Risk of vine-to-vine spread of Xylella fastidiosa is greatest in July and August

December 07, 2020

The bacterial plant pathogen Xylella fastidiosa is a worldwide threat to perennial tree and vine crops and has been linked to Pierce's disease of grapevine in California, olive quick decline in Italy, and citrus variegated chlorosis in South America.

Scientists know that seasonality plays an important role in the spread of X. fastidiosa, but there are limited field data available. Scientists also know that epidemics of Pierce's disease in the southern San Joaquin Valley of California are associated with high abundance of the invasive glassy-winged sharpshooter that transmits X. fastidiosa.

"Managing the spread of X. fastidiosa is challenging due to a lack of field data on seasonal changes in vector abundance, proportion of vector population carrying the pathogen, and probability of acquisition from infected plants," explained Mark Sisterson, a vector entomologist with the Agricultural Research Service-USDA.

To gather more data, Sisterson and colleagues conducted a field study in the San Joaquin Valley to determine the time of year that vine-to-vine transmission of X. fastidiosa was most likely to occur. They found that grapevines were more likely to test positive for the pathogen in July and August than in spring. They also found that more glassy-winged sharpshooters tested positive for X. fastidiosa in July and August than in the spring.

"Accordingly, risk of vine-to-vine spread of X. fastidiosa is greatest in July and August," said Sisterson. "These findings will improve timing of insecticide applications to reduce glassy-winged sharpshooter populations, thereby reducing spread of X. fastidiosa."

Sisterson also notes that in other parts of California, studies have shown higher rates of vine recovery from infection over the winter when vines become infected during late summer compared to vines infected earlier in the season. Results from this study suggest that late season infections in the southern San Joaquin Valley are more likely to persist the following year and highlights the need for regionally specific data to inform vineyard management decisions.
-end-
To read more, go to "Xylella fastidiosa and Glassy-Winged Sharpshooter Population Dynamics in the Southern San Joaquin Valley of California" in the November issue of Plant Disease.

American Phytopathological Society

Related Pathogen Articles from Brightsurf:

Cell-autonomous immunity and the pathogen-mediated evolution of humans
Although immune responses are generated by a complex, hierarchical arrangement of immune system organs, tissues, and components, the unit of the cell has a particularly large effect on disease progression and host survival.

Microbial genetics: A protean pathogen
The bacterium Helicobacter pylori is linked to increased risk of stomach cancer, and is genetically highly variable.

"Winter is coming": The influence of seasonality on pathogen emergence
Seasonal fluctuations drive the dynamics of many infectious diseases. For instance, the flu spreads more readily in winter.

Fungal pathogen disables plant defense mechanism
Cabbage plants defend themselves against herbivores and pathogens by deploying a defensive mechanism called the mustard oil bomb.

The disease pyramid: Environment, pathogen, individual and microbiome
Researchers from the Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), the Université de Toulouse and the Helmholtz Centre for Environmental Research (UFZ) show how the microbial colonisation of the organism influences the interactions between living organisms, the environment and pathogens, using amphibians like frogs as examples.

Global spread of the multi-resistant pathogen Stenotrophomonas maltophilia
An international consortium found a remarkable global spread of strains of a multi-resistant bacterium that can cause severe infections - Stenotrophomonas maltophilia.

New information about the transmission of the amphibian pathogen, Bsal
Using existing data from controlled experiments and computer simulations, researchers with the University of Tennessee Institute of Agriculture have found that host contact rates and habitat structure affect transmission rates of Bsal among eastern newts, a common salamander species found throughout eastern North America.

New pathogen threatens fennel yield in Italy
A new fungal genus and species Ochraceocephala foeniculi causes fennel yield losses of about 20-30% for three different cultivars.

Study shows CRISPR effectiveness against colitis pathogen
Research at North Carolina State University shows that the CRISPR-Cas system can be used to effectively target and eliminate specific gut bacteria, in this case Clostridioides difficile, the pathogen that causes colitis -- a chronic, degenerative disease of the colon.

X-ray eyes peer deeper into deadly pathogen
In a new study, researchers at the Biodesign Center for Applied Structural Discovery and their international colleagues examine a key membrane protein responsible for the tularemia bacterium's prodigious ability to infect the body and cause illness.

Read More: Pathogen News and Pathogen Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.