First Report of <i>Diplodia quercivora</i> Causing Stem Cankers on Chestnut Oak (<i>Quercus montana</i>) in Maryland

Haines, Savannah L.; Stauder, Cameron M.; Martin, Danielle K.H.; Thompson, Bruce; Kasson, Matthew T.

doi:10.1094/pdis-11-18-1996-pdn

Cited by 6 publications

(9 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Additionally, Diplodia quercivora (Dq) was identified from Q. montana Willd. at one site in MD, providing the first confirmation of Dq causing disease on a white oak family member in the Mid-Atlantic region (Haines et al 2019). Prior to this discovery, Diplodia quercivora had been reported on southern live oak (Q. virginiana Mill.…”

Section: Introductionmentioning

confidence: 89%

“…These efforts resulted in the sampling of 31 forests in 16 counties (Supplemental Table 1). In addition to the counties stratified by mortality class, Green Ridge State Forest in Allegany County, MD and Seneca State Forest in Pocahontas County, WV were included to follow-up on the previous first detections of Dq in MD (Haines et al 2019) and Dc in WV . Using publicly available forest boundary .…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Morphological and Phylogenetic Resolution of Diplodia corticola and D. quercivora, Emerging Canker Pathogens of Oak (Quercus spp.), in the United States

et al. 2021

Self Cite

View full text Add to dashboard Cite

In Mediterranean Europe and the United States, oak species (Quercus spp.) have been in various states of decline for the past several decades. Several insect pests and pathogens contribute to this decline to varying degrees including Phytophthora cinnamomi, Armillaria spp., various insect defoliators, and additionally in the U.S., the oak wilt pathogen, Bretziella fagacearum. More recently, two emerging canker pathogens, Diplodia corticola (Dc) and Diplodia quercivora (Dq) have been implicated in causing dieback and mortality of oak species in Europe and in several regions in the United States. In 2019, a fungal survey was conducted in the Mid-Atlantic region of the Eastern U.S., including Maryland, Pennsylvania, Virginia, and West Virginia to determine the range and impact of Dc and Dq on forest health within the U.S. A total of 563 oak trees between red and white oak family members were evaluated across 33 forests spanning 18 counties. A total of 32 Diplodia isolates encompassing three Diplodia spp. were recovered from 5,335 total plugs collected from the 13 of 18 sampled counties. Recovered Diplodia species included Dc, Dq, and D. sapinea (Ds), as well as Botryosphaeria dothidea (Bd), a closely related canker pathogen in the Botryosphaeriaceae. Both Dc and Ds were recovered from red and white oak family members, whereas Dq was exclusive to white oak family members and Bd to red oak family members. Of these species, Dc was most frequently isolated followed by Dq, Ds, and Bd. Overall, mortality was relatively low across all sampled counties, indicating that these fungi, at the levels that were detected, are not widely inciting oak decline across the region, but more likely are acting opportunistically when the environment is conducive for disease. In an attempt to better understand the relationships among Dc and potentially their geographic origin(s), a multi-gene phylogenetic study and corresponding morphological study were conducted. A total of 49 Diplodia isolates from Spain, France, Italy, and the U.S. were assessed. Across all isolates and geographic regions, Dc formed a strongly supported monophyletic clade sister to Dq and included two strongly supported subclades, one that included isolates from Spain and California and a second that included isolates from Italy, Maryland, and West Virginia. Both subclades also exhibited overlapping spore measurements. These results support Dc as a cosmopolitan pathogen, native to both Europe and the U.S. with the possibility of secondary introductions.

show abstract

Section: Introductionmentioning

confidence: 89%

Section: Methodsmentioning

confidence: 99%

Morphological and Phylogenetic Resolution of Diplodia corticola and D. quercivora, Emerging Canker Pathogens of Oak (Quercus spp.), in the United States

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 89%

“…County, WV were included to follow-up on the previous first detections of Dq in MD (Haines et al 2019) and Dc in WV . Using publicly available forest boundary shapefiles, ArcGIS random plot generator created 30 labeled geographical coordinates (plots) per forest within each of the 33 forests.…”

Section: Green Ridge State Forest In Allegany County MD and Seneca Smentioning

confidence: 99%

“…Observed oak trees were micro-sampled on the main bole with a sterile bone marrow biopsy tool; a small 0.5 -1 mm diameter tool that penetrates the tree (approx. 1-2 mm) to excise outer bark tissues to the vascular cambium (Stauder et al 2019). A total of eight plugs were sampled per asymptomatic tree; four at DBH and four at approximately soil level in each of the cardinal directions.…”

Section: Green Ridge State Forest In Allegany County MD and Seneca Smentioning

confidence: 99%

See 1 more Smart Citation

Morphological and Phylogenetic Resolution ofDiplodia corticolaandD. quercivora, Emerging Canker Pathogens of Oak (Quercusspp.), in the United States

Ferreira

Stauder

Martin

et al. 2020

Preprint

View full text Add to dashboard Cite

In Mediterranean Europe and the United States, oak species (Quercus spp.) have been in various states of decline for the past several decades. Several insect pests and pathogens contribute to this decline to varying degrees including Phytophthora cinnamomi, Armillaria spp., various insect defoliators, and additionally in the U.S., the oak wilt pathogen, Bretziella fagacearum. More recently, two emerging canker pathogens, Diplodia corticola (Dc) andDiplodia quercivora (Dq) have been implicated in causing dieback and mortality of oak species in Europe and in several regions in the United States. In 2019, a fungal survey was conducted in the Mid-Atlantic region of the Eastern U.S., including Maryland, Pennsylvania, Virginia, and West Virginia to determine the range and impact of Dc and Dq on forest health within the U.S. A total of 563 oak trees between red and white oak family members were evaluated across 33 forests spanning 18 counties. A total of 32 Diplodia isolates encompassing three Diplodia spp.were recovered from 5,335 total plugs collected from the 13 of 18 sampled counties. Recovered Diplodia species included Dc, Dq, and D. sapinea (Ds), as well as Botryosphaeria dothidea (Bd), a closely related canker pathogen in the Botryosphaeriaceae. Both Dc and Ds were recovered from red and white oak family members, whereas Dq was exclusive to white oak family members and Bd to red oak family members. Of these species, Dc was most frequently isolated followed by Dq, Ds, and Bd. Overall, mortality was relatively low across all sampled counties, indicating that these fungi, at the levels that were detected, are not widely inciting oak decline across the region, but more likely are acting opportunistically when the environment is conducive for disease. In an attempt to better understand the relationships among Dc and potentially their geographic origin(s), a multi-gene phylogenetic study and corresponding morphological study were conducted. A total of 49 Diplodia isolates from Spain, France, Italy, and the U.S. were assessed. Across all isolates and geographic regions, Dc formed a strongly supported monophyletic clade sister to Dq and included two strongly supported subclades, one that included isolates from Spain and California and a second that included isolates from Italy, Maryland, and West Virginia. Both subclades also exhibited overlapping spore measurements.These results support Dc as a cosmopolitan pathogen, native to both Europe and the U.S. with the possibility of secondary introductions.

show abstract

Acute and Chronic Oak Decline in urban and forest ecosystems in Southern Italy

Carluccio,

Sabella,

Greco

et al. 2024

Forestry: An International Journal of Forest Research

View full text Add to dashboard Cite

Since recently, a decline of holm oak (Quercus ilex L.) is observed in Salento (South Italy), this caused concern regarding the protection of native biodiversity and local forests. Symptomatic trees show browning of leaves, thinning of canopy, and loss of branches. The aim of this study was to understand the biotic factors involved in the observed decline. During the monitoring activity, the use of phenotypic descriptors highlighted the presence of two types of decline with distinct symptoms among oaks in rural and urban areas, which could be classified as Acute Oak Decline (AOD) and Chronic Oak Decline (COD), respectively. Following this, diagnostic analyses were carried out to assess the presence of various holm oak pathogens on twigs, trunk, and soil. These analyses revealed the presence of several Botryosphaeriaceae oak pathogens, present ubiquitously between the two environmental contexts, with Diplodia seriata being overall the most prevalent. Contrarily, bacteria associated with AOD were only present in the rural areas and included: Brenneria goodwinii, Gibbsiella quercinecans, and Rahnella victoriana. As far as known to the authors, this is the first time these pathogens have been found in the Mediterranean coastal regions. Lastly, soil analyses performed to detect the presence of Phytophthora cinnamomi were negative. Our results highlight the presence of several pathogens, which indicates that oak decline is a multifactorial phenomenon for which the predisposing, initial, and contributing factors are not yet known particularly for the recently described AOD and COD. Finally, the identification of AOD-related bacteria in Salento is a cause of concern for the need of urgent management actions aimed to contain their spread and to preserve the forest heritage of the region.

show abstract

First Report of Diplodia quercivora Causing Stem Cankers on Chestnut Oak (Quercus montana) in Maryland

Cited by 6 publications

References 3 publications

Morphological and Phylogenetic Resolution of Diplodia corticola and D. quercivora, Emerging Canker Pathogens of Oak (Quercus spp.), in the United States

Morphological and Phylogenetic Resolution of Diplodia corticola and D. quercivora, Emerging Canker Pathogens of Oak (Quercus spp.), in the United States

Morphological and Phylogenetic Resolution ofDiplodia corticolaandD. quercivora, Emerging Canker Pathogens of Oak (Quercusspp.), in the United States

Acute and Chronic Oak Decline in urban and forest ecosystems in Southern Italy

Contact Info

Product

Resources

About