Fungi weaponize plant defenses to combat bark beetles
Researchers from the Max Planck Institute showed that certain Beauveria bassiana strains can infect and kill bark beetles by detoxifying spruce tree defense chemicals (stilbenes and flavonoids). The fungus converts these compounds into less protective forms through two phases, first removing sugar to form aglycones and then methylating them to methylglucosides, which avoids the plant defenses and enables infection. Gene knockouts of the detoxification pathways reduce virulence, indicating these defenses are bypassable. Other fungi, like Cordyceps militaris, may use similar tricks, suggesting a future in biocontrol where fungi replace some chemical insecticides.
