<i>Interstellar</i>-like blight could ravage Earth’s wheat

Paramount/Warner Brothers/The Kobal Collection

Interstellar-like blight could ravage Earth's wheat

In the 2014 sci-fi movie Interstellar (pictured above), a cataclysmic blight has wiped out the world’s wheat, forcing astronauts to hunt for another habitable planet. A new study on barley yellow dwarf virus (BYDV), a wheat and cereal crop disease, shows that this fictional dystopia carries more than a few grains of truth. Researchers made this discovery by relying on a basic prediction for climate change. At our current pace, global atmospheric levels of carbon dioxide (CO2) are expected to rise 60% by the end of the century (400 μmol/mol versus 650 μmol/mol). So the scientists split 96 wheat seeds between two greenhouses and grew the sprouts with current or future CO2 levels. After 10 days, the team exposed one leaf from half the plants to aphids infected with BYDV. The tiny insects are the main mode of transport for BYDV, which occurs sporadically across the globe but can cause major damage to cereal crops. One month later, the young plants were harvested and examined for virus and damage. Higher carbon dioxide boosted the reproduction of barley yellow dwarf virus in wheat crops by 37%, the team reports online this month in Global Change Biology—the first time the gas has been shown to spur a plant virus. Plants grow larger with greater access to CO2, so one might argue that virus levels increased because the germs had more tissue to feast on. That wasn’t the case here. Carbon dioxide exposure marginally elevated the size and weight of the young plants, but the extra growth didn’t correlate with viral production. Heftier viral infections mean a wider range of spread, the team reports, suggesting a future where wheat faces more severe attacks from BYDV. They’re conducting ongoing research on the possible outcomes with adult plants and crop yields.