<abstract xmlns="http://www.w3.org/1999/xhtml">The article is focused on microbiological and silvicultural properties of bacterial wetwood of silver birch (<italic>Betula pendula</italic>), also known as European white birch. During the active phase of the disease, bacterial wetwood (i.e. bacterial dropsy, vascular parenchymatous bacteriosis or flux slime) is characterised by crust and periderm bloating, necrotic wet stains and abundance of exudate. The disease is more likely to occur in older (<italic>r</italic> = 0.56, <italic>p</italic> &lt; 0.01) and less-dense (<italic>r</italic> = −0.29, <italic>p</italic> &lt; 0.01) stands.The statistical model showed that the chance of bacterial wetwood increases with birch age by 0.36% per year. The stands with birch proportion of over 70% demonstrated 15.3% lower infection rate compared to the stands with lower birch presence. The stands with lower stocking demonstrated a higher proportion of infected tree distribution by 7.5% compared to the stands with higher birch representation. The most vulnerable were larger, older <italic>B. pendula</italic> trees with longitudinally fissured bark that grow on poorer soils and experience frequent water stress.Birch associations with <italic>Pteridium aquilinum</italic> and <italic>Vaccinium myrtillus</italic> were more susceptible to infection (31.6% and 44.3%, respectively), whereas associations with <italic>Brachypodium sylvaticum, Sphagnum palustre</italic> and <italic>Calluna vulgaris</italic> were at lower risk. Strong ecological and trophic association of bacterial wetwood was present between silver birch and <italic>Tremex</italic> spp., particularly <italic>Tremex fuscicornis</italic>. Mycobiota was represented by <italic>Rhizopus microsporus, Mucor mucedo, Penicillium aurantiogriseum, Penicillium purpurogenum</italic> and <italic>Acremonium strictum</italic>.<italic>Enterobacter, Xanthomonas, Pantoea</italic> and <italic>Bacillus</italic> spp. associated with bacterial wetwood of silver birch were isolated. <italic>Enterobacter nimipressuralis</italic> was found to be the primary causative agent through means of artificial infection, while other bacteria were found to be either weak pathogens or concomitant. <italic>E. nimipressuralis</italic> formed the largest number of colony-forming units (CFU) for bark and cambium (164 and 127 CFU, respectively) and was also found in a small amount as a vital obligate in the automicrobiota in healthy birch trees.</abstract>

The article is focused on microbiological and silvicultural properties of bacterial wetwood of silver birch (Betula pendula), also known as European white birch. During the active phase of the disease, bacterial wetwood (i.e. bacterial dropsy, vascular parenchymatous bacteriosis or flux slime) is characterised by crust and periderm bloating, necrotic wet stains and abundance of exudate. The disease is more likely to occur in older (r = 0.56, p < 0.01) and less-dense (r = −0.29, p < 0.01) stands.The statistical model showed that the chance of bacterial wetwood increases with birch age by 0.36% per year. The stands with birch proportion of over 70% demonstrated 15.3% lower infection rate compared to the stands with lower birch presence. The stands with lower stocking demonstrated a higher proportion of infected tree distribution by 7.5% compared to the stands with higher birch representation. The most vulnerable were larger, older B. pendula trees with longitudinally fissured bark that grow on poorer soils and experience frequent water stress.Birch associations with Pteridium aquilinum and Vaccinium myrtillus were more susceptible to infection (31.6% and 44.3%, respectively), whereas associations with Brachypodium sylvaticum, Sphagnum palustre and Calluna vulgaris were at lower risk. Strong ecological and trophic association of bacterial wetwood was present between silver birch and Tremex spp., particularly Tremex fuscicornis. Mycobiota was represented by Rhizopus microsporus, Mucor mucedo, Penicillium aurantiogriseum, Penicillium purpurogenum and Acremonium strictum.Enterobacter, Xanthomonas, Pantoea and Bacillus spp. associated with bacterial wetwood of silver birch were isolated. Enterobacter nimipressuralis was found to be the primary causative agent through means of artificial infection, while other bacteria were found to be either weak pathogens or concomitant. E. nimipressuralis formed the largest number of colony-forming units (CFU) for bark and cambium (164 and 127 CFU, respectively) and was also found in a small amount as a vital obligate in the automicrobiota in healthy birch trees.

Bacterial wetwood of silver birch (<italic>Betula pendula</italic> roth): symptomology, etiology and pathogenesis

National University of Life and Environmental Sciences of Ukraine

Ukrainian Laboratory of Quality and Safety of Agricultural Products

Zhytomyr National Agroecological University

Folia Forestalia Polonica

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Bacterial wetwood of silver birch ( roth): symptomology, etiology and pathogenesis

The article is focused on microbiological and silvicultural properties of bacterial wetwood of silver birch (Betula pendula), also known as European white...

Bacterial wetwood of silver birch (Betula pendula roth): symptomology, etiology and pathogenesis

Published Online: Sep 18, 2020

Page range: 145 - 159

Received: Sep 25, 2019

Accepted: Jun 24, 2020

DOI: https://doi.org/10.2478/ffp-2020-0015

Keywords
artificial inoculation experiment, regression modelling, correlogram, integrated pest management, vital obligates, cause, symptoms, microbiota

© 2020 Anatoliy F. Goychuk et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Bacterial wetwood of silver birch (Betula pendula roth): symptomology, etiology and pathogenesis

Published Online: Sep 18, 2020

Page range: 145 - 159

Received: Sep 25, 2019

Accepted: Jun 24, 2020

DOI: https://doi.org/10.2478/ffp-2020-0015

Keywordsartificial inoculation experiment, regression modelling, correlogram, integrated pest management, vital obligates, cause, symptoms, microbiota

© 2020 Anatoliy F. Goychuk et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Keywords
artificial inoculation experiment, regression modelling, correlogram, integrated pest management, vital obligates, cause, symptoms, microbiota