Case Studies

Wheat not so welcome in a warming world

Wheat varieties may decrease yield to compensate for a warming climate, according to a study.

Climate change is projected to decrease crop yields in many regions.

To model the effect of rising global temperatures on United States wheat yields, Jesse Tack and colleagues combined results from field trials of wheat varieties in Kansas between 1985 and 2013 with weather data from the site of each field trial.

The authors found that extreme heat in spring and freezing temperatures in the fall were the main drivers of wheat yield loss.

Although global warming will likely reduce wheat’s exposure to freezing temperatures, the authors found that wheat varieties may trade off yield for heat resistance, and that the overall effect of warming on wheat is likely to decrease yield.

Recent wheat varieties exhibited less heat resistance than varieties from previous years.

Rather than calculating temperature exposure from average daily temperatures, the authors calculated exposure from the range of temperatures present each day, and found that the method greatly increased the predictive performance of the wheat yield and temperature effect model.

The results suggest that maintaining sustainable agriculture in a warming world will likely require design of wheat crops with both high yield and high heat resistance, according to the authors.

Source: Mississippi State University