Drought simulators aid crop research
In agriculture, a dearth of rainfall can be devastating. Droughts are the leading cause of crop failure. They can increase consumer costs, kill livestock, reduce crop yields, and trigger wildfires and dust storms. Mizzou scientists hope to reduce the damage.
At the University of Missouri’s Bradford Research and Extension Center, researchers are working with two new drought simulators designed to test the effects of water deficiency on crops. The simulators are part of a $1,558,125 Missouri Life Sciences Research Board grant to study how reduced water availability affects plants and crop productivity as well as how new breeds of drought-tolerant plants can boost yields.
Researchers in MU’s College of Agriculture, Food and Natural Resources (CAFNR) will use the simulators to vary the amount of water test plants receive, mimicking everything from short dry spells to persistent and severe drought conditions.
The simulators 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. By varying the position of the greenhouse, researchers can allow a specified amount of rain to fall on the plants. Test plots of the same plants just outside the drought simulators provide a scientific control.
Missouri crop studies
When funding allows, additional simulators will be built at the Delta Research Center, Portageville, in the southeastern part of the state and at the Horticulture and Agroforestry Research Center, New Franklin.
The locations represent Missouri’s varied environments, crop species and soil types. This placement allows researchers to test any agriculturally important crop, forage or turf species grown in Missouri and surrounding states.
“This project will create a network of drought simulators unlike any other in America, providing Missouri scientists with state-of-the-art field facilities to conduct a broad range of drought-related translational research," says Felix Fritschi, the plant sciences assistant professor 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."
Drought conditions this growing season have occurred nearby in Kansas, and severe droughts have plagued almost all of Oklahoma and Texas.
“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 says. “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.”
A global scourge
Historical data indicate 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. Parts of the Missouri River Basin experienced drought in 90 out of the 100 years studied, according to the National Drought Mitigation Center.
The impact of droughts on a global scale is extensive, Fritschi says. 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 says.
"Furthermore, the growing world population increasingly competes for fresh water resources and will require greater productivity per unit of water and land,” Fritschi says. “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."
The new simulators are critical in drought research. Plant responses to drought are complex and currently difficult to study, says plant sciences professor Bob Sharp, a co-investigator and the new director of MU’s Interdisciplinary Plant Group.
“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 says. “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.”
Co-investigators in the project include MU plant sciences professors Robert Kallenbach, who studies the forages that livestock eat, and Grover Shannon, a soybean expert. The 13 collaborators on the project represent diverse disciplines such as water quality, soil biology, soil physics, plant-insect and plant-disease interactions, and plant breeding and genetics.
The drought simulators will allow researchers 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.
- Study the influence of water deficit stress on soil-plant-insect and soil-plant-pathogen interactions.
MU and USDA researchers are working with other scientists in Missouri, as well as in Australia, England, India, Mexico, the Philippines and several countries in Africa, on collaborative research. Members' specialties include plant physiology, plant breeding, molecular biology, biotechnology, entomology, agronomy, plant pathology, turfgrass science, forestry and soil science.
Fritschi and Sharp, along with endowed professors of soybean biotechnology Gary Stacey and Henry Nguyen, offer expertise in the under-studied area of root biology. Nguyen serves as director of the National Center for Soybean Biotechnology at MU, and Sharp is collaborating with Monsanto to expand his research on root growth regulation in water-deficient maize. Mel Oliver, research leader of the USDA Agricultural Research Service’s Plant Genetics Research Unit, is studying the genetic characteristics of desiccation-tolerant plants that could be used to improve dehydration tolerance in important commercial crops.
The drought simulators provide a vital facility for researchers to develop drought-tolerant crops — and positively affect the region's economy.
Drought affects not only crop production but also associated industries, such as the $40 billion American beef cattle industry, which relies on grain crop production or forage to feed livestock.
"The value of Missouri crop and forage production amounted to more than $3.4 billion in 2006,” Fritschi says. “Increased plant productivity under drought conditions promises to have a significant positive effect on crop and forage yields.”