To learn the art of sustainable, pathogen-free farming, one group of researchers has turned its attention to the ambrosia beetles, a species of tree-dwelling beetle that has been cultivating fungi for 40 million years.

Ambrosia beetles live in colonies inside trees. When beetles set out to colonize new trees, they carry fungal spores with them. Upon arrival they plot a new fungal farm and wait to harvest the fruits of their labor.

Like humans, the beetle farmers must protect their crop against harmful pathogens and maintain an environment conducive to the fungus' health.

Over the last year-and-a-half, researchers with the European Union-funded Farming In Beetles project have been studying ambrosia beetles to better understand their sustainable farming strategies.

"My ultimate goal in this project has been to identify possible solutions that can be taken up by scientists and researchers in forestry and agriculture," project coordinator Peter Biedermann, a researcher with the Max Planck Institute for Chemical Ecology, said in a news release. "Just like in the beetle nests I am studying, fungal pathogens pose a huge threat to human agriculture, so understanding the beetles' success might provide insights that are relevant for our agriculture as well."

Initial observations suggest ambrosia beetles plant different fungus varieties in a specific order, similar to crop rotation strategies employed by human farmers. They also utilize bacteria to promote the growth of their fungal crops and to combat pathogens.

"It was also really surprising to find out that in the fruit-tree pinhole borer, the ambrosia beetle species that I mainly study, the major fungus crop consists of a single strain that can be found across the whole of Europe," said Biedermann. "Humans also grow a few very successful cultivars of their crops."

Biedermann and his colleagues are now focused on figuring out how various chemical compounds and bacteria are deployed and manipulated by the beetles to foster a healthy growing environment.

Researchers believe insights uncovered by the project could be translated for use by human farmers.

"It would be very interesting if we could apply bacteria to our crops in order to produce antibiotics against crop pests," Biedermann said. "This is exactly what the farming beetles seem to do."