ACHILLEA MILLEFOLIUM COMPLEX IN CANADA AND PORTIONS OF THE UNITED STATES

1959 ◽  
Vol 37 (1) ◽  
pp. 73-79 ◽  
Author(s):  
Gerald A. Mulligan ◽  
I. John Bassett

The chromosome numbers of plants of the Achillea millefolium complex from 27 locations in North America are reported. The levels of polyploidy found are correlated with diameters of the pollen grains. Measurements of pollen grains from more than 300 herbarium specimens are used as an indication of the occurrence of tetraploid and hexaploid species of Achillea in Canada. The results of some crossing experiments are also reported. It is concluded that the common Achillea of North America is tetraploid and is the native A. lanulosa Nutt. It extends from the Pacific to the Atlantic coasts, as far south as California in the west and Pennsylvania in the east, and to northern Canada and Alaska. Another native species, hexaploid Achillea borealis Bong., extends along the Pacific coast from southern California to the Aleutian Islands and along the northern shorelines of Alaska and Canada. A Eurasiatic hexaploid, A. millefolium L. s. str., has been sparingly introduced into Newfoundland, Prince Edward Island, Nova Scotia, and perhaps elsewhere along the Atlantic seaboard. In eastern Canada a male-sterile purple-flowered hexaploid also occurs. This hexaploid escapes from cultivation and forms localized patches. It undoubtedly has been selected from the Eurasiatic A. millefolium L. s str.

Plant Disease ◽  
2005 ◽  
Vol 89 (4) ◽  
pp. 380-384 ◽  
Author(s):  
Rick D. Peters ◽  
Rod J. Clark ◽  
Albert D. Coffin ◽  
Antony V. Sturz ◽  
David H. Lambert ◽  
...  

Pink rot of potato (Solanum tuberosum), caused by Phytophthora erythroseptica, is found wherever potatoes are grown, and in the last decade, it has reemerged as an economically important disease in Canada and the United States. A selection of isolates of P. erythroseptica from major potato-growing regions in North America, namely Prince Edward Island and New Brunswick, Canada, and Maine and Idaho, U.S.A., was assessed for genetic diversity with randomly chosen decanucleotide primers which were used to amplify regions of DNA to reveal polymorphisms among templates (random amplified polymorphic DNA [RAPD]). The isolates varied in their geographic origin as well as in their sensitivity to mefenoxam, as determined by an in vitro assay. In three separate RAPD screens (I, II, and III) with 23 isolates of P. erythroseptica chosen from a larger collection, 1,410, 369, and 316 robust, scorable bands were amplified, respectively. However, among the bands amplified in screens I, II, and III, only 3, 1, and 3 bands, respectively, were polymorphic. When three primers yielding polymorphisms were used to screen 106 isolates from Prince Edward Island and New Brunswick, or a representative collection of 32 isolates from Prince Edward Island, New Brunswick, Maine, and Idaho, no major variation was discovered. RAPD markers were not correlated with geographic origin or mefenoxam sensitivity of the isolates. From an evolutionary standpoint, the absence of genetic diversity among the isolates of P. erythroseptica we examined may be attributable to the relatively recent introduction of a small founding population of the pathogen in North America.


Plant Disease ◽  
2006 ◽  
Vol 90 (1) ◽  
pp. 112-112
Author(s):  
E. Lewis Roberts ◽  
J. F. White

Purple fountain grass (Pennisetum alopecuroides) is indigenous to Asia, prized for its foxtail-like purple flowers, and widely used as an ornamental. During October 1999, black choke disease was found on P. alopecuroides cv. Hameln (L.) Spreng at a plant nursery in Maryland. Disease symptoms include mummification of inflorescences by black conidial stromata, distorted leaf tissue, and a dense layer of white epiphytic mycelium on the adaxial leaves and culms. Stromata were initially white but became black with age. Microscopic analysis of the isolated fungus indicated that the causal organism was an Ephelis sp., American Type Culture Collection No. MYA-3317. The ephelidial conidia developed in sporodochia on stromata and were hyaline, filiform to acicular, and 18 to 21 × 1 μm. Cultures on potato dextrose agar were off-white and 50 mm in diameter after 14 days at 23°C. Analysis of herbarium specimens of several Balansia spp. revealed that the Ephelis sp. isolate bears morphological resemblance to Asian and not American Balansieae. In fact, the infection observed on Pennisetum sp. forms similarly to Ephelis sp. infection on Oryza sativa L. (Asian) that also results in development of stromata on panicles and a mycelial network enclosing the panicles, preventing maturation and expansion. On both plants, the infected inflorescence becomes black with age and appears mummified as pseudosclerotia form. Furthermore, flag leaves and tillers of both plants appear slightly distorted and silver due to the epibiotic mycelia. The causal agent of black choke disease on rice is Ephelis oryzae Syd. (teleomorph = Balansia oryzae-sativae Hashioka). The mature stroma of E. oryzae forms on the inflorescence and is embedded with a layer of ovate perithecia. Immature stromata bear conidiomata that are cupulate to cushion shaped and black, producing hyaline, branched conidiophores that terminate in phialides. Conidia are ephelidial, filiform to acicular, hyaline, and 18 to 22 × 1.5 μm (2). To determine the phylogenetic relationship between other balansioid fungi and the Ephelis sp. isolate, the nuclear ribosomal internal transcribed spacer (ITS1) region was amplified with primers ITS4 and ITS5 (3). Maximum parsimony analysis of the ITS1 sequences showed that the Ephelis sp. infecting P. alopecuroides cv. Hameln grouped (100% bootstrap support) in a clade with Ephelis oryzae, Balansia sclerotica, Balansia andropogonis, and Balansia sp.; all endemic to Asia and tightly groups with the Asian rice pathogen Ephelis oryzae (100% bootstrap support). Further phylogenetic analysis using topological constraints indicated that Ephelis sp. is not appropriately grouped with American balansioid species. Since P. alopecuroides is often imported to North America from Asia (1), it is likely that Ephelis sp. on P. alopecuroides is endemic to Asia and perhaps was transported along with its host to North America. The disease ontogeny, morphology, and sequence similarities between the Ephelis sp. isolated from Pennisetum sp. and E. oryzae suggests that these fungi are evolutionarily close, sibling species, or conspecific. To our knowledge, this is the first report of choke disease on P. alopecuroides in the United States. References: (1) A. S. Hitchcock. Manual of the Grasses of the United States. A. Chase, ed. U.S. Government Print Office, Washington DC, 1951 (2) F. N. Lee and P. S. Gunnell. Udbatta. Page 29 in: Compendium of Rice Diseases. R. K. Webster and P. S. Gunnell, eds. The American Phytopathological Society, St. Paul. MN, 1992. (3) J. F. White Jr. et al. Mycologia 89:408, 1997.


1967 ◽  
Vol 4 (6) ◽  
pp. 1185-1197 ◽  
Author(s):  
G. E. Rouse

Leaf compressions, spores, and pollen grains referrable to about 45 species were collected from a series of fine silts and coal stringers in the Parsnip River valley of the Rocky Mountain Trench. The leaf assemblage described in this paper indicates a late Maestrichtian to Danian age, somewhat younger than generally comparable assemblages previously reported from the lower part of the Edmonton Formation of Alberta, and from the Hell Creek, Lance, and Fox Hills Formations in the western interior of the United States. It also contains several species reported from the Nanaimo Group on eastern Vancouver Island. Plant microfossils (to be described in a later paper) include species of Glyptostrobus, Sciadopitys, Aquilapollenites, Pistillipollenites, Alnus, Myrica, Tilia, Pterocarya, and Carya, together with tricolpate pollen of uncertain affiliation. The combined leaf and microfossil assemblages indicate a warm mesothermal and humid paleoecological setting of low relief, suggesting absence of major mountain ranges westward to the Pacific Ocean.


1954 ◽  
Vol 11 (4) ◽  
pp. 454-471 ◽  
Author(s):  
E. Berkeley ◽  
C. Berkeley

Descriptions are given of the new genera Neopygospio (type N. laminifera, nov.) and Novobranchus (type N. pacificus, nov.); of the new species Nereis (Eunereis) wailesi, Spio butleri, Neopygospio laminifera, Novobranchus pacificus; and of the new variety pacificus of Distylia volutacornis (Montagu). All are from the Pacific coast of Canada. Synonymy is proposed of Lepidonotus caelorus Moore with L. squamatus (Linné), and of Goniada eximia Ehlers with Ophioglycera gigantea Verrill. In addition to the new species and variety, records of three species new to western Canada are presented, and notes on others. Thirteen species and a variety new to eastern Canada are recorded, one of them new to North America.


1957 ◽  
Vol 89 (12) ◽  
pp. 533-546 ◽  
Author(s):  
N. R. Brown ◽  
R. C. Clark

Early in the present century the balsam woolly aphid, Adelges piceae (Ratz.), was introduced accidentally into North America. The history of its development and spread in the United States and Canada has been described by Balch (1952). At the present time, the adelgid occurs in eastern Canada over approximately the southern half of New Brunswick with an extension of the range in the extreme northeastern part of the Province, throughout Nova Scotia and Prince Edward Island, and in some areas of the southwestern and southeastern parts of Newfoundland.


2015 ◽  
Vol 15 (22) ◽  
pp. 33209-33251
Author(s):  
J. Feng ◽  
H. Liao ◽  
J. Li

Abstract. The Pacific-North America teleconnection (PNA) is the leading general circulation pattern in the troposphere over the region of North Pacific to North America during wintertime. This study examined the impacts of monthly variation of the PNA phase (positive or negative phase) on wintertime surface-layer aerosol concentrations in the US by analyzing observations during 1999–2013 from the Air Quality System of Environmental Protection Agency (EPA-AQS) and the model results for 1986–2006 from the global three-dimensional Goddard Earth Observing System (GEOS) chemical transport model (GEOS-Chem). The composite analyses on the EPA-AQS observations over 1999–2003 showed that the average concentrations of PM2.5, sulfate, nitrate, ammonium, organic carbon, and black carbon aerosols over the US were higher in the PNA positive phases than in the PNA negative phases by 1.4 μg m−3 (12.7 %), 0.1 μg m−3 (6.4 %), 0.3 μg m−3 (39.1 %), 0.2 μg m−3 (22.8 %), 0.8 μg m−3 (21.3 %), and 0.2 μg m−3 (34.1 %), respectively. The simulated geographical patterns of the differences in concentrations of all aerosol species between the PNA positive and negative phases were similar to observations. Based on the GEOS-Chem simulation driven by the assimilated meteorological fields, the PNA-induced variation in planetary boundary layer height was found to be the most dominant meteorological factor that influenced the concentrations of PM2.5, sulfate, ammonium, organic carbon, and black carbon, and the PNA-induced variation in temperature was the most important parameter that influenced nitrate aerosol. Results from this work have important implications for understanding and prediction of air quality in the United States.


FACETS ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 238-253
Author(s):  
D. T. Tyler Flockhart ◽  
Maxim Larrivée ◽  
Kathleen L. Prudic ◽  
D. Ryan Norris

Monarch butterflies ( Danaus plexippus, Linnaeus, 1758) are comprised of two migratory populations separated by the Rocky Mountains and are renowned for their long-distance movements among the United States, Canada, and Mexico. Both populations have declined over several decades across North America prompting all three countries to evaluate conservation efforts. Monitoring monarch distribution and abundance is a necessary aspect of ongoing management in Canada where they are a species at risk. We used presence-only data from two citizen science data sets to estimate the annual breeding distribution of monarch butterflies in Canada between 2000 and 2015. Monarch breeding distribution in Canada varied widely among years owing to natural variation, and when considering the upper 95% of the probability of occurrence, the annual mean breeding distribution in Canada was 484 943 km2 (min: 173 449 km2; max: 1 425 835 km2). The area of occurrence was approximately an order of magnitude larger in eastern Canada than in western Canada. Habitat restoration for monarch butterflies in Canada should prioritize productive habitats in southern Ontario where monarchs occur annually and, therefore, likely contribute most to the long-term viability of monarchs in eastern North America. Overall, our assessment sets the geographic context to develop successful management strategies for monarchs in Canada.


2021 ◽  
Author(s):  
Christian Schmidt ◽  
Alexandre Anctil

The geometrid moth Hemithea aestivaria (Hübner, 1789) was introduced from Europe to North America, first detected in British Columbia in 1973. Until 2019, its North American range was limited to a restricted area of the Pacific Northwest. Here, we report on the first records of H. aestivaria for eastern North America from three widely separated urban centers in eastern Canada during 2019-2020.


1964 ◽  
Vol 54 (1) ◽  
pp. 295-346
Author(s):  
Maurice W. Major ◽  
George H. Sutton ◽  
Jack Oliver ◽  
Robert Metsger

abstract Observations of earth strains, covering a wide spectrum of periods, have been made with a three component installation located 1800 feet below the surface in a deep mine at Ogdensburg, New Jersey. This paper is a description of the strain meters and their environment and is a report of several studies based largely on strain observations. The instruments, modeled after those of Benioff, employ quartz tubes as their standard of length, use variable capacitor transducers, and record simultaneously tidal data at low gain and seismic data at a sensitivity about 40 times that of the tidal signal. A significant reduction of the noise level in the seismic spectrum has been achieved by sealing the tube rooms against air pressure fluctuations. The present secular strain rate is less than 1.7 × 10−8 per month, almost an order of magnitude less than that observed by Benioff in California, and almost two orders of magnitude less than that observed by Takada in Japan. A transient strain with a duration of about 100 hours was associated with the storm tide which damaged the eastern coast of the United States on March 5-8, 1962. The strain corresponds to that produced by an anomalous high water mass whose seaward extent was limited to 100 ± 30 km in the azimuth southeast from Sandy Hook. Direct observation of the seaward extent of such storm tides, for areas off coastlines bordering the open ocean, has not been possible in the past because of the lack of deep water tide recorders. Love's number h and Shida's number l are determined to be 0.53 and 0.037, respectively, from observations of strains associated with the M2 tidal constituent, on the basis of the assumption that the ocean load generated strain has the same phase on both horizontal instruments. The uncertainty in h and l is large, as it is in other measurements of these numbers, because of the effect of ocean load. This uncertainty is examined in a quantitative manner by mapping h and l as functions of ocean load amplitude and phase in the vicinity of the solution. Strain seismograms of the Kenai Peninsula earthquake of September 5, 1961, and the Prince Edward Island earthquake of December 29, 1961, are unique. The exceptional long period response of the strain seismometers has made it possible to record, on the first pass, waves associated with the group velocity maximum of the Rayleigh wave dispersion curve over a purely continental path across North American and an almost pure oceanic path across the Atlantic. Such data have never before been reported. The shield area of North America is characterized by higher than average Rayleigh wave velocities. The Atlantic data, when compared with data from the Pacific, do not indicate any appreciable difference between the mantle structure below the Atlantic and that below the Pacific.


1990 ◽  
Vol 122 (3) ◽  
pp. 579-581 ◽  
Author(s):  
R.W. Kieckhefer ◽  
N.C. Elliott

Coccinellids are a conspicuous group of aphidophagous predators in maize, Zea mays L., in the Northern Great Plains of the United States. Numerous studies have been conducted on the ecology of coccinellids in maize in North America (Ewert and Chiang 1966a, 1966b; Smith 1971; Foott 1973; Wright and Laing 1980; Corderre and Tourneur 1986; Corderre et al. 1987). However, there have been few long-term surveys of coccinellids in maize. Foott (1973) reported on the abundance of coccinellid species inhabiting maize in eastern Canada over a 4-year period; no surveys of this type have been reported for the Northern Great Plains. We sampled coccinellids in maize fields at three sites in eastern South Dakota for 13 consecutive years to determine the species inhabiting the crop and levels of variation in their abundances among sites and years.


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