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41.
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LINDA M. McINNES IAN R. DADOUR MEREDITH E. STEWART WILLIAM G. F. DITCHAM PETER MAWSON PETER B. S. SPENCER 《Molecular ecology resources》2005,5(3):504-506
Microsatellite loci were isolated from Carnaby's black cockatoo (Calyptorhynchus latirostris: Aves), a highly valued, endangered, and endemic species of bird from Western Australia. This study describes three dinucleotide and one tetranucleotide microsatellite loci for which the primers produced clear and polymorphic amplification patterns with between two and nine alleles and moderate levels of variability. Two additional dinucleotide markers which were monomorphic in the Carnaby's cockatoo were able to amplify and were polymorphic in two other species of black cockatoo, greatly increasing the utility of these markers. 相似文献
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A bacterial clone carrying sequences coding for elongation factor EF-1 alpha from Artemia 总被引:2,自引:0,他引:2
A bacterial cDNA clone was identified carrying one third of the nucleotides coding for elongation factor EF-1 alpha from the brine shrimp Artemia. The sequence of codons corresponds with the known sequence of amino acids of EF-1 alpha in the region involved. 相似文献
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An examination of four species of Cirsium disclosed the presence of two new flavonoids in C. lineare. The structure of one was 5,4′-dihydroxy-6,7,3′-trimethoxyflavone (cirsilineol) 4′-monoglucoside and the other 5,3′,4′-trihydroxy-6,7-dimethoxyflavone (cirsiliol) 4′-monoglucoside. Luteolin 7-glucoside was found in C. suffultum, and pectolinarin and linarin in C. kamtschaticum and C. pectinellum. 相似文献
47.
M. A. PEIRCE 《The Journal of eukaryotic microbiology》1973,20(5):543-546
An avian piroplasm, Nuttallia balearicae sp. n., is described from captive Balearica p. pavonina and B. p. gibbericeps. Other avian piroplasms and their validity and taxonomic status are discussed. The possible route of transmission of these parasites is also considered. 相似文献
48.
J. Stephen Brewer 《应用植被学》2006,9(1):11-16
Question: What are the mechanisms by which fire reduces competition for both a short‐lived and a long‐lived species in old‐growth ground‐cover plant communities of wet pine savannas (originally Pinus palustris, replaced by P. elliottii)? Location: Outer coastal plain of southeastern Mississippi, USA. Methods: I reviewed previous competition experiments and proposed a new hypothesis to explain the relationship between fire, competition, and species co‐existence in wet longleaf pine savannas. The first study is about growth and seedling emergence responses of a short‐lived carnivorous plant, Drosera capillaris, to reduction in below‐ground competition and above‐ plus below‐ground competition. The second study deals with growth and survival responses of a long‐lived perennial carnivorous plant, Sarracenia alata, to neighbour removal and prey‐exclusion to determine if a reduction in nutrient supply increased the intensity of competition in this nutrient‐poor system. Results: Fire increased seedling emergence of the short‐lived species by reducing above‐ground competition through the destruction of above‐ground parts of plants and the combustion of associated litter. Prey exclusion did not increase competitive effects of neighbours on the long‐lived species. However, because the experiment was conducted in a year without fire, shade reduced nutrient demand, which may have obviated competition for soil nutrients between Sarracenia alata and its neighbours. Conclusion: Repeated fires likely interact with interspecific differences in nutrient uptake to simultaneously reduce both above‐ground competition and competition for nutrients in old‐growth ground cover communities in pine savannas. Restoration practitioners should consider the possibility that the composition of the plant community is just as important as fire in ensuring that frequent fires maintain species diversity. 相似文献
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Trap sampling over reefs in deep (mean = 20 m) and shallow (mean = 10 m) waters along c. 1500 km of coastline in tropical north‐western Australia during both day and night and in wet and dry periods yielded 23 377 fishes, representing 32 families, 58 genera and 119 species. Individuals of the Serranidae, Lutjanidae, Lethrinidae and Carangidae contributed 88·9% to the total catch. The ichthyofaunal compositions of the Kimberley, Canning and Pilbara bioregions were relatively discrete. Species composition was influenced far more by location (latitude) than by water depth, period and time of day, and underwent a gradational change southwards. The latter change reflected differences in the trends exhibited by the relative abundances of certain species with increasing latitude and the confinement of other species largely to particular regions. The three most abundant species, i.e. Lethrinus sp. 3, Lutjanus carponotatus and Lethrinus laticaudis contributed 34·8, 20·8 and 11·6% to the total catch, respectively. The first species was rarely recorded in the two most northern locations and was abundant in the four most southern locations, whereas the last two species were relatively more abundant in northern than in southern locations. Lutjanus bitaeniatus and Lutjanus johnii were found exclusively at the two locations in the Kimberley region, whereas Abalistes stellatus, Pentapodus emeryii and Lethrinus nebulosus were not caught in this region but were found in both locations of the Canning and Pilbara regions. The species composition in deep and shallow waters at each location almost invariably differed significantly between day and night and between dry and wet periods, with species such as L. bitaeniatus, L. johnii, Lutjanus sebae and A. stellatus being more abundant over deep reefs, whereas L. carponotatus, L. laticaudis, Siganus fuscescens and Lethrinus lentjan were more numerous over shallow reefs. Species such as L. johnii and Lethrinus atkinsoni were relatively more important in night‐time than daytime catches, whereas the reverse applied to Lethrinus lentjan, L. laticaudis and Choerodon cyanodus. Lethrinus sp. 3 and L. laticaudis were relatively more important in catches during the dry than wet period. 相似文献
50.
Sensitivity to and requirement for iron in Plantago species 总被引:1,自引:0,他引:1