Belzile François, Seck Waldiodio, Sanghera Prabhjot, Han Liwen, Dutilleul Pierre
Département de Phytologie, Faculté des Sciences de l'Agriculture et de l'Alimentation (FSAA), Université Laval, Québec, QC G1V 0A6, Canada.
Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6, Canada.
Plants (Basel). 2024 Nov 29;13(23):3369. doi: 10.3390/plants13233369.
Typically, root system architecture (RSA) is not visible, and realistically, high-throughput methods for RSA trait phenotyping should capture key features of developing root systems in solid substrates in 3D. In a published 2-D study using thin rhizoboxes, vermiculite as a growing medium, and photography for imaging, triplicates of 137 soybean cultivars were phenotyped for their RSA. In the transition to 3-D work using X-ray computed tomography (CT) scanning and mineral soil, two research questions are addressed: (1) how different is the soybean RSA characterization between the two phenotyping systems; and (2) is a direct comparison of the results reliable? Prior to a full-scale study in 3D, we grew, in pots filled with sand, triplicates of the Casino and OAC Woodstock cultivars that had shown the most contrasting RSAs in the 2-D study, and CT scanned them at the V1 vegetative stage of development of the shoots. Differences between soybean cultivars in RSA traits, such as total root length and fractal dimension (FD), observed in 2D, can change in 3D. In particular, in 2D, the mean FD values are 1.48 ± 0.16 (OAC Woodstock) vs. 1.31 ± 0.16 (Casino), whereas in 3D, they are 1.52 ± 0.14 (OAC Woodstock) vs. 1.24 ± 0.13 (Casino), indicating variations in RSA complexity.
通常情况下，根系结构（RSA）是不可见的，实际上，用于RSA性状表型分析的高通量方法应能捕捉到固体基质中三维发育根系的关键特征。在一项已发表的二维研究中，使用薄根箱、蛭石作为生长介质，并通过摄影进行成像，对137个大豆品种的RSA进行了三次重复的表型分析。在向使用X射线计算机断层扫描（CT）和矿质土壤的三维研究过渡时，解决了两个研究问题：（1）两种表型分析系统对大豆RSA的表征有多大差异；（2）结果的直接比较是否可靠？在进行全面的三维研究之前，我们在装满沙子的花盆中种植了在二维研究中表现出最显著对比RSA的Casino和OAC Woodstock品种的三份重复样本，并在地上部营养生长的V1阶段对其进行了CT扫描。在二维中观察到的大豆品种在RSA性状上的差异，如总根长和分形维数（FD），在三维中可能会发生变化。特别是，在二维中，平均FD值为1.48±0.16（OAC Woodstock）对1.31±0.16（Casino），而在三维中，它们为1.52±0.14（OAC Woodstock）对1.24±0.13（Casino），这表明RSA复杂性存在差异。
