Agriculture in Europe is increasingly affected by extreme weather conditions that lead to crop losses. In 2018, the damage in Germany alone amounted to around 770 million euros. Making wheat plants more resilient to these stresses could make a significant contribution to safeguarding global food production.
As part of the VolCorn project, scientists from four non-university research institutions have been studying, from very different perspectives, how wheat plants and the microorganisms such as fungi and bacteria that colonize them respond to stress factors caused by extreme weather conditions such as drought, flooding or pests.
The underlying assumption is that the microbiota, the community of microorganisms in and around the plant, is as important to the plant as microorganisms are to the human immune system. A better understanding of these interactions is therefore central to better preparing plants for these stress situations.
Volatile organic compounds (VOCs), which are produced by the plant and also used to "communicate" with the microbiota, play a key role in the plant's defense against these stressors. The researchers have used modern approaches to unravel these complex relationships. They used systems biology methods to study changes in plant metabolism and, at the same time, changes in the microbiota.
Microorganisms can help with climate stress
The research shows that floods and droughts not only generally reduce the growth and yield of wheat, but also change the microbiota in the roots and leaves. In particular, more pathogenic microbes colonize the early growth stages. As a result, stressed plants become more susceptible to disease.
To the researchers' surprise, however, beneficial bacteria also accumulate in the root zone during flooding, promoting the uptake of nutrients and vitamins by the plant. At the same time, the plant itself massively changes its metabolism.