Better crops using evolved bacteria

Bioteknologi og biokemi

Newly appointed professor at DTU Bioengineering develops new strains of soil bacteria that can enhance the growth of plants and strengthen their resistance.

The bacterium Bacillus subtilis is known to have a positive effect both on plants and on human intestinal flora. Newly appointed professor at DTU, Ákos Kovács from DTU Bioengineering, sees a big future for this little bacterium. In his inaugural lecture, he presents the latest knowledge of how Bacilli interact within a biofilm and with a fungus, and how improved strains of Bacilli provide a bright future for plant growth improvement and to strengthen plant resistance against fungal attacks. 

Bacillus subtilis is one of the species we examine, but we also explore other similar Bacilli. In a way, we mainly concentrate on species, that are benefitting our life, that can be used for plant protection or has a probiotic effect on humans as well,” says Ákos Kovács.

The newly appointed professor explains, that Bacillus subtilis and other closely related species are used to promote plant growth, because it grows on a plant root, the developped biofilm covers it, and it additionally produces various anti-fungal compounds, that can keep away other organisms. At the same time B. subtilis also mobilizes phosphate, so seeds can germinate faster, plants can grow more efficiently and these results in growth-improvement. Furthermore, it triggers the defensive system of the plants against pathogens. All in all, these plant growth-promoting microorganisms have important beneficial impact on crop yield.

“Our focus is to exploit these beneficial effects. We can improve these properties by understanding, what is really needed for the plant biocontrol properties. We can also evolve laboratory strains under selected conditions, for example in the presence of a plant or together with a fungal species, and see how they will adapt to that certain condition. After several weeks, we can see how they grow in the presence of different fungi, and how they inhibit fungi, allowing us to potentially obtain bacterial strains with beneficial effect against plant-pathogens and so on,” says Ákos Kovács.

The aim of our research is not to create genetically modified organisms, GMOs, but to obtain strains just by evolving them and adjusting to certain conditions, also called adaptive evolution. Ákos Kovács explains, that their approach will provide a new way for strain improvement, and more and more people are using these methods to improve biocontrol strain performance and their beneficial effects, since GMO in an European context is still controversial and not accepted.   

“Companies can select their own microorganisms and strains from their collection– if they have the best organisms for that process. They always try to optimize certain properties of their production strains, including plant growth promotion. One way is to use adaptive evolution, that provides an innovative addition for strain development and product improvement.”

The long-term goal of Ákos Kovács’ research is to apply their insights towards Bacilli-based plant protection and human probiotics via companies.

“DTU provides good opportunities, if you want to apply these evolutionary tools and techniques. I´m interested in using basic science to understand processes, but I´m also interested in using this knowledge towards applications. I do think that DTU offers a good background to do basic research and to use this basic knowledge towards applications. That is unique in this sense at DTU. Additionally, DTU Bioengineering hosts superb groups with whom we aim to collaborate on scrutinizing secondary metabolites and researching fungi to reveal the impact of our evolved bacterial strains” says Ákos Kovács.

See the website for Ákos Kovács' research group Bacterial Interactions and Evolution