If you say green transition, most people think of the climate goal of reducing CO2 emissions with 70% by 2030. But even though greenhouse gases are the big topic of conversation, the green transition contains many more issues and goals. For example, Denmark and the EU have an ambition that the organic area should increase to 25% of the cultivated area, while the pesticide load should be reduced by 50% by 2030. According to Mogens Støvring Hovmøller, professor of plant pathology at the Department of Agroecology at Aarhus University, it is important in this connection with a greater focus on the role of plant breeding in the green transition. Plant breeding is the key to the development of varieties with a stable high yield as well as resistance to the most important plant diseases in important crops such as wheat.

With two other research groups at Aarhus University's center in Flakkebjerg, Mogens Støvring Hovmøller has received a grant of more than DKK 11 million for a new project, which focuses on plant health, breeding and green transition.

“There is a tendency for plant breeding to be overlooked in the green transition debate. The focus of politicians and the press is, quite naturally, on the goal of a 70% reduction in CO2. Therefore, it is also extra gratifying that the Independent Research Fund Denmark has given us this grant, so we can seek new opportunities to improve disease resistance in wheat, which is perhaps the most important crop in the global food supply,” says Mogens Støvring Hovmøller.

Contemplate the pathogen and the environment in breeding

The project group includes researchers from three different research sections at Aarhus University and Nordic Seed A/S, which is a private plant breeding company with strong research traditions within plant breeding and disease resistance.

“Some of the challenges we face are that declining disease resistance in plants as the pathogens (the diseases) adapt. The more widespread a variety is in cultivation, and the greater the infection pressure in general, the greater the risk that the pathogens will adapt. Therefore, diversity for disease resistance is very important in relation to preventing disease infestation in the crops we grow,” explains Mogens Støvring Hovmøller.

“Research has shown that the effect of disease resistance in plants can be strongly influenced by the environment, for example the temperature. Therefore, you have to combine both pathogen and environment when you develop the crops of the future with effective disease resistance,” explains assistant professor Chris Sørensen from the Department of Agroecology, who helped formulate the research project.

Brand new research area

The development of new pathogenic disease breeds has traditionally been the cause of the plants' lost resistance, and there is a constant need to find new resistance, among other things, to rust fungi. However, rust fungi, which often attack wheat, have been shown to attack crops more frequently with milder winters due to climate change, while recent research from AU has shown that cold can make wheat plants that are otherwise susceptible resistant to severe yellow rust disease.

“We have found that rust-susceptible varieties of winter wheat can develop resistance after a cold period. The phenomenon is called cold-induced resistance and our studies are the first to show a strong effect against yellow rust,” says Chris Sørensen.

And that is exactly what the researchers now have funds to investigate. Varieties with cold-induced resistance to another fungus, pink snow mold, have previously been bred, but cold-induced resistance to rust has not previously been studied or utilized in winter crops, just as the rust fungus' ability to adapt to such resistance has not previously been studied.

The project, entitled "Temperature induced disease resistance", will support the green transition by examining the following:

1. genetic basis for temperature-induced resistance to rust in winter wheat
2. development of genetic markers for the targeted exploitation of this form of resistance in plant breeding
3. risk of adaptation as well as durability of temperature-induced rust resistance in wheat

The project focuses on three different rust diseases: yellow rust, brown rust, and black rust. And the project group has very good conditions for work, as the Department of Agroecology in Flakkebjerg houses the "Global Rust Center", which serves as a global hub for research in rust diseases.

Crucial for sustainable green transition of agriculture

The new project is therefore focused on one of the lesser known, but no less important, sides of the green transition. And the results from the project are expected to play a major role in the green transition in particular in relation to Denmark's and the EU's goal reducing the use of pesticides with 50%, as well as increasing the organic cultivation area.

“It is quite imperative that we think about plant breeding in this context. That is why this project is so important, and we are pleased that the Independent Research Fund Denmark has chosen to support our project. I think that very few people realize what a huge task we are facing with the green transition. We may have to double or triple the organic area across Europe in just a few years, and at the same time the pesticide load on the conventional area must be significantly reduced. So, we need this and similar projects, where we by using plant breeding can develop new varieties that have better and more durable resistance to both known and new diseases, which we for sure will need to fight in a world with more extreme weather and climate,” says Mogens Støvring Hovmøller.