Highly variable precipitation is causing headaches for farmers across the Midwest, as they contend with the effects of climate change. To bolster crop yields, more farmers in Indiana and elsewhere are turning to irrigation to offset hot, dry periods. This practice, however, may undermine a natural drought-tolerance strategy that is less costly and doesn’t draw upon limited freshwater resources: soil microbes that help plants survive drought.
IU researchers are leading a unique collaboration between social scientists and biologists to study farmer decision making and the presence of soil microbes that help plants tolerate drought. The work is funded by a grant from the National Science Foundation.
Some soil microbes have been found to have a protective effect on crops in drought conditions. In greenhouse experiments, the naturally occurring microbes from some soils have been shown to improve yields under drought conditions.
To determine whether farm management can nurture soil microbes that aid crop drought tolerance, social scientists first interviewed 90 farmers in Indiana, Illinois, and Michigan about practices they employ on their fields. The survey included questions on irrigation, crop rotation, fertilizer application, and more.
Then, biologists took soil samples fromto test for the presence of certain microbes and key microbial traits, such as the ability to form biofilm. Additional experiments tested the effects of soil microbes on crop yields under drought. The combination of interview data, soil data, and plant data is helping to pinpoint factors that encourage microbial communities in soil to protect plants from drought.
Currently, researchers are working to determine why microbial communities from some farmlands seem to protect plants from drought, while others do not. The results will be shared with participating farmers, who can use the data to determine which strategies might best increase crop resilience on their farms.
In 2026, researchers will return to each participant to repeat the study, seeking to discover if or how farmers changed their management practices in between interviews. Researchers will also take soil samples again to see if these practices affected the microbes in the soil.
Updated Nov. 16, 2022
