Data from: Intensifying drought eliminates the expected benefits of elevated carbon dioxide for soybean

Stimulation of C3 crop yield by rising concentrations of atmospheric
carbon dioxide ([CO2]) is widely expected to counteract crop losses that
are due to greater drought this century. But these expectations come from
sparse field trials that have been biased towards mesic growth conditions.
This eight-year study used precipitation manipulation and year-to-year
variation in weather conditions at a unique open-air field facility to
show that the stimulation of soybean yield by elevated [CO2] diminished to
zero as drought intensified. Contrary to the prevalent expectation in the
literature, rising [CO2] did not counteract the effect of strong drought
on photosynthesis and yield because elevated [CO2] interacted with drought
to modify stomatal function and canopy energy balance. This new insight
from field experimentation under hot and dry conditions, which will become
increasingly prevalent in the coming decades, highlights the likelihood of
negative impacts from interacting global change factors on a key global
commodity crop in its primary region of production.