Rhizobia are soil bacteria that fix nitrogen into plants and soils through their symbiosis within legume root nodules. Rhizobia compatible with our exotic crop and pasture legumes aren’t naturally present in Australian soils. So, many highly effective nitrogen-fixing bacteria have been sourced from other parts of the world and introduced as commercial inoculant strains.
However, it has become increasingly clear that the genetic diversity of strains nodulating legumes far exceeds the diversity of strains introduced as inoculants. This could partly be explained by horizontal transfer of symbiosis genes between inoculants and pre-existing soil bacteria, creating new and not always effective hybrid rhizobia. It could also be due to the accumulation of mutations giving rise to newly evolved rhizobia.
In both cases, these novel symbionts can outcompete inoculants to nodulate target legumes, reducing the benefits of legume inoculation to growers. However, we lack the genomic data on the more than 40 commercial legume inoculants needed to develop management strategies to combat suboptimal effectiveness. In this project, we have developed an in-house complete genome sequencing, assembly, annotation, and polishing pipeline to provide these critical baseline data and are using this resource to answer questions of rhizobial evolution and function.
About the Speaker
Dr Maclean Kohlmeier completed his PhD in Microbiology in 2020 at the University of Manitoba in Winnipeg, Manitoba, Canada, where he developed an interest in bacterial metabolism and symbiosis in root nodule bacteria. He pursued this interest with the Legume Rhizobium Sciences group at Murdoch University, where he was offered a Postdoctoral researcher position. He utilises genetic strategies as well as whole genome sequencing techniques to uncover the intricacies of metabolism, symbiosis, and gene transfer the rhizobia.
3:30 - 4:15pm: Seminar
4:15 - 4:30pm: Q & A
This event will be followed by networking drinks and nibbles hosted by SoilsWest.
More Soil Seminars
This event is part of a series of free soil seminars, held at Murdoch on the first Monday of every month. Other speakers include:
- Monday 04 April - Dr Richard Bell (Murdoch), Dr Francesca Brailsford (Murdoch)
- Monday 02 May - Dr Yvette Hill (Murdoch)
- Monday 06 June - Ed Barret-Lennard (DPIRD), Rushna Munir (DPIRD)
To find out more about these events, please visit the SoilsWest website or email firstname.lastname@example.org.
SoilsWest is a research alliance between academia, government and industry for a more integrated approach to soil research. You can find out more by visiting: soilswest.org.au