Shao M R, Jiang N, Li M, Howard A, Lehner K, Mullen J L, Gunn S L, McKay J K, Topp C N
Donald Danforth Plant Science Center, Saint Louis, MO, USA.
Department of Agricultural Biology, Colorado State University, Fort Collins, CO, USA.
Plant Phenomics. 2021 Nov 10;2021:9859254. doi: 10.34133/2021/9859254. eCollection 2021.
The root system is critical for the survival of nearly all land plants and a key target for improving abiotic stress tolerance, nutrient accumulation, and yield in crop species. Although many methods of root phenotyping exist, within field studies, one of the most popular methods is the extraction and measurement of the upper portion of the root system, known as the root crown, followed by trait quantification based on manual measurements or 2D imaging. However, 2D techniques are inherently limited by the information available from single points of view. Here, we used X-ray computed tomography to generate highly accurate 3D models of maize root crowns and created computational pipelines capable of measuring 71 features from each sample. This approach improves estimates of the genetic contribution to root system architecture and is refined enough to detect various changes in global root system architecture over developmental time as well as more subtle changes in root distributions as a result of environmental differences. We demonstrate that root pulling force, a high-throughput method of root extraction that provides an estimate of root mass, is associated with multiple 3D traits from our pipeline. Our combined methodology can therefore be used to calibrate and interpret root pulling force measurements across a range of experimental contexts or scaled up as a stand-alone approach in large genetic studies of root system architecture.
根系对于几乎所有陆地植物的生存至关重要，也是提高作物对非生物胁迫的耐受性、养分积累和产量的关键目标。尽管存在许多根系表型分析方法，但在田间研究中，最常用的方法之一是提取和测量根系的上部，即根冠，然后基于手动测量或二维成像进行性状量化。然而，二维技术本质上受到从单一视角获取的信息的限制。在这里，我们使用X射线计算机断层扫描来生成玉米根冠的高精度三维模型，并创建了能够从每个样本中测量71个特征的计算管道。这种方法改进了对根系结构遗传贡献的估计，并且足够精细，能够检测发育过程中根系结构的各种变化，以及由于环境差异导致的根系分布更细微的变化。我们证明，根拉力是一种高通量的根系提取方法，可以提供根系质量的估计，它与我们管道中的多个三维性状相关。因此，我们的综合方法可用于在一系列实验背景下校准和解释根拉力测量结果，或在根系结构的大型遗传研究中作为一种独立方法进行扩展应用。
