Nutty and fungi-ble taxol sources.

Scouting for chemical clues to the puzzle of why eastern filbert blight hits some hazelnut cultivars harder than others, Angela M. Hoffman and her colleagues at the University of Portland in Oregon made a startling discovery. The most resistant trees are making paclitaxel, the active ingredient in the anticancer drug taxol. The trees also produce a host of related taxanes that chemists can convert into the pharmaceutical.

Pacific yew had been the only source of paclitaxel, a costly drug ingredient that's in high demand. Hoffman's team has found taxanes in all parts of the blight-resistant hazelnut trees, but concentrations are only one-tenth as high as in the yew trees. However, the hazelnut taxanes represent a double whammy. Inside tissues of the apparently healthy trees, Hoffman discovered independent producers of paclitaxel--various unidentified fungi. Her group is now investigating what role, if any, the taxanes play in protecting hazelnuts from disease.