Pseudomonas avellanae: From Specific Pathogens to a Species Complex.
- 1CREA, Research Centre for Olive, Fruit and Citrus Crops, Rome, Italy.
- 2Institute for Plant Protection and Environment, Belgrade, Serbia.
- 3Faculty of Agriculture, University of Novi Sad, Novi Sad, Serbia.
Abstract
Taxonomy
Bacteria; Proteobacteria, gamma subdivision; Order Pseudomonadales; Family Pseudomonadaceae; Genus Pseudomonas; Pseudomonas avellanae species complex, which includes different pathogenic lineages previously classified within the P. syringae complex, namely the pathovars avellanae, theae, actinidiae, and morsprunorum race 2.Microbiological properties
As a whole, the P. avellanae species complex genome comprises 19.4% conserved genes and 80.6% flexible genome. Mobile genetic elements are present within the complex. Strains associated with bacterial canker of European hazelnut possess two plasmids, whereas multiple plasmids and megaplasmids can occur in the lineages associated with bacterial canker of kiwifruit and cherry. Fourteen type III secretion system effectors are shared by all lineages of the species, and each lineage apparently possesses specific effector proteins. Phytotoxins, such as phaseolotoxin, coronatine, and tabtoxin, can be produced by some lineages of P. avellanae. Siderophores are present in the P. avellanae species complex.Host range
Corylus avellana, Camellia sinensis var. sinensis, Actinidia chinensis var. chinensis, A. chinensis var. deliciosa, Prunus avium, P. cerasus, P. domestica. A strain of P. avellanae has also been isolated from river epilithon.Disease symptoms
Pseudomonas avellanae can cause severe symptoms, including bud necrosis (kiwifruit), leaf necrosis and wilting (hazelnut, tea, kiwifruit, cherry/plum), shoot and twig blight (hazelnut, tea, kiwifruit, cherry/plum), flower necrosis (kiwifruit), fruit necrosis (cherry/plum), trunk canker (hazelnut, kiwifruit, cherry/plum), and plant death (hazelnut, tea, kiwifruit).Epidemiology
Some P. avellanae lineages are favoured by air temperatures below 0°C. Penetration mainly occurs through stomata, leaf scars, and wounds induced by frost events. P. avellanae species complex exhibits both epiphytic and endophytic phases. During summer, very high temperatures can reduce the multiplication and dispersal of the pathogen. The global circulation of latently infected propagative plant material largely favours the spread of P. avellanae lineages across different cultivation areas.Detection
Pathogens belonging to this complex can be detected in both symptomatic and asymptomatic plant tissues (e.g., twigs, buds, and cankers) using various conventional techniques and molecular tools (standard-, duplex-, TaqMan-, real-time PCR, LAMP, MLSA). Depending on the targeted symptoms, pathogenicity tests may be conducted on leaf, leaf scars or woody tissues.Disease control
Disease management is based on spray treatments to the crown using copper compounds applied in spring and autumn, as well as after harvest, during leaf fall, and following hail, frost events, and pruning. Balanced plant nutrition is important to reduce the risk of severe infection. Alternative promising strategies include the application of biocontrol agents, natural products, and bacteriophages.
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BibTeX
@article{scortichini2026pseudomonas,
title = {{Pseudomonas avellanae: From Specific Pathogens to a Species Complex.}},
author = {Marco Scortichini and Tatjana Popović Milovanović and Renata Iličić},
journal = {Molecular plant pathology},
year = {2026},
month = oct,
doi = {10.1111/mpp.70357},
url = {https://europepmc.org/article/MED/42897898},
note = {CC BY},
}
RIS
TY - JOUR
TI - Pseudomonas avellanae: From Specific Pathogens to a Species Complex.
AU - Marco Scortichini
AU - Tatjana Popović Milovanović
AU - Renata Iličić
PY - 2026
DA - 2026/10/01
JO - Molecular plant pathology
DO - 10.1111/mpp.70357
UR - https://europepmc.org/article/MED/42897898
AB - Taxonomy Bacteria; Proteobacteria, gamma subdivision; Order Pseudomonadales; Family Pseudomonadaceae; Genus Pseudomonas; Pseudomonas avellanae species complex, which includes different pathogenic lineages previously classified within the P. syringae complex, namely the pathovars avellanae, theae, actinidiae, and morsprunorum race 2.Microbiological properties As a whole, the P. avellanae species complex genome comprises 19.4% conserved genes and 80.6% flexible genome. Mobile genetic elements are present within the complex. Strains associated with bacterial canker of European hazelnut possess two plasmids, whereas multiple plasmids and megaplasmids can occur in the lineages associated with bacterial canker of kiwifruit and cherry. Fourteen type III secretion system effectors are shared by all lineages of the species, and each lineage apparently possesses specific effector proteins. Phytotoxins, such as phaseolotoxin, coronatine, and tabtoxin, can be produced by some lineages of P. avellanae. Siderophores are present in the P. avellanae species complex.Host range Corylus avellana, Camellia sinensis var. sinensis, Actinidia chinensis var. chinensis, A. chinensis var. deliciosa, Prunus avium, P. cerasus, P. domestica. A strain of P. avellanae has also been isolated from river epilithon.Disease symptoms Pseudomonas avellanae can cause severe symptoms, including bud necrosis (kiwifruit), leaf necrosis and wilting (hazelnut, tea, kiwifruit, cherry/plum), shoot and twig blight (hazelnut, tea, kiwifruit, cherry/plum), flower necrosis (kiwifruit), fruit necrosis (cherry/plum), trunk canker (hazelnut, kiwifruit, cherry/plum), and plant death (hazelnut, tea, kiwifruit).Epidemiology Some P. avellanae lineages are favoured by air temperatures below 0°C. Penetration mainly occurs through stomata, leaf scars, and wounds induced by frost events. P. avellanae species complex exhibits both epiphytic and endophytic phases. During summer, very high temperatures can reduce the multiplication and dispersal of the pathogen. The global circulation of latently infected propagative plant material largely favours the spread of P. avellanae lineages across different cultivation areas.Detection Pathogens belonging to this complex can be detected in both symptomatic and asymptomatic plant tissues (e.g., twigs, buds, and cankers) using various conventional techniques and molecular tools (standard-, duplex-, TaqMan-, real-time PCR, LAMP, MLSA). Depending on the targeted symptoms, pathogenicity tests may be conducted on leaf, leaf scars or woody tissues.Disease control Disease management is based on spray treatments to the crown using copper compounds applied in spring and autumn, as well as after harvest, during leaf fall, and following hail, frost events, and pruning. Balanced plant nutrition is important to reduce the risk of severe infection. Alternative promising strategies include the application of biocontrol agents, natural products, and bacteriophages.
SN - 1364-3703
ER -