Differences between North American and European Populations of Balanus balanoides Revealed by Transplantation

1968 ◽  
Vol 25 (12) ◽  
pp. 2633-2641 ◽  
Author(s):  
D. J. Crisp
Keyword(s):  
North American ◽  
The North ◽  
North Wales ◽  
Time Of Breeding ◽  
Lower Temperature ◽  
Balanus Balanoides ◽  
European Form ◽  
American Form ◽  
European Populations

Transplants of specimens of Balanus balanoides from North Wales to Newfoundland, Canada, confirmed two innate differences between European and North American forms of the species. Breeding took place later in transplanted European populations. The eggs of the European form, though maturing later and therefore at a slightly lower temperature than the North American form, were distinctly smaller.The time of breeding both in the North American and European forms was earlier at higher latitudes, at higher shore levels, and in shelter.

scholarly journals Tasserkidrilus cf. americanus (Clitellata, Naididae) – A new record from Slovakia confirms the dissimilarity between the European and North American populations

2021 ◽  
Vol 9 ◽  
Author(s):  
Igor Kokavec
Keyword(s):  
North American ◽  
New Record ◽  
Current Knowledge ◽  
European Population ◽  
Separate Species ◽  
The North ◽  
Standing Waters ◽  
Relationship Of ◽  
European Form ◽  
American Form

The main objective of this study is to present a new record of Tasserkidrilus cf. americanus found in a channel near the Tešmak swamp in Slovakia (Central Europe) and to compare its morphological features and habitat requirements with those of populations occurring in North America and Europe. The new specimens are similar to those found in The Netherlands and Belgium, but dissimilar to previously reported North American material of T. americanus, reopening the question of whether the European form is a separate species. The European form has the penis sheaths approximately twice as long as and wider than the North American form and may inhabit slow-flowing or standing waters of a eutrophic character, which is in conflict with the current knowledge on the morphology and ecology of North American populations. Further investigation is necessary to solve the questions about the origin and taxonomic relationship of the European population to other populations.

Population structure of Heterobasidion annosum from North America and Europe

1993 ◽  
Vol 71 (8) ◽  
pp. 1064-1071 ◽  
Author(s):  
William J. Otrosina ◽  
Thomas E. Chase ◽  
Fields W. Cobb Jr. ◽  
Kari Korhonen
Keyword(s):  
Population Structure ◽  
North America ◽  
North American ◽  
Forest Tree ◽  
Heterobasidion Annosum ◽  
Evolutionary Relationships ◽  
The North ◽  
Isozyme Loci ◽  
Intersterility Groups ◽  
European Populations

Isolates of Heterobasidion annosum (Fr.) Bref. representing North American S and P and European S, P, and F intersterility groups were subjected to isozyme analysis. European S, P, and F groups had more variability than the North American S and P groups in expected hterozygosity, number of alleles per locus, and percent polymorphic loci. In contrast with the North American S and P groups, the European intersterility groups could not be distinguished from each other on the basis of individual isozyme loci, although significant differences in allele frequencies exist between European S and P groups. This suggests that evolution proceeded at different rates in the intersterility groups, or intersterility barriers appeared later in the European populations relative to the North American populations of H. annosum. Changes in climate and host species associations during the Tertiary may have been a major factor in evolution of H. annosum intersterility groups. Key words: allozymes, forest tree hosts, playnological events, evolutionary relationships, Hymenomycetes, root disease.

Allozyme variation in the Polygonum lapathifolium complex

1991 ◽  
Vol 69 (10) ◽  
pp. 2261-2270 ◽  
Author(s):  
Laurie L. Consaul ◽  
Suzanne I. Warwick ◽  
John McNeill
Keyword(s):  
North American ◽  
Taxonomic Status ◽  
Allozyme Variation ◽  
Genetic Distances ◽  
Allozyme Data ◽  
Separate Species ◽  
The North ◽  
Polygonum Lapathifolium ◽  
Polygonum Pensylvanicum ◽  
European Populations

The Polygonum lapathifolium complex consists of populations that are widely distributed in the Northern Hemisphere and that have been classified at different taxonomic levels. Allozyme data were used to test the current North American taxonomic status of members of the complex (including P. lapathifolium var. lapathifolium, P. lapathifolium var. salicifolium, and P. scabrum) and to verify diploidy in the P. lapathifolium complex and polyploid origins of the morphologically similar P. persicaria and P. pensylvanicum. Of the 15 enzyme systems surveyed in 50 populations of the complex, only 3 of the 23 loci (Acon, Lap, and Skdh) were polymorphic in the North American populations and a total of 6 loci in European populations. Fifteen multilocus genotypes were evident in the complex. Four genotypes (all with Lap-10.67 were exclusive to North American populations of P. lapathifolium, providing support for a North American element of the complex. Nine genotypes (all with Lap-10.63) were found in North American and European populations of P. scabrum, all European populations of the P. lapathifolium complex, and three populations of North American P. lapathifolium var. lapathifolium. Lap-10.67 was also found in the native tetraploid P. pensylvanicum, whereas Lap-10.63 was found in the introduced tetraploid P. persicaria. Genetic distances among populations did not support the current taxonomic divisions within the complex, nor did it support separate species status of P. scabrum. Allozyme data provided support for the allotetraploid origins of P. pensylvanicum and P. persicaria, with members of the P. lapathifolium complex as one of the parents of each. Key words: Polygonum lapathifolium, Polygonum scabrum, Polygonum pensylvanicum, Polygonum persicaria, allozymes.

scholarly journals PCR-RFLP markers identify three lineages of the North American and European populations ofPhytophthora ramorum

2009 ◽  
Vol 39 (4) ◽  
pp. 266-278 ◽  
Author(s):  
M. Elliott ◽  
G. Sumampong ◽  
A. Varga ◽  
S. F. Shamoun ◽  
D. James ◽  
...  
Keyword(s):  
North American ◽  
Rflp Markers ◽  
The North ◽  
Pcr Rflp ◽  
European Populations

Observations on the North American Form of Amphorophora rubi Kalt. (Homoptera, Aphididae)

1956 ◽  
Vol 88 (2) ◽  
pp. 89-91 ◽  
Author(s):  
Alex. R. Hill
Keyword(s):  
North America ◽  
Plant Breeding ◽  
North American ◽  
Rubus Idaeus ◽  
The North ◽  
Economic Significance ◽  
Breeding Programmes ◽  
American Form

In 1937 Schwarze and Huber (3) reported the variety of Rubus idaeus L named “Lloyd George” to be totally resistant to the aphid Amphorophora rubi Kalt. This fact was of some economic significance because the aphid in question had been shown to be an active vector of Rubus viruses in North America. It was suggested that the aphid-resistant qualities of Lloyd George should be incorporated in plant-breeding programmes with a view to producing hybrids, with desirable commercial qualities, which would escape infection by the viruses.

1588: The Bicalutamide Early Prostate Cancer Program: Findings of the North American Trial at 7.7 Years' Median Follow-Up

2006 ◽  
Vol 175 (4S) ◽  
pp. 511-512
Author(s):  
David G. McLeod ◽  
Ira Klimberg ◽  
Donald Gleason ◽  
Gerald Chodak ◽  
Thomas Morris ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
North American ◽  
Early Prostate Cancer ◽  
The North ◽  
Cancer Program
Sign in / Sign up

Export Citation Format

Share Document