PhD research student

Project: Development and optimisation of novel inoculants for grain legumes

Agronomic sustainability can be facilitated by incorporating legumes into crop rotations. Symbiotic root-nodule bacteria associated with legumes (collectively known as rhizobia) are able to fix atmospheric nitrogen through the process of biological nitrogen fixation (BNF), and thus reduce the need for synthetic fertiliser input. Furthermore, this symbiosis is also able to improve legume crop establishment and production.

The known yield instability of grain legumes can be caused by poor or inefficient nodulation with soil rhizobia. One way of alleviating inefficient nodulation is by inoculating elite rhizobial strains selected for their nodulation and nitrogen-fixing abilities in the form of inoculants. These agronomical products formulate one or more rhizobial strain with a carrier substance which provides some level of protection and nutrients to the bacteria. Inoculants have a relatively short shelf-life when compared with standard agronomical products thus limiting their use from their production. This is mainly due to the large die-off of cells that occur from the formulation stage mainly due to desiccation stress

Therefore, the main aim of this project is the optimisation of novel legume inoculants for peas and faba beans focusing on the selection of an elite strain that, at the same time, show a high tolerance to desiccation.

The objectives of the project are:

  • Identify a set of naturally desiccation-tolerant elite rhizobia
  • Determine the genetic basis for this stress tolerance through GWAS and population genetics
  • Develop commercial inoculant products with improved storage and field performance

Funding acknowledgements: PhD funded by University of Stirling, The James Hutton Institute, Legume Technology Ltd and Processors and Growers Research Organisation (PGRO).