(Press-News.org) AMARILLO - Wheat streak mosaic virus is the most prevalent disease in the southwestern wheat producing region of the U.S., according to a Texas AgriLife Research scientist.
Dr. Charlie Rush, AgriLife Research plant pathologist in Amarillo, is assembling several teams of scientists to work on the disease from every aspect: vector to diagnosis and mapping to control.
"There are other diseases of concern, but wheat streak mosaic is always found somewhere in this wheat growing region, and every couple of years, we have an epidemic of it," Rush said.
Several issues cause the disease to be more problematic, he said. It is hard to distinguish the disease from drought or nutrient deficiencies because the symptoms often look very similar in all three. Also, the vector is so tiny it can't be seen in the field, so the disease is already present before it can be detected. And there are no chemical controls for either the insect or disease.
The disease doesn't just affect grain and forage yields, but also has a very negative impact on the ability of the wheat plant to use irrigation water, Rush said. Therefore, irrigation applied to diseased wheat wastes time, energy and groundwater.
Through a Texas Cropping Systems grant, work was started about a year ago to look at the factors that impact disease incidence and severity, primarily at the vector, which is the wheat curl mite, Rush said.
In this project, the focus is on trying to understand the dynamics of the wheat curl mite and what conditions cause it to move, said Jacob Price, a research associate working with Rush.
"We are monitoring the movement of the wheat curl mite where it lives on natural rangeland and Conservation Reserve Program grasses and monitoring movements on the southwest winds in the early spring and summer to wheat," Price said.
He said they want to find out where the mite populations live between seasons and if there are environmental factors that perpetuate the movement of the mite and the subsequent wheat viral diseases.
This project includes working with two private producers, as well as on the research farm, Price said. Grass is collected from the fields and the wheat curl mites are washed out and then tested individually to determine if they are carrying the wheat streak mosaic and triticum mosaic viruses.
"In doing so, we can find natural populations of wheat curl mite and determine where the diseases already exist in an area," he said. "Then we will use environmental data to determine if there are certain conditions that cause the mite to move and transport the disease to newly planted wheat fields."
In a separate study, Price planted an area of a wheat field in July and allowed it to become infested with the virus-carrying mites. Now he will plant the remainder of the field to wheat and monitor the movement.
"We want to know how fast they move; how high the populations are when they move; and how quickly we see disease development after a population of mites enters the field," he said.
Hopefully, Price said, this will help determine environmental factors that prompt movement and allow researchers to inform producers of the likelihood of high wheat streak mosaic infection in any given year.
"This will then allow producers to take certain precautions, such as delaying planting until the mites are no longer moving," he said. "Along with the new information and continued cultural practice of destroying volunteer wheat, we can help limit the risk of general wheat virus infection."
This information could help scientists design future research in pesticide application for the wheat curl mite, which is unknown at this time, Price said.
A separate project under way, funded by the Ogallala Aquifer Program, involves AgriLife Research and scientists with the U.S. Department of Agriculture-Agricultural Research Service at Bushland.
"We know from our previous work that wheat streak mosaic interferes with root development in wheat and restricts water-use efficiency," Rush said. "We also know that wheat streak is progressive and moves across fields.
"What we haven't been able to do," he said, "is to water one area of a field without wasting water on the area damaged by the disease."
Valmont Irrigation has been working with variable-rate nozzling systems for pivot irrigation units that will allow producers to adjust the amounts of water applied in different areas, Rush said. But the system needs a map of the field to tell it where to and where not to water.
"And if it is wheat streak they are dealing with, it's a moving target," Rush said. "So we have to get to a situation of real-time mapping."
Drs. Steve Evett and Susan O'Shaughnessy, USDA scientists at Bushland, have been working with remote sensing attached to the irrigation system to create these real-time maps.
But Rush said the system can't determine if the bad patch is due to a biotic stress, such as greenbugs or wheat streak mosaic, or if it is drought-stressed.
"The system may diagnose the disease as water stress and indicate it needs more water, when it doesn't," he said. "What we are going to do is help increase the precision of that remote sensing to allow them to differentiate a biotic stress from a droughty area."
Rush said his ultimate goal is to get a larger long-term grant from the federal Agriculture and Food Research Initiative program that will allow all the pieces of the research puzzle to be brought together. These grants are highly competitive and to be successful, they require multidisciplinary approaches that study entire agricultural systems.
"We want to be able to present an entire management system to farmers, with remote sensing, variable-rate nozzles, drought-tolerant and disease-resistant varieties of mainly corn and wheat, and specific agronomic practices," he said. "So the AFRI program is perfect for what we want to accomplish.
"We've been conducting pieces of research or laying a lot of bricks in the past for a foundation that we now can put together into one big system and bring it all together for the producers," Rush said.
###
END
DURHAM, N.C. – While scientists have spent the past 40 years describing the intricate series of events that occur when one mammalian cell divides into two, they still haven't agreed on how the process begins.
There are two seemingly contradictory theories, which now may be reconciled by a third theory being proposed by Duke University bioengineer Lingchong You. These findings could provide insights into the initiation of disease, such as cancer, which is marked by uncontrolled cell proliferation.
During proliferation, the DNA within the nucleus of a cell makes a copy ...
AMES, Iowa – A research team led by Edward Yu of Iowa State University and the Ames Laboratory has discovered the crystal structures of pumps that remove heavy metal toxins from bacteria, making them resistant to antibiotics.
The findings are published in the Sept. 23 issue of the journal Nature.
Yu – an Iowa State associate professor of chemistry, of physics and astronomy, of biochemistry, biophysics and molecular biology and an associate of the U.S. Department of Energy's Ames Laboratory – said the finding gives researchers a better understanding of bacterial resistance ...
MANHATTAN, KAN. -- With the concept of a store-within-a-store growing across the country, a Kansas State University researcher's work shows the increasing importance of brand reputation and its strong role in governing decisions.
Richard McFarland, associate professor of marketing, and four colleagues recently completed "Understanding Governance Decisions in a Partially Integrated Channel: A Contingent Alignment Framework." Their research will be published in the elite Journal of Marketing Research next year.
The research looks at separate companies who entered a store-within-a-store ...
A team from the National Museum of Natural Sciences (CSIC) has analysed the impact of climate change on spotted hyena survival in Europe over 10,000 years ago. These changes played an important role, but the scientists say studies are still needed to look at the influence of human expansion and changes in herbivorous fauna on the definitive extinction of this species across the continent.
"Climate change in the past was not directly responsible for the extinction of the spotted hyena in southern Europe, but it was a factor in its disappearance", Sara Varela, lead author ...
GREENBELT, Md. -- New supercomputer simulations tracking the interactions of thousands of dust grains show what the solar system might look like to alien astronomers searching for planets. The models also provide a glimpse of how this view might have changed as our planetary system matured.
"The planets may be too dim to detect directly, but aliens studying the solar system could easily determine the presence of Neptune -- its gravity carves a little gap in the dust," said Marc Kuchner, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Md. who led ...
"A giant rhino with a ridiculously supersized head."
"Fifteen long, pointed sideways oriented eye horns: one over the nose, one atop each eye, one at the tip of each cheek bone, and ten across the rear margin of the bony frill."
"A horned face: large horn over the nose and short, blunt eye horns that project strongly to the side."
Such phrases have been used to describe two newly discovered species of dinosaurs with looks only a mother could love. Still, they are drawing the attention and inspiring the imagination of scientists and lay people alike.
Announced today ...
COLUMBUS, Ohio – While birds living in urban areas face more predators than do those in rural areas, that doesn't mean urban birds face more danger from nest robbers.
A six-year study conducted in 19 central Ohio forests from 2004 to 2009 found that, as expected, rural areas that had higher numbers of nest predators such as raccoons, domestic cats, and crows, also showed lower rates of nest survival.
But there was no relation between the number of predators and nest survival in more urbanized areas.
Researchers believe that's because nest predators in urban areas ...
WASHINGTON -- A concerted effort to boost research on women's health over the last two decades has lessened the burden of disease and reduced deaths among women due to cardiovascular disease, breast cancer, and cervical cancer, says a new report from the Institute of Medicine. The effort has yielded less but still significant progress in reducing the effects of depression, HIV/AIDS, and osteoporosis on women, added the committee that wrote the report.
However, several health issues important to women have seen little progress, including unintended pregnancy, autoimmune ...
WASHINGTON -- A decade-long, multibillion dollar effort to restore the Florida Everglades has made tangible albeit slow progress, but additional projects need completion before substantial benefits are seen, says a new congressionally mandated report from the National Research Council. Challenges in achieving targets for both water quality and water flow have become more apparent, requiring further scientific analysis to determine the repercussions of trading off one for the other. Although important scientific advances have been made, continued decline of some aspects ...
Treatment with vitamin C rapidly improves the emotional state of acutely hospitalized patients, according to a study carried out by researchers at Montreal's Jewish General Hospital (JGH) and the affiliated Lady Davis Institute for Medical Research (LDI).
In a double-blind clinical trial, patients admitted to the JGH were randomly assigned to receive either vitamin C or vitamin D supplements for seven to ten days. Patients administered vitamin C had a rapid and statistically and clinically significant improvement in mood state, but no significant change in mood occurred ...