in the context of restrictions of past methods to study tuber growth and in the context of their potential for the characterization of the formation and development of other belowground plant organs.
地下器官的形成与发育很难进行研究。X射线计算机断层扫描（CT）为分析和解读诸如块茎、贮藏根和根瘤等地下器官的细微体积变化提供了可能。在此，我们报告一种基于体素尺寸为240μm且精度（标准差）为30μL的方法的建立，该方法能够解读3小时内发生的马铃薯块茎之间的生长差异。通过与对照植株进行形态学比较以及分析脂质过氧化作为氧化应激的一种度量方式，结果表明施加X射线辐射并未使植株受到胁迫。在10升装满土壤的花盆中监测了三种马铃薯基因型块茎的昼夜（24小时）生长波动情况。与之前报告的结果相反，大多数块茎在白天和夜晚的生长速率相似。块茎生长与植株和块茎的发育阶段无关。在一株植物的不同块茎之间观察到了明显的平均生长速率差异。我们结合过去研究块茎生长方法的局限性以及这些方法在表征其他地下植物器官的形成与发育方面的潜力来讨论这些结果。
