By Susan Milius
The story of a fungus that keeps plants from withering in hot soil turns out to have been missing a character—the virus that makes it all work.
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The fungus Curvularia protuberata grows inside plant tissues without damaging them. In 2002, researchers working in Yellowstone National Park reported that grass colonized by the fungus thrived in soils that simmer at over 40°C (104°F) all summer.