Comparative genomic analysis of Bradyrhizobium strains with natural variability: efficiency and competitiveness implications

A major challenge facing farmers is obtaining the nitrogen needed to support plant growth. Inoculation of legume crops with rhizobia, which supply plants with the required nitrogen, is a green alternative to environmentally hazardous nitrogen-fertilizers. However, rhizobia vary in their effectiveness, and the success of inoculants depends on their ability to outcompete native and poorly-effective rhizobia. Thus, development of highly-competitive and highly-efficient rhizobium inoculants is a key challenge to ensuring rhizobium inoculation becomes a cornerstone of sustainable intensification of agriculture. Here, we will use genomic approaches to characterize the genomes of 12 natural variants of the soybean symbiont, Bradyrhizobium japonicum. Despite these 12 organisms being closely related, their symbiotic properties vary. We will assemble and compare the genomes of the 12 strains, looking for genetic variations such as gene gain, gene loss, and nucleotide substitutions. Results will allow us to identify the genetic basis for the phenotypic differences, laying the groundwork for future work engineering elite Bradyrhizobium inoculants.

Faculty Supervisor:

George diCenzo

Student:

Partner:

Universidade Estadual de Londrina

Discipline:

Life Sciences

Sector:

Green/Alternative Energy; Biotechnology; Agriculture and Food

University:

Queen's University

Program: