Food shortage may hit world by 2050

Improved agronomic traits responsible for the remarkable increases in yield have reached their ceiling for some of the world’s most important crops.

Don Ort, the Illinois professor of crop sciences and scientist, said: “Global change is happening so quickly that its impact on agriculture is taking the world by surprise. Until recently, we haven’t understood the urgency of addressing global change in agriculture.”
The need for new technologies to conduct global change research on crops in an open-field environment is holding the commercial sector back from studying issues such as maximising the elevated carbon dioxide advantage or studying the effects of ozone pollution on crops.

However, U of I’s Free Air Concentration Enrichment (FACE) research facility, Soyface, is allowing researchers to conduct novel studies using this technology capable of creating environments of the future in an open-field setting.

Open-field experiment
Ort said: “If you want to study how global change affects crop production, you need to get out of the greenhouse. At Soyface we can grow and study crops in an open-field environment where carbon dioxide and ozone levels can be raised to mimic future atmospheric conditions without disturbing other interactions.”

From an agricultural standpoint, one of the few positive aspects of global change has been the notion that elevated carbon dioxide in the atmosphere will stimulate photosynthesis and result in increased crop yields.

But recent studies show that crops grown in open fields under elevated carbon dioxide levels resulted in only half the yield increase expected and half of what the United Nation’s Intergovernmental Panel on Climate Change used in their model predictions regarding the world’s food supply in 2050.

Ort said: “Elevated carbon dioxide is creating a global warming effect that in turn is driving other climate change factors such as precipitation patterns. By 2050, rainfall during the Midwest growing season is projected to drop 30 per cent.”

U of I researchers are also studying how elevated ozone levels will affect crop yields.
Soybean plants are being evaluated in elevated ozone at Soyface. New studies show that yields in the tri-state area of Indiana, Illinois and Iowa have been suppressed by 15 per cent due to ozone pollution. Ort said if the same cultivars of soybean are used in 2050 that are being planted now, producers can expect to see an additional 20 per cent drop in yield due to expected increases in ozone levels by the middle of the century.
Ort said: “Ozone is a secondary pollutant caused by the interaction of sunlight with pollution clouds produced in industrialised areas and carried over rural areas by wind. For example, if pollution from Chicago blows out of the city into agricultural areas, it can interact with sunlight to produce ozone and cause plant yields to suffer.”

Because ozone is an unstable gas, its concentration levels vary greatly, Ort said. Thus, agricultural areas located near industrial areas will face the greatest challenges.

Ort said: “The Soyface experiment and historical data recorded over the past 10 years both indicate that for every additional one part per billion of ozone, soybean yields will decrease 1.5 bushels per acre. We are applying for funding to examine corn’s sensitivity to ozone at Soyface, but a historical analysis indicates a significant sensitivity and yield loss.”

In addition to generating results about the response of crops to global change, the report has provided proof of concept that adaptation of crop plants to global change can be achieved in the field. Ort believes that this approach can and needs to be scaled to much larger sizes necessary for conventional selective breeding.