By Susan Milius
Southern pine beetles get by with a little help from their friends, including a newly discovered bacterium that makes a weed killer.
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When the beetles burrow into trees to lay eggs, they leave behind spores that sprout into a garden of fungal baby food. Now electron microscopy, beetle sampling and lab tests suggest that the female beetles also mix in helpful strains of bacteria, says Jarrod Scott of the University of Wisconsin–Madison.
The bacteria secrete a previously unknown small molecule that discourages weedy fungi from crowding out the garden, Scott and his colleagues report in the Oct. 3 Science.