Identification of rhizobia bacteria associated with narrow-leaved lupin in Swedish organic agriculture
Project overview
Participants
More related research
Short summary
In this project, we investigate the survival and adaptation of rhizobia introduced in Sweden when growing narrow-leaved lupin over recent years, to see if they are better adapted to Sweden’s growing conditions.
Firstly, we determine the survival of rhizobia from different farms across Sweden, comparing organic to non-organic farms. Then we isolate and identify the rhizobia present in the soil, to see if they have evolved to new strains. Lastly, we test how well they perform in different climatic conditions, focussing on capturing nitrogen form the atmosphere.
This findings of this project can be used to guide farmers in their inocula application when sowing new crops and can contribute to the promotion of organically grown legumes, which in turn promote sustainable cropping systems.
Background
Legumes play an important role in sustainable agriculture through their association with specific beneficial soil bacteria: rhizobia. These bacteria can take up nitrogen from the atmosphere and make it available for plants. This relationship means that nitrogen fertilisers are not needed, and for this reason legumes play a key role in organic agriculture.
However, one challenge is that the relationship is specific: not all legume species can interact with all soil rhizobia. When a new legume crop is introduced, e.g. narrow-leaved lupin, a promising crop for Nordic climates; the right bacteria are not there.
To overcome this issue, formulations or inocula have been developed containing living rhizobia for specific plant species. The bacteria can survive in the soil for several years, interacting with native soil bacterial communities, including native rhizobia, and adapt to the new climatic conditions.
Organically managed soils have a higher diversity in their microbial communities, which could result in a higher rate of survival or adaptation, meaning that farmers do not need to re-apply new inocula in following years.
Project leader: Martin Weih
Scientific coordinator: Fede Berckx
Project participants: Jonathan Cope, Iris Dahlin