10. July 2024
New bacterium described:
Hope in the fight against ash dieback
In a study recently published in the journal "Systematic and Applied Microbiology", researchers from the Leibniz Centre for Agricultural Landscape Research (ZALF) report on the isolation and investigation of a bacterium that could be an effective means of combating ash dieback. Since the early 1990s, ash trees have been severely affected by a fungus that causes the death of branches and shoots. Despite intensive efforts, no effective control measures have yet been found.
The research group of Dr. Andreas Ulrich at ZALF has isolated a bacterial strain from the leaves of healthy ash trees, analyzed it genetically and described it as a new bacterial genus. In an experiment, they were able to show that these bacteria, called
Schauerella fraxinea, are able to inhibit the growth of the fungus
Hymenoscyphus fraxineus, which causes ash dieback. Using genome analysis, the researchers also found genes involved in the production of substances that inhibit fungal growth.
Ash trees (Fraxinus excelsior) are deciduous trees native in large parts of Europe. Their wood is often used for furniture, parquet flooring or musical instruments because of its good properties. Ash dieback was first detected in Europe in the early 1990s and has since spread rapidly. The disease causes branches and top shoots to die. This weakens the trees and has led to a sharp decline in native ash populations, with both ecological and economic consequences.
Conventional control methods, such as chemical treatments or breeding for resistance, have had little success. Alternative approaches are being sought, including the use of the natural microbiome of uninfected ash trees. The bacterium could play a critical role in controlling this devastating disease. Field studies have shown that
S. fraxinea is more abundant on the leaves of healthy ash trees than on the leaves of infected ash trees. This suggests that the bacterium contributes to the resistance of the trees.
The next step will be to investigate whether the bacterium is able to establish in ash trees over longer period which is a prerequisite for applying it in biological control. To this end, the researchers have developed a method to detect the presence of
S. fraxinea using genetic markers. "Our next steps are to understand the mechanisms by which Schauerella fraxinea protects ash trees against ash dieback. To this end, we are planning further laboratory and field studies to investigate the interactions between the bacterium and the fungus," says Dr. Andreas Ulrich. The research team will also investigate how the bacterium can be used in practice.
By utilizing the natural microbiome of healthy ash trees, this approach offers hope for the conservation of this important forest species and its ecosystems. The bacterium could make a significant contribution to further research to combat ash dieback.
Funding reference
This research was funded by the Forest Climate Fund (WKF) of the German Federal Ministry of Food and Agriculture (BMEL) and the German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUV), administered by the Agency for Renewable Resources (FNR), funding reference 2219WK22I4.
Further information:
Note on the text: This is a summary of the original text created with the help of artificial intelligence:
Behrendt, U., Burghard, V., Wende, S., Ulrich, K., Wolf, J., Neumann-Schaal, M., Ulrich, A. (2024) Schauerella fraxinea gen. nov., sp. nov., a bacterial species that colonises ash trees tolerant to dieback caused by Hymenoscyphus fraxineus. Systematic and Applied Microbiology 47, 4, Article 126516, veröffentlicht unter der Lizenz CC BY 4.0 https://creativecommons.org/licenses/by/4.0/.
The text has been carefully reviewed and edited by ZALF according to the AI guidelines.
