scholarly journals First Report of A1 Mating Type of Phytophthora ramorum in North America

Plant Disease ◽  
2003 ◽  
Vol 87 (10) ◽  
pp. 1267-1267 ◽  
Author(s):  
E. M. Hansen ◽  
P. W. Reeser ◽  
W. Sutton ◽  
L. M. Winton ◽  
N. Osterbauer
Keyword(s):  
United States ◽  
Mating Type ◽  
North American ◽  
The United States ◽  
Phytophthora Ramorum ◽  
United States Department ◽  
Jackson County ◽  
Nursery Stock ◽  
Clackamas County ◽  
Microsatellite Alleles

Phytophthora ramorum is known in Europe and the western United States (1). In Europe, it is found in nurseries and landscape plantings. In the United States, it has been confined to coastal forests, and in California, it is found in a few horticultural nurseries. All European isolates tested have been A1 mating type, while all North American isolates were A2 mating type (2). Amplified fragment length polymorphism markers also indicated that the populations on the two continents are distinct, and nearly all North American isolates are from one clone (Kelly Ivors, unpublished). In June 2003, P. ramorum was isolated from diseased Viburnum and Pieris spp. cultivars from a Clackamas County nursery in northern Oregon and diseased Camellia sp. cultivar from a Jackson County nursery in southern Oregon. Representative isolates were submitted to the American Type Culture Collection, Manassas, VA. As part of the effort to determine the origin of these new infestations, we tested the nursery isolates for mating type. Seven Oregon nursery isolates, three Oregon forest isolates (from the predominant North American clone), and two European isolates were paired. Agar plugs from 3-day-old colonies were placed in close proximity on carrot agar plates, and then the plates were examined for oogonia after 3 and 10 days as advised by C. M. Brasier (personal communication). Oogonia and antheridia typical of P. ramorum (2) formed when isolates from the Clackamas County nursery were paired with the Oregon forest isolates and also when isolates from the Jackson County nursery were paired with the European isolates. Gametangia also formed in pairings between Oregon forest isolates and European isolates, but not in any other combinations. We developed polymerase chain reaction (PCR) primers for four microsatellite loci and determined allele sizes for the same set of isolates (unpublished). Microsatellite alleles of the Clackamas County isolates were identical to the European tester isolates, and alleles of the Jackson County isolates were identical to the Oregon forest isolates. These results indicate that the recent Oregon nursery infestations are of separate origins. The Clackamas County isolates are A1 mating type and have microsatellite alleles like the European testers, but according to shipping records, the nursery has received no host nursery stock directly from Europe. However, host nursery stock has been received from a Canadian nursery. The Jackson County isolates are of A2 mating type and have microsatellite alleles like the forest isolates of Oregon, which is consistent with the reported origin of these plants from a California nursery. These preliminary microsatellite results need to be validated against a larger isolate set but are congruent with the mating type results. The Oregon nursery infestations highlight the dangers of unregulated or underregulated transport of host nursery stock from infested areas to noninfested areas. All host plants from infested nursery blocks at the affected Oregon nurseries have been destroyed by incineration, and a monitoring program has been implemented. Other host nursery stock on site has been taken “off-sale” pending verification that it is disease free, per the United States Department of Agriculture, APHIS requirements. References: (1) J. M. Davidson et al. On-line publication. doi:10.1094/PHP-2003-0707-01-DG. Plant Health Progress, 2003. (2) S. Werres et al. Mycol. Res. 105:1155, 2001.

Estimated Economic Losses Associated with the Destruction of Plants Due to Phytophthora ramorum Quarantine Efforts in Washington State

2007 ◽  
Vol 8 (1) ◽  
pp. 20 ◽  
Author(s):  
Norman L. Dart ◽  
Gary A. Chastagner
Keyword(s):  
United States ◽  
The United States ◽  
Washington State ◽  
Phytophthora Ramorum ◽  
Economic Losses ◽  
United States Department ◽  
Department Of Agriculture ◽  
States Department ◽  
The Mean ◽  
Inspection Service

The number and retail value of plants destroyed in Washington State nurseries due to Phytophthora ramorum quarantine efforts was estimated using Emergency Action Notification forms (EANs) issued by the United States Department of Agriculture Animal and Plant Health Inspection Service between 2004 and 2005. Data collected from EANs indicate that during this period 17,266 containerized nursery plants were destroyed at 32 nurseries, worth an estimated $423,043. The mean loss per nursery was estimated at $11,188 in 2004, $11,798 in 2005, and at $13,220 per nursery over the 2-year period. Accepted for publication 26 January 2007. Published 8 May 2007.

Comparative Susceptibility of Plants Native to the Appalachian Range of the United States to Inoculation with Phytophthora ramorum

2007 ◽  
Vol 8 (1) ◽  
pp. 12 ◽  
Author(s):  
Robert G. Linderman ◽  
Patricia B. de Sá ◽  
E. Anne Davis
Keyword(s):  
United States ◽  
Plant Species ◽  
Mating Type ◽  
Management Practices ◽  
The United States ◽  
Phytophthora Ramorum ◽  
Eastern United States ◽  
Comparative Susceptibility ◽  
Climatic Characteristics ◽  
Inoculum Type

Phytophthora ramorum, cause of sudden oak death of trees or ramorum blight of other plant species, has an ever-increasing host range. Some geographic regions are considered to be at high risk of becoming infested with the pathogen, possibly causing plant mortality such as seen in native habitats of California and Oregon. One such region is the Appalachian range of the eastern United States, where known susceptible plants occur and climatic characteristics appear favorable for infections by this pathogen. We collected foliage of a range of plant species native to Appalachia in Kentucky during two summer seasons, and the foliage was shipped to Oregon for inoculation with P. ramorum to determine relative susceptibility. Leaves were needle-wounded and inoculated with either mycelium agar plugs or sporangia of a North American (A2 mating type) or European (A1 mating type) isolate. After 14 days incubation at 20°C in moist boxes, lesions caused by either inoculum type or isolate generally were comparable using digital photos and ASSESS software. Some genera, species, and cultivars within species were highly susceptible, while others were moderately susceptible or not susceptible. These results provide a basis for regional surveyors to select target hosts and to generate survey and management practices for nursery and forest areas. Accepted for publication 24 April 2007. Published 17 September 2007.

scholarly journals First Detection of Phytophthora ramorum Mating Type A2 in Europe

Plant Disease ◽  
2003 ◽  
Vol 87 (10) ◽  
pp. 1266-1266 ◽  
Author(s):  
Sabine Werres ◽  
Daphné De Merlier
Keyword(s):  
United States ◽  
The Netherlands ◽  
Mating Type ◽  
The United States ◽  
Phytophthora Species ◽  
Phytophthora Ramorum ◽  
Taxus Baccata ◽  
Camellia Japonica ◽  
Wide Range

Since its original isolation in 1993, Phytophthora ramorum has become an important pathogen. Initially, it was determined to be the causal agent of a twig blight of Rhododendron spp. in Germany and the Netherlands (3). Around the same period, symptoms and mortality on oak (Quercus spp.) and tanoak (Lithocarpus densiflorus) were associated with P. ramorum in California (2), where the disease was named sudden oak death. Subsequently, P. ramorum has been detected on a wide range of forest trees and shrub species in the United States. In Europe, the pathogen has spread to many countries, primarily on nursery plants of Rhododendron and Viburnum spp., and recently, on Camellia japonica, Kalmia latifolia, Pieris formosa var. forrestii, P. japonica, Leucothoe sp., Syringa vulgaris, and Taxus baccata. P. ramorum has not been observed in European forests. P. ramorum is heterothallic, and initial in vitro mating studies on agar media suggested that only the A1 mating type occurred in Europe, while only the A2 mating type was present in the United States (4). However, an isolate collected in 2002 in Belgium (1) appears to be the A2 mating type. This isolate (CBS 110901, Centraal Bureau voor Schimmelcultures, Baarn, the Netherlands) originated from an imported V. bodnantense plant at an ornamental nursery. A hyphal tip culture (BBA 26/02) of this isolate produced no oogonia on carrot piece agar after 6 weeks in pairing tests with other Phytophthora species of mating type A2. When paired with mating type A1 of P. cambivora, P. cinnamomi, P. cryptogea, and P. drechsleri, however, oogonia were observed in all pairings within 6 weeks. The number of oogonia was low in all pairings but was highest in pairings with P. cryptogea. No oospores were produced after 6 weeks between P. ramorum isolates BBA 26/02 and BBA 9/95 (from the holotype, mating type A1), but gametangia were observed when these isolates were paired on Rhododendron sp. twigs. Normal oogonia were produced on the outgrowing mycelium when pieces from these twigs were placed on carrot piece agar. The shape and size of the oogonia produced on carrot piece agar after pairing with P. cryptogea and on Rhododendron sp. twigs after pairing with P. ramorum BBA 9/95 were similar (24 to 34 μm, mean 29.6 μm and 25 to 33 μm, mean 30.6 μm, respectively). To our knowledge, this is the first observation of P. ramorum mating type A2 in Europe. References: (1) D. De Merlier et al. Plant Dis. 87:203, 2003. (2) D. M. Rizzo et al. Plant Dis. 86:205, 2002. (3) S. Werres et al. Mycol. Res. 105:1166, 2001. (4) S. Werres and B. Zielke. J. Plant Dis. Prot. 110:129, 2003.

Benjamin Henry Latrobe and the nomenclature of two North American fishes

1987 ◽  
Vol 14 (1) ◽  
pp. 85-88
Author(s):  
CHARLOTTE M PORTER
Keyword(s):  
United States ◽  
North American ◽  
The United States ◽  
American Shad ◽  
New Name ◽  
The Common ◽  
Fish Louse

A curious error affects the names of three North American clupeids—the Alewife, American Shad, and Menhaden. The Alewife was first described by the British-born American architect, Benjamin Henry Latrobe in 1799, just two years after what is generally acknowledged as the earliest description of any ichthyological species published in the United States. Latrobe also described the ‘fish louse’, the common isopod parasite of the Alewife, with the new name, Oniscus praegustator. Expressing an enthusiasm for American independence typical of his generation, Latrobe humorously proposed the name Clupea tyrannus for the Alewife because the fish, like all tyrants, had parasites or hangers-on.

Photovoltaics in the United States Department of Defense

1996 ◽  
Author(s):  
J. F. Hoelscher ◽  
R. Ducey ◽  
G. D. Smith ◽  
L. W. Strother ◽  
C. Combs
Keyword(s):  
United States ◽  
Department Of Defense ◽  
The United States ◽  
United States Department ◽  
States Department

scholarly journals “The Future of Archaeology Is Antiracist”: Archaeology in the Time of Black Lives Matter

2021 ◽  
pp. 1-20
Author(s):  
Ayana Omilade Flewellen ◽  
Justin P. Dunnavant ◽  
Alicia Odewale ◽  
Alexandra Jones ◽  
Tsione Wolde-Michael ◽  
...  
Keyword(s):  
United States ◽  
North American ◽  
The United States ◽  
Heritage Preservation ◽  
Social Unrest ◽  
Black Lives Matter ◽  
The North ◽  
Road Map ◽  
The Social ◽  
The Future

This forum builds on the discussion stimulated during an online salon in which the authors participated on June 25, 2020, entitled “Archaeology in the Time of Black Lives Matter,” and which was cosponsored by the Society of Black Archaeologists (SBA), the North American Theoretical Archaeology Group (TAG), and the Columbia Center for Archaeology. The online salon reflected on the social unrest that gripped the United States in the spring of 2020, gauged the history and conditions leading up to it, and considered its rippling throughout the disciplines of archaeology and heritage preservation. Within the forum, the authors go beyond reporting the generative conversation that took place in June by presenting a road map for an antiracist archaeology in which antiblackness is dismantled.

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