What is in this article?:
• In some parts of the world, water is in short supply, but farmers often devote what they can to rice farming, because the crop is so important.
• However, research has led to a simple but profound solution that requires less water — growing rice in fields, a practice called aerobic rice production.
IN THIS UNDATED file photo, rice plants grow in a field in Hyderabad, India, as part of a University of Florida study. Though little-known in the West, field-grown rice, also known as aerobic rice, is gaining popularity in the Eastern Hemisphere and is often rotated with other grain crops. A new study from UF’s Institute of Food and Agricultural Sciences shows that corn plants grown after aerobic rice yield about 5 percent more grain than corn grown after paddied rice, a process requiring more elaborate soil preparation.
Can be lifesaver
But in a drought there may not be enough water to keep rice paddies flooded. Under those circumstances, aerobic production can ensure that a community has rice to eat, while the paddied plants wither away.
“The real impact of aerobic rice will be shown in a rainfall shortage year,” Mylavarapu said. “However, in a rainfall shortage year, we have to be able to provide supplemental irrigation to aerobic rice and keep the root zone moist. So if there’s a very bad drought, even aerobic rice will fail.”
He adds that few rice varieties have been developed specifically for aerobic production. In time, breeders may develop improved varieties and close the “yield gap” with paddied rice.
Currently, Mylavarapu’s focus is on another aspect of the cropping system — overall grain production in systems where rice is rotated with corn. This approach is used on about 8.65 million acres in Asia because little soil preparation is needed to plant corn in a field following aerobic rice. In contrast, rice paddies must be drained and converted from a flooded anaerobic system to an aerobic system before the land can be used for corn.
In the study, researchers found that corn yields were about 5 percent higher when the corn followed aerobic rice, compared with paddied rice.
So far, aerobic rice production hasn’t caught on with U.S. farmers, but that could be just a matter of time, he said.
“In the U.S., water quality is usually a bigger issue than water quantity,” Mylavarapu said. “Certainly, it (aerobic rice) will become a very important factor for the U.S. to consider in the future, with climate change.”
The United States is the world’s 10th largest producer of paddied rice, with annual production of about 12 million tons, according to the United Nations’ Food and Agriculture Organization. Arkansas is the leading U.S. rice producer; Florida ranks seventh.
The study was funded by the U.S.-India Agricultural Knowledge Initiative through the U.S. Department of Agriculture. The research team included Mylavarapu, UF colleagues Dakshina Kadiyala and Yuncong Li; Gudigopuram Reddy of North Carolina A&T State University and M.D. Reddy of Acharya N.G. Ranga Agricultural University in Hyderabad, India.