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:
- How the Columbian Exchange Brought Globalization—And Diseaseon August 25, 2021 at 8:13 am
Christopher Columbus’ arrival in the Caribbean in 1492 kicked off a massive global interchange of people, animals, plants and diseases between Europe and the Americas.
- UC Davis Study Finds Drought and Climate Change Shift Tree Disease in Sierra Nevadaon August 25, 2021 at 6:01 am
Climate change and drought are shifting how and where infectious plant disease moves in a forest. August 25, 2021 - By Kat Kerlin - Even pathogens have their limits. When it gets too hot or too dry, ...
- Drought and climate change shift tree disease in Sierra Nevadaon August 25, 2021 at 5:13 am
Even pathogens have their limits. When it gets too hot or too dry, some pathogens—like many living things—search for cooler, wetter and more hospitable climes. Ecologists have questioned if a warming, ...
- Discovery of mobile disease detectors in plants could boost crop resilienceon August 24, 2021 at 6:24 am
A study of how plants identify and react to invading pathogens using mobile disease detectors could help researchers breed disease-resistant crops.
- Is plant-based meat healthy?on August 24, 2021 at 5:00 am
Plant-based meat can be lower in saturated fat and calories than meat products, but it may be higher in sodium. However, it depends on the product type.
Go deeper with Google Headlines on:
Go deeper with Bing News on:
Tracing global spread of major plant disease
- Antibiotic use in medicine, agriculture led to increasing resistance in animals, study findson August 25, 2021 at 9:22 am
Increased use of antibiotics in medicine and agriculture from the 1950s through the 1990s led to a rise in resistance to the drugs among wild Swedish brown bears, a study published Wednesday by ...
- Global Smart Drug Delivery Drones Market with New Trends, Technology and Forecast to 2030 | Flirtey, Matternet, Softbox, Swoop-Aeroon August 18, 2021 at 5:53 am
reducing the spread of infection. Hence, the development of advanced drones, amidst growing prevalence of infectious diseases, is anticipated to fuel the growth of global smart drug delivery ...
- Coronavirus: Texas governor Abbott tests positive for Covid-19 - as it happenedon August 17, 2021 at 6:02 am
Texas’ Republican governor Greg Abbott has tested positive for Covid-19 amid a major surge of cases in the state that has stretched hospitals to capacity and sparked a bitter fight over mask mandates ...
- Inside America’s Covid-reporting breakdownon August 14, 2021 at 11:00 pm
Crashing computers, three-week delays tracking infections, lab results delivered by snail mail: State officials detail a vast failure to identify hotspots quickly enough to prevent outbreaks.
- Covid Updates: Oregon to Send National Guard Troops to Hospitalson August 13, 2021 at 1:43 pm
prohibited districts from “voluntarily adopting science-based strategies for preventing the spread of Covid-19 that are aligned with the guidance from the Centers for Disease Control and ...