Navigation Links
Grazing animals help spread plant disease
Date:12/29/2008

CORVALLIS, Ore. Researchers have discovered that grazing animals such as deer and rabbits are actually helping to spread plant disease quadrupling its prevalence in some cases and encouraging an invasion of annual grasses that threaten more than 20 million acres of native grasslands in California.

The findings run contrary to what had been predicted by other theories, which had suggested that "consumers" such as deer would help to contain or reduce disease. They point once again to the complexity of natural ecosystems and the many ways in which plants, animals and even viruses interact with each other.

The work will be published this week in Proceedings of the National Academy of Sciences, by researchers from Oregon State University, Cornell University and the University of North Carolina.

"We usually think of a disease and its host as very tightly coupled, like a flu virus that infects humans," said Elizabeth Borer, an assistant professor of zoology at OSU. "But in natural ecosystems we're finding it's not nearly that simple, and to understand how plant pathogens work we have to consider the entire food web and many plant/animal interactions of which we are barely aware."

The work is of particular importance, researchers said, because so many elements of ecosystems are undergoing rapid change, from human manipulation, climate change, increase or decrease in various species, new invasive species, and other factors. Any one of those changes could have ripple effects with seemingly unrelated diseases or other issues that are poorly understood an increase in the abundance of white-footed mice, for instance, has been shown to increase Lyme disease risk in humans.

In this study, scientists examined the effect of herbivores and omnivores such as mule deer, rabbits and feral pigs on the prevalence of barley and cereal yellow dwarf viruses, which can infect more than 100 crop and non-crop plant species, reducing their growth and seed yield. This virus is a major concern for cereal crop production around the world.

In places where most plant eaters were kept out of test plots, the prevalence of this virus was only about 5 percent. It rose to 18 percent, a 3.6-fold increase, in areas that the animals grazed.

The grazers did not directly spread the plant virus, researchers said. Rather, they increased the amounts of annual grasses that are preferred by the aphids which play a role in transmission of this viral plant disease. That allowed for a much greater prevalence of the virus in areas where grazing took place.

"Even in complex natural communities, alternations to food web composition such as consumer invasion or extinction can lead to significant impacts that cascade through entire communities, including changes in infection risk," the researchers wrote in their report.


'/>"/>

Contact: Elizabeth Borer
borer@science.oregonstate.edu
541-737-3701
Oregon State University
Source:Eurekalert

Related biology news :

1. Novel technique for fluorescence tomography of tumors in living animals
2. Details of evolutionary transition from fish to land animals revealed
3. Researchers note differences between people and animals on calorie restriction
4. Gene associated with pair-bonding in animals has similar effects in human males
5. Using networks to map the social lives of animals
6. Big-brained animals evolve faster
7. Closing the gap between fish and land animals
8. Genomics of large marine animals showcased in the biological bulletin
9. How can we measure the emotional states of animals?
10. Road losses add up, taxing amphibians and other animals
11. Are animals stuck in time?
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/3/2016)... 3, 2016 Vigilant Solutions announces today that ... Missouri solved two recent hit-and-run ... data from Vigilant Solutions. Brian Wenberg ... the victim was walking out of a convenience store and witnessed an elderly ... his vehicle, striking his vehicle and leaving the scene.  ...
(Date:2/2/2016)... YORK , Feb. 2, 2016 ... of the bioinformatic market by reviewing the recent ... enabled tools that drive the field forward. Includes ... to: Identify the challenges and opportunities that ... providers and software solution developers, as well as ...
(Date:2/2/2016)... Va. , Feb. 2, 2016   ... award from the U.S. Army Research Office and ... the range and sensitivity of the company,s ... Past Accounting Mission and, more generally, defense-related DNA ... DNA phenotyping capabilities (predicting appearance and ancestry from ...
Breaking Biology News(10 mins):
(Date:2/10/2016)... /PRNewswire/ - BioAmber Inc. (NYSE: BIOA ), a ... Mitsui & Co. Ltd., its partner in the ... investing an additional CDN$25 million in the joint venture ... 30% to 40%.  Mitsui will also play a stronger ... Sarnia , providing dedicated resources alongside ...
(Date:2/10/2016)... , Feb. 10, 2016 NX Prenatal ... its proprietary NeXosome® technology for early warning of ... its most recent study by Dr. Thomas ... the Society for Maternal Fetal Medicine,s (SMFM) annual meeting ... 1-6 th , 2016.  The presentation reported initial ...
(Date:2/10/2016)... 10, 2016  IsoRay, Inc. (NYSE MKT: ISR), a ... medical radioisotope applications for the treatment of prostate, brain, ... its financial results for the second quarter and six ... --> --> ... fiscal 2016, which ended December 31, 2015, a 12% ...
(Date:2/10/2016)... , ... February 10, 2016 , ... ... three states, announced today the promotion of two long-standing principal investigators (PI) to ... Family Medicine, Clinical Research and Development. , Dr. Laurence Chu, a Benchmark Research ...
Breaking Biology Technology: