Thilakarathna Malinda S, Cope Kevin R
Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.
Biology and Microbiology Department, South Dakota State University, Brookings, SD, USA.
J Exp Bot. 2021 Jul 28;72(15):5285-5299. doi: 10.1093/jxb/erab198.
Split-root assays have been used widely in studies focused on understanding the complex regulatory mechanisms in legume-rhizobia symbioses, root nitrogen rhizodeposition, and belowground nitrogen transfer, and the effects of different biotic/abiotic factors on this symbiotic interaction. This assay allows a plant to have a root system that is physically divided into two distinct sections that are both still attached to a common shoot. Thus, each root section can be treated separately to monitor local and systemic plant responses. Different techniques are used to establish split-root assemblies, including double-pot systems, divided growth pouches, elbow root assembly, twin-tube systems, a single pot or chamber with a partition in the center, and divided agar plates. This review is focused on discussing the various types of split-root assays currently used in legume-based studies, and their associated advantages and limitations. Furthermore, this review also focuses on how split-root assays have been used for studies on nitrogen rhizodeposition, belowground nitrogen transfer, systemic regulation of nodulation, and biotic and abiotic factors affecting legume-rhizobia symbioses.
分根试验已广泛应用于各类研究，这些研究聚焦于理解豆科植物与根瘤菌共生关系中的复杂调控机制、根系氮素根际沉积及地下氮转移，以及不同生物/非生物因子对这种共生相互作用的影响。该试验使植物拥有一个根系，该根系在物理上被分为两个不同部分，但仍与同一个地上部分相连。因此，每个根段可以分别进行处理，以监测植物的局部和系统反应。建立分根装置使用了不同的技术，包括双盆系统、分隔生长袋、弯头根系装置、双管系统、中央有隔板的单个花盆或培养箱，以及分隔琼脂平板。本综述着重讨论目前在基于豆科植物的研究中使用的各类分根试验及其相关的优点和局限性。此外，本综述还关注分根试验如何用于氮素根际沉积、地下氮转移、结瘤的系统调控，以及影响豆科植物与根瘤菌共生关系的生物和非生物因子的研究。
