A Dry Subject

CAFNR researchers study the effects of drought by making their own

Droughts have a devastating effect on farms. In Missouri and most of the world, droughts are the leading cause of crop failure. They increase consumer costs, kill livestock, reduce crop yields, and trigger wildfires and dust storms. They also can cause malnutrition and famine, social unrest and political instability.

Researchers in the University of Missouri College of Agriculture, Food and Natural Resources (CAFNR) recently received a $1,558,125 grant to construct drought simulators that enable the scientists to study how reduced water availability affects plants and crop productivity.

The Missouri Life Sciences Research Board grant funds the construction of four mobile rain shelters, which researchers can use to vary the amount of water that test plants receive, simulating everything from short dry spells to persistent and severe drought conditions.

Research on the move

The shelters look like 50-by-100-foot greenhouses on railroad tracks. They move away from test plants when the weather is sunny and cover the plots when rain approaches.

Two shelters will be built at CAFNR’s Bradford Research and Extension Center east of Columbia; the first is scheduled to be completed in late 2009. A third shelter will be built at the Delta Research Center, Portageville, in the southeastern part of Missouri. The fourth shelter will be located at the Horticulture and Agroforestry Research Center, New Franklin.

The locations represent the varied environments, crop species and soil types that are agriculturally important to the state. This strategic placement allows researchers to accommodate any crop, forage and turf species grown in Missouri and surrounding states.

“This project will create a network of drought simulators unlike any other in the U.S., providing Missouri scientists with state-of-the-art field facilities to conduct a broad range of drought-related translational research,” said Felix Fritschi, an assistant professor in CAFNR’s Division of Plant Sciences, who leads the effort. “Our objective is to take laboratory discoveries in basic plant drought research and develop real-world products and practices to improve food security and increase profitability for farmers.”

“Water is a finite resource that is in great demand for a wide variety of reasons, including domestic, industrial, leisure, landscape and agricultural uses,” Fritschi said. “In light of population increases and greater demands for non-agricultural water uses, more and more emphasis must be placed on efficient use of water resources for plant production. The drought simulators will provide us with a new tool to study how agricultural water use efficiency can be improved.”

Plant responses to drought are complex and difficult to study, says Robert (Bob) Sharp, a co-investigator and professor of plant sciences.

“The ability to manage the timing, duration and intensity of water-deficit stress under field conditions is essential to examine plant responses to drought,” he said. “Thus, the drought simulators will bridge the gap between controlled environment facilities, such as growth chambers and greenhouses, and real conditions encountered in the field.”

Other co-investigators in the project are MU plant sciences professors Robert Kallenbach, who studies forages that livestock eat, and Grover Shannon, a soybean expert. The project also includes 13 collaborators representing diverse disciplines such as water quality, soil biology, soil physics, plant-insect and plant-disease interactions, and plant breeding and genetics.

With the drought simulators in place, researchers may be able to:

  • develop new germplasm with increased drought tolerance;
  • discover genetic and physiological mechanisms that underlie drought adaptation in plants;
  • evaluate drought-related cultural practices that increase crop productivity; and
  • study the influence of water deficit stress on soil-plant-insect and soil-plant-pathogen interactions.

Drought, a continuing threat

Historical data show that some part of the United States experiences a severe drought every year. In 72 out of 100 years, from 1896 to 1995, more than 10 percent of the country was affected by severe or extreme drought. Currently, parts of the Great Plains west of Missouri River are considered to be in a drought.

In the Missouri River Basin, one part or another experienced drought in 90 out of the 100 years studied, according to the National Drought Mitigation Center. Costs such as lost farm income are estimated to reach between $200 million and $1.24 billion annually for the Great Plains alone and $6-8 billion for the U.S., reported a 1995 Federal Emergency Management Administration study.

The impact of drought not only affects crop production but also strikes associated industries, such as the $40 billion American beef cattle industry, which relies on grain crop production or forage to feed livestock

The impact of droughts on a global scale is extensive. Recurring droughts in the Horn of Africa have created ecological catastrophes, prompting massive food shortages and exacerbating political strife. The Darfur conflict, for example, is fueled by decades of drought, desertification and overpopulation.

Yield limitations caused by water-deficit stress are likely to intensify, as most global circulation models call for climate scenarios that will worsen drought in many regions, Fritschi said.

“Furthermore, the growing world population increasingly competes for fresh water resources and will require greater productivity per unit of water and land,” Fritschi said. “Increased irrigation using nonrenewable water sources and progressing desertification further underline the urgent need for crop varieties that produce greater yields in water-limited environments.”

Close to home, Fritschi anticipates a sizable economic impact from researchers’ development of more drought-tolerant plants.

“The value of Missouri crop and forage production amounted to more than $3.4 billion in 2006,” he said. “Increased plant productivity under drought conditions promises to have a significant positive effect on crop and forage yields, which will be magnified by any increased productivity on the $2.9 billion Missouri livestock industry.”

CAFNR draws on interdisciplinary research

“MU is becoming a significant center of excellence in drought research,” Sharp said. “Several scientists who have been recently recruited have expanded on long-standing strengths in drought research on the MU campus.”

These researchers, a collaborative team of university and USDA scientists, offer expertise from disciplines including plant physiology, plant breeding, molecular biology, biotechnology, entomology, agronomy, plant pathology, turfgrass science, forestry and soil science. They’ve worked with scientists in Missouri as well as Australia, England, India, Mexico, the Philippines and several countries in Africa.

Of particular note, Sharp said, several members of the group have expertise in the critically important but under-studied area of root biology— including Fritschi and Henry Nguyen, director of the National Center for Soybean Biotechnology housed at MU. Sharp has been studying the physiology of root growth under drought since he joined MU in 1986, and he recently received a grant from Monsanto to expand his research on root growth regulation in water-deficient maize.

Another area of emphasis in the project is tissue dehydration tolerance, which is the focus of Mel Oliver, research leader of the USDA Agricultural Research Service’s Plant Genetics Research Unit on the MU campus. Oliver is taking advantage of novel genetic determinants from desiccation-tolerant resurrection plants to improve dehydration tolerance in crop plants.

The rain shelters, he said, will provide a vital facility for these and other MU researchers to translate their basic discoveries of drought to the delivery of more drought-tolerant crops to the doorsteps of American farmers.

Researchers Involved in the MU Drought Project

Principle Investigator:
Felix B. Fritschi, assistant professor, plant physiology

Robert Sharp, professor, plant physiology
Robert Kallenbach, associate professor, livestock forage systems
J. Grover Shannon, professor, genetics and plant breeding

Steven Anderson, adjunct professor, soil physics
Deborah Finke, assistant professor, entomology
Robert Kremer, adjunct professor, microorganisms and weed control
Randall Miles, Director, Sanborn Field and Duley-Miller Research Plots
Henry Nguyen, professor, molecular genetics and biotechnology
Mel Oliver, adjunct professor, genomics and insect resistance
Craig Roberts, professor, forage quality and plant persistence
David Sleper, professor, soybean genetics
Gene Stevens, extension associate professor, field crop profitability
Kelly Tindall, research assistant professor, insect pests
William Wiebold, professor, soybean and corn management
J. Allen Wrather, professor, soybean and cotton disease management
Xi Xiong, assistant professor, turfgrass management