Posts Tagged: disease
Discolored leaves. Decaying roots. Dead wood. Mother Nature offers a fascinating and colorful backdrop of clues to track microscopic killers. Much like any medical mystery, experts are called in to diagnose or identify a disease from its symptoms and recommend management strategies to prevent further damage or loss of healthy plants.
Humans and animals depend on plants for their food supply and ultimately for their survival. When diseases threaten crops, a high-quality, affordable food supply is placed at risk. For growers, plant diseases can reduce crop yields. For consumers, reduced crop yields can drive higher food prices. Plant pathology research holds enormous implications for a sustainable food supply.
Florent Trouillas, who was named UC Cooperative Extension specialist in the Department of Plant Pathology at UC Davis and the Kearney Agricultural Research and Extension Center last year, explains the bottom line of most concern to growers.
"Once we identify a disease causal agent, a main question remains from growers. What growers really want to know is how to control the disease and prevent its spread to new healthy plants; they look to the University of California for solutions," Trouillas said.
A crisis in the food production system can impact other areas of society as well. In fact, history is filled with examples of how plant diseases influenced economies, environments and human societies.
Another historical illustration of plant pathology research occurred in the 1920s. The most common trees in the forests of the United States at the turn of the century were the majestic American chestnuts. The trees generated income for humans and the timber industry, served as a food source for people and animals, and provided habitat for wildlife. Then the trees started dying, until by the late 1920s, they had become the first tree in modern times on the brink of extinction. Plant pathologists were particularly adept at identifying plant diseases by this time and diagnosed the Cryphonectria parasitica fungus as the cause of the chestnut blight. By preventing the extinction of the pivotal species, plant pathology had a direct impact on the economy and the environment.
More recent major plant disease outbreaks in the United States involving plant pathology research have included Sudden Oak Death with devastating effects in California and Oregon forests, pitch canker killing California native pine species, and citrus canker in Florida, which has had a huge economic impact on the industry.
Veterinarians treat diseases in animals, physicians in humans. Trouillas describes the role of plant pathologists in similar terms. “We study the pathology of plant systems. Plant pathologists treat plants," he said.
Healthy plants ensure a sustainable food source and habitat for so many other organisms, including the human species.
According to a study conducted by Chantal Toledo and Sofia Berto Villas-Boas in an ARE Update published by UC Davis' Giannini Foundation of Agricultural Economics, consumers tend to respond to food scares and government warnings. This is consistent with a Sacramento Bee report announcing a 25 percent decrease in the sale of Foster Farms chicken. The study also suggests that, in the case of an outbreak, consumers don't always switch to alternative brands. The 2010 egg recall resulted in an overall drop in egg sales because consumers did not switch to alternative egg brands. Although it is too early to determine a change in overall chicken sales, Julia Thomas at the Sacramento Natural Foods Coop has reported a 10 percent increase in chicken sales since the salmonella outbreak. According to Thomas, foodborne disease outbreaks are good for the organic food movement.
The UC Davis School of Veterinary Medicine is planning a series of experiments to better understand Salmonella Heidelberg, the strain of salmonella found in Foster Farms Chicken, which has been a problem for the poultry industry in California and has been associated with human outbreaks since last year. Using molecular techniques, the experiments will study gene expression and determine a better characterization of the strains involved in the outbreak.
The School of Veterinary Medicine is also collaborating with the Animal Science Department at UC Davis and UC Cooperative Extension to leverage DNA sequencing in order to better understand the virulence of Salmonella Heidelberg and it's potential to cause disease under processing conditions.
Concerned about your own chickens? "The CAHFS Lab System routinely provides diagnostic support for commercial, small flock and backyard poultry producers in California," says Richard Breitmeyer, director of the the California Animal Health and Food Safety (CAHFS) Lab System at the UC Davis School of Veterinary Medicine, "including testing for salmonella." More information can be found on their website.
Roasted chicken. (Photo: Wikimedia Commons)