Feeding the 9 billion people we'll have by 2050 could be harder than first thought if the conclusions of a report released last week come true. Researchers at the University of Nebraska-Lincoln note that yield gains are in fact decreasing, which will make meeting global food demands harder. The researchers also report yield plateaus or actual decreases in key crops could be a significant challenge.
The researcher team - which reported its findings in Nature Communications last week - says about 30% of major global cereal crops - rice, wheat and corn - may have hit their maximum possible yields in farmers' fields. The team - which includes Kenneth Cassman and Patricio Grassini of the agronomy and horticulture department, and Kent Eskridge, statistics - studied past yield trends in countries with greatest cereal production and they offer evidence against projected linear crop yield increases.
According to a release announcing the research, the data suggest that the rate of yield gain has recently decreased or stopped for one or more of the major cereal crops in many of the most intensively cropped areas of the world - including eastern Asia, Europe and the United States.
Some are claiming this is a challenge for commercial agriculture, which contends it can meet future food needs. But the stats presented by the UNL researchers offer some insight into the true challenge ahead.
The Institute of Agriculture and Natural Resources scientists calculate that this decrease or stagnation in yield gain affects 33% of major rice-producing countries and 27% of major wheat producing countries. They note that in China the increase in crop yields in wheat has remained constant, and rate of corn yield increase has fallen by 64% for the 2010-2011 period relative to years 2002 to 2003, despite a major increase in ag research spending.
The researchers point to a popular idea that corn yields can rise to 300 bushels per acre - on average - by 2030 - but point out to achieve that goal, producers would have to push yields up 3.6% per year annually to achieve that goal. "This rate is four times greater than the rate of increase in US [corn] yield from 1965 to 2011," the report says.
This new research will add new information to the debate over global food production and the ability to meet rising demand.