
via Oregon State University
A team led by Oregon State University scientists has developed a way to potentially thwart the spread of a disease-causing bacterium that harms more than hundred plant species worldwide, an advance that could save the nursery industry billions of dollars a year.
The research has important implications for commercial plant growers because it could help halt the spread of Agrobacterium. The bacterium causes crown-gall disease, which impacts more than 100 plant species, including fruit trees, roses, grape vine, nursery plants and shade trees. Those species have a combined value of more than $16 billion annually in the United States alone, according to the U.S. Department of Agriculture.
The methods developed for the study can also potentially be applied to track diseases in humans and animals and even foodborne disease outbreaks. For example, plasmids spread antibiotic-resistant genes, a pressing problem for human and animal health.
The Oregon State scientists worked with researchers at the USDA Agricultural Research Service on the study. The findings were just published in the journal Science.
“Understanding the genetic basis for how pathogens emerge and diversify in agricultural ecosystems is foundational for determining their spread and assessing risks,” said Jeff Chang, a professor in Oregon State’s College of Agricultural Sciences and one of the authors of the study. “These are critical to informing policies for improving plant health and preparing against disease outbreaks to increase global food security.”
The paper centers on plasmids, self-replicating DNA molecules that are found in Agrobacterium. Their spread amplifies the spread of disease. The plasmids of Agrobacterium have genes that give Agrobacterium the unique ability to transfer a portion of the plasmid into plant cells and genetically reprogram the host to cause crown-gall or hairy root disease.
These plasmids also have genes that allow Agrobacterium to transfer the entire plasmid horizontally from one bacterium to another rather than through vertical, or parent to child, inheritance. Upon acquiring a harmful plasmid, a previously benign strain of Agrobacterium can become a novel pathogen lineage. This ability makes control of the pathogen and tracking of an outbreak difficult. Thus, to develop their tracing system, the researchers first had to understand the evolution and classification of the plasmids.
Before this research, the accepted scientific view was that the frequent transfer of genetic information among plasmids and the large amount of genetic variation among Agrobacterium species made drawing evolutionary relationships between the two practically impossible. Without such information it’s not possible to accurately track disease outbreaks.
The researchers focused on two classes of plasmids, tumor inducing and root inducing, both of which provide Agrobacterium the ability to transfer a portion of the plasmid into plants and cause disease.
Melodie Putnam, director of the Oregon State Plant Clinic, and others at OSU and USDA-ARS provided hundreds of strains with plasmids from their well-curated collection and helped analyze the large datasets.
Alexandra Weisberg, lead author and a post-doctoral researcher co-mentored by Chang and Niklaus Grünwald, of the USDA-ARS Horticultural Crops Research Unit in Corvallis, sequenced 140 strains with plasmids and, surprisingly, found the plasmids all descended from just nine lineages.
“Armed with this extensive genetic sequencing information about how to classify plasmids and Agrobacterium, we could infer both how bacteria move among nurseries and how the plasmids move among bacteria,” Weisberg said.
Having whole genome sequences of Agrobacterium allowed the researchers to link nurseries on the basis of having strains with the same genome and plasmid sequences, the same genome sequence but different plasmid sequences, or different genome sequences but the same plasmid sequences, Weisberg said.
They were able to track at least seven cases in which global distribution of plants contributed to the widespread transmission of a single Agrobacterium strain-plasmid combination. One of these cases included a nursery that produces plants for wholesalers and may have served as a kind of patient zero source for many outbreaks. Strains of the same genotype-plasmid combination were later identified in two other nurseries in another part of the world.
With the ability to separately analyze the bacteria from the plasmid, the researchers found many cases in which plasmid transmission perpetuated disease spread. For example, they found one strain-plasmid combination that was collected in 1964. Plasmids with the same sequences were identified in strains collected 30 to 40 years later in different parts of the world.
A few strains of Agrobacterium, and some plasmids, have been modified and are used in tools for studying plant function, and for introducing new traits into plants. By characterizing the variation and relationships between plasmids, findings from this study also have potential applications in optimizing these biotechnology tools or developing new ones to advance research.
The Latest Updates from Bing News & Google News
Go deeper with Bing News on:
Plant disease
- NY farmworkers, food processing plant employees await COVID-19 vaccineon February 22, 2021 at 5:15 pm
New York dairy processors and farms hope their workers will soon have access to the COVID-19 vaccine. The New York Farm Bureau and Northeast Dairy Foods Association are among the groups advocating ...
- Covid-19 continues to cause delays and drive up costs for Georgia Power's expansion of Plant Vogtleon February 22, 2021 at 4:43 pm
The Covid-19 pandemic continues to impede Georgia Power’s progress on Plant Vogtle. The subsidiary of Southern Company (NYSE: SO) has faced multiple delays and unexpected expenses since construction ...
- John Oliver tries to spoil meat for us now by exposing unsafe meatpacking plantson February 22, 2021 at 8:21 am
John Oliver just won’t let us have anything nice. In this time of shut-in, shut-down COVID isolation, we’ve all learned to take our tiny pleasures where we can find them. After all, who could we ...
- Grape disease detection from the final frontieron February 22, 2021 at 7:20 am
Cornell’s Katie Gold is using the technology to study grape pathogens in New York state. (Courtesy NASA/Cornell University) Pathologist Katie Gold joined Cornell University last year to perform ...
- Eat Beyond adds Plant Power, California-Based Vegan QSR to its Portfolio, and Extends Marketing Agreementon February 22, 2021 at 6:00 am
Plant-Power is a leading quick service restaurant that is recognized as the vegan, healthy alternative to traditional fast-food restaurants ...
Go deeper with Google Headlines on:
Plant disease
Go deeper with Bing News on:
Tracing global spread of major plant disease
- Researchers using wastewater to track COVID-19 in Saskatoon, Indigenous communitieson February 22, 2021 at 4:44 pm
A project out of the University of Saskatchewan using wastewater to track COVID-19 in Saskatoon has received federal funding.
- Full transcript of "Face the Nation" on February 21, 2021on February 21, 2021 at 10:30 am
On this "Face the Nation" broadcast, National Security Adviser Jake Sullivan and Houston Mayor Sylvester Turner sat down with Margaret Brennan.
- Major vaccine manufacturers already researching, planning for COVID-19 variant spreadon February 19, 2021 at 9:47 pm
Even with the pace of vaccinations accelerating, some experts worry about a scenario where strains even more virulent than the one detected in South Africa start to emerge.
- Global Sage Herb Extract Market to be Driven by the Growth of the Herbal Medicine and Flavouring Spices Demand in the Forecast Period of 2021-2026on February 17, 2021 at 10:46 pm
The new report by Expert Market Research titled, 'Global Sage Herb Extract Market Size, Share, Price, Trends, Growth, Report and Forecast 2021-2026', gives an in-depth analysis of the global sage herb ...
- Manatee County part of effort to overcome concerns about the COVID-19 vaccineon February 11, 2021 at 9:00 pm
Vaccine hesitancy worries public health officials who fear that it could lead to more illness and make it difficult to achieve herd immunity, ...