Ug99 is a virulent strain of black stem rust fungus that attacks wheat plants - a crop that feeds more people than any other food source on Earth. Since the Green Revolution of the 1960s, farmers have been successfully growing disease-resistant wheat varieties. But Ug99 has evolved. There are now precious few wheat crops anywhere that are resistant to it. The blight has already crossed from Africa into Asia and there are fears it will spread further into regions where a billion people depend on wheat for their survival.
A warming climate has improved the birds' Siberian nesting site, leading to plagues of the birds invading the Washington state town of Stanwood.
Pollution far below the level seen as dangerous for aquatic life has nevertheless dramatically altered animal behaviour in North American lakes.
Mushrooms in England are starting to pop up earlier and staying around later than they used to, according to 55 years of amateur naturalists' records.
Drug-Resistant Flu Detected: Japanese strains appear transmissibleFor the first time, researchers report drug resistance in type B influenza virus and say the drug-resistant strain may jump from person to person.
No Escape: There's global warming on Mars tooThe overall darkening of Mars' surface in recent decades has significantly raised the Red Planet's temperature, a possible cause for the substantial, recent shrinkage of the planet's southern ice cap.
Kill-save gene combo might fight malariaA technique that might someday enlist mosquitoes in the fight against malaria has passed an early test.
Freeze-thaw cycles: How not to mix soilThe repeated cycles of ground freezing and thawing that occur in many places don't do a surprising poor job of churning the soil.