Overseeing the rhizobial inoculant industry

Legumes form a symbiotic association with a group of soil bacteria called rhizobia. The rhizobia form nodules on legume roots and fix atmospheric nitrogen into plant-available nitrogen. In farming systems, this biological nitrogen fixation reduces reliance on industrially synthesised fertilisers. The use of rhizobia as an inoculant on legume crops saves the agricultural industry approximately $3.5 billion each year in applied nitrogen costs.

Since the 1950s, through extensive research by Australian universities, CSIRO and state agencies, elite strains of rhizobia have been selected as commercial inoculants. These inoculants are effective at nodulating and fixing nitrogen on target legume species. Recommended inoculants are mass-produced in peat, freeze-dried, granular or liquid form by commercial inoculant companies, purchased by the grower, then applied to the soil or legume seed just prior to sowing. This farming practice introduces large numbers of nitrogen-fixing rhizobia in close proximity to the emerging legume root and enhances the opportunity for the rhizobia to nodulate and fix nitrogen with the plant.

The Committee

The National Rhizobium Steering Committee (NRSC) is comprised of highly experienced rhizobial scientists from all over Australia. The role of the NRSC is to ensure the quality of commercial rhizobial inoculant strains is maintained for the benefit of Australian growers by providing oversight and knowledge to the industry. The NRSC assess, endorse and monitor the rhizobial strains and carriers (formulations) that are manufactured by the inoculant industry for sale and use by Australian farmers.


The NRSC aims to protect the industry against strains that don’t have effective science supporting their use while protecting farmers from using poor quality inoculants. The NRSC also ensures science connects with industry needs through strong and vigorous relationships with commercial inoculant manufacturers.

The NRSC achieves this by holding bi-annual Committee meetings to assess the efficacy of the current rhizobial inoculant strains and discuss updated scientific findings relevant to the industry. The NRSC works closely with the Grains Research Development Corporation (GRDC) and hosts annual workshops and discussion panels with Australian commercial inoculant manufacturers.

For further information on the NRSC or its members, contact Dr Graham O’Hara.

NRSC members


Dr Graham O’Hara
Legume Rhizobium Sciences (LRS) and Murdoch University
Perth, Western Australia

Executive Officer

Helen Shortland-Jones
LRS and Murdoch University
Perth, Western Australia


Dr Ron Yates
Legume Rhizobium Sciences (LRS), Department of Primary Industries and Regional Development (DPIRD) and Murdoch University
Perth, Western Australia

Dr David Herridge
University of New England
Armidale, New South Wales

Dr Tony Vancov
Australian Inoculants Research Group (AIRG)
NSW Department of Primary Industries (DPI)

Menangle, NSW

Ashlea Webster
Australian Inoculants Research Group (AIRG)
NSW Department of Primary Industries (DPI)
Menangle, NSW

Dr Rosalind Deaker
University of Sydney
Sydney, New South Wales

Dr Liz Farquharson
Department of Primary Industries and Regions South Australia (PIRSA) – South Australian Research and Development Institute (SARDI)
Adelaide, South Australia

Dr Matthew Denton
University of Adelaide
Adelaide, South Australia

Useful links

Inoculating Legumes: Practice and Science

This handbook was written collaboratively by a group of Australian experts in the field of rhizobiology and nitrogen fixation from universities and state departments. The target audience includes growers, grower groups, commercial and government advisers, agribusiness, research agronomists, legume breeders, seed pelleters, resellers and seed merchants. Users of the handbook should gain increased knowledge of legumes and legume nodulation in farming systems and benefit from more effective inoculation practice on their farm leading to higher farm productivity through enhanced legume nitrogen fixation and system nitrogen supply.

Learn more about inoculating legumes

Australian Inoculants Research Group (AIRG)

AIRG controls and maintains the quality of legume inoculants through collaboration with industry, universities and Research and Development (R&D) bodies.

Learn more about AIRG

Pasture Legumes in Southern Australia Management Guide

This guide shares knowledge to support the management of new annual legume pasture species domesticated, bred and selected to suit southern Australia. These 'second generation hard-seeded legumes' include different species of clover, serradella, biserrula and trigonella - they are useful where subclover or medics do not perform well. The guide covers species choice, soil requirements, nursery paddocks, establishment, maximising nitrogen fixation, rotation options, harvesting and livestock production.

Learn more about pasture legumes

Strain Change for Inoculant Groups E and F

Two improved inoculant strains have been selected to facilitate successful establishment and production of field pea, lentil and vetch (Group E) and faba bean (Group F) on acidic soils, commencing in the 2024 growing season. The data supporting this change has been extensively reviewed and endorsed by the NRSC.