IMP 2 RIS, an automated plant root PET radiotracer gas delivery system for in-soil visualization of symbiotic N 2 fixation in nodulated roots of soybean plants via PET imaging.

Abstract

The real-time and non-invasive visualization and quantification of symbiotic nitrogen fixation (SNF) in nodulated roots of soybean plants using Positron Emission Tomography (PET) imaging, coupled with the application of [ 13 N]N 2 gas as a PET radiotracer, has been explored in only a few studies. In these studies, [ 13 N]N 2 was delivered to nodulated soybean roots suspended in air within gas-tight acrylic boxes, followed by two-dimensional (2D) PET imaging to visualize the assimilated [ 13 N]N 2 in the air-suspended root nodules. In this paper, we introduce the In-Media Plant PET Root Imaging System (IMP 2 RIS), a novel gas delivery system designed and constructed in-house. Unlike the previous methods, IMP 2 RIS allows for non-intrusive delivery and exposure of [ 13 N]N 2 gas to the nodulated roots of soybean plants grown in a clay-rich, soil-like and visually opaque growth medium. This advancement enabled in-soil, three-dimensional (3D) visualization of SNF in soybean root nodules using Sofie, a preclinical PET scanner. Equipped with automated controls, IMP 2 RIS ensures ease of operation and operator safety during the [ 13 N]N 2 delivery process. We describe the components and functionalities of IMP 2 RIS, supported by experimental results showcasing its successful application in efficient delivery and exposure of [ 13 N]N 2 gas to nodulated roots of three soybean plant cultivars that vary in rates of N 2 fixation. The in-soil quantitative PET imaging of SNF, aided by IMP 2 RIS, holds promise for enhancing the integration of SNF as a functional phenotypic trait into breeding programs, aiming to enhance SNF efficiency by identifying breeding materials with high SNF capacities.

Plant phenotyping relevance

根圏内の窒素固定という植物生理形質をPETで可視化・定量するためのガス供給システムを開発し、実験的に適用しており、フェノタイピング手法が研究の中心である。

Code and data availability

The paper reports PET imaging of soybean N2 fixation with 34 supplementary multimedia components, but the data availability statement only says data are in the paper/supplementary materials; no authors' public repository URL, deposit, or code availability is provided. The cited prior work and TRIUMF conference link are

No evidence-backed public reproduction asset is currently recorded.