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bioRxiv · 10.1101/2025.03.04.641427

Adaptation of Plasmid-ID Technology for Evaluation of N2-Fixing Effectiveness and Competitiveness for Root Nodulation in the Sinorhizobium-Medicago System

Schumacher, J.·Dusek, N.·Mendoza-Suarez, M.·Geddes, B. A.
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Abstract

Maximizing the nitrogen fixation occurring in rhizobia-legume associations represents an opportunity to sustainably reduce nitrogen fertilizer inputs in agriculture. High-throughput measurement of symbiotic traits has the potential to accelerate the identification of elite rhizobium/legume associations and enable novel research approaches. Plasmid-ID technology, recently deployed in Rhizobium leguminosarum, facilitates the concurrent assessment of rhizobium nitrogen-fixing effectiveness and competitiveness for root nodulation. This study adapts Plasmid-ID technology to function in Sinorhizobium species that are central models for studying rhizobium-legume associations and form economically important symbioses with alfalfa. New Sino-Plasmid-IDs were developed and tested for stability and their ability to measure competitiveness for root nodulation and nitrogen-fixing effectiveness. Rhizobial competitiveness is measured by identifying strain-specific nucleotide barcodes using Next-Generation Sequencing while effectiveness is measured by GFP fluorescence driven by the synthetic nifH promoter. Sino-Plasmid-IDs allow researchers to efficiently study competitiveness and effectiveness in a multitude of Sinorhizobium strains simultaneously.

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Schumacher, J., Dusek, N., Mendoza-Suarez, M., Geddes, B. A.. 2025-03-04. Adaptation of Plasmid-ID Technology for Evaluation of N2-Fixing Effectiveness and Competitiveness for Root Nodulation in the Sinorhizobium-Medicago System. https://doi.org/10.1101/2025.03.04.641427

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