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We describe primers and polymerase chain reaction (PCR) conditions to amplify 18 tetranucleotide microsatellite DNA loci in eastern bluebirds (Sialia sialis). The primers were tested using individuals from two study sites in Georgia and South Carolina. Among individuals from the Georgia population (n = 23), the primer pairs developed in this study yielded an average of 6.6 alleles per locus (range 2–12), an average observed heterozygosity of 0.56 (range 0.24–0.96) and an average polymorphic information content of 0.65 (range 0.3–0.86). Among individuals from the South Carolina population (n = 19), the primer pairs yielded an average of 5.8 alleles per locus (range 2–9), an average observed heterozygosity of 0.56 (range 0.05–0.86) and an average polymorphic information content of 0.63 (range 0.29–0.83).  相似文献   
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The nine Siberian species described by Stuxberg in the genus Lithobius are redescribed from the original material. It is concluded that six of these species (ostiacorum, princeps, sulcipes, nordenskioldii, fugax and vagabundus) are valid and that three (scrobiculatus, formicarum and captivus) are junior synonyms. Three further species, one of them new, have been found among Stuxberg's Siberian specimens and are described.  相似文献   
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J. S. BUNIN  I. G. JAMIESON  D. EASON 《Ibis》1997,139(1):144-151
Many of New Zealand's endangered birds have been transferred from the “mainland” of the North and South Islands to smaller coastal islands free from introduced predators and competitors. The transfer of Takahe Porphyrio mantelli (Plate 1) to offshore islands is unique because these highly endangered, flightless rails are being moved from alpine-tussock habitat of Fiordland, the last remaining natural population, to substantially different lowland habitat on island refuges. Despite the fact that 30% of the approximately 160 Takahe left in the wild now live on coastal islands, a detailed analysis on the success of the island populations has never been undertaken. Using data available from New Zealand's Department of Conservation, we found that while adult survivorship of Takahe on islands is high, reproductive success is significantly lower than in Fiordland. Most factors examined, including inbreeding and nutrient deficiency, had no significant effect on reproductive success of Takahe breeding on islands. Island pairs produced fewer eggs and juveniles in the first year of their pair bond relative to all other years. Hence the large number of transfers of birds between islands during the initial stages of the relocation program may have resulted in a higher frequency of pair formation and thus may have contributed to the islands' lower reproductive success. Why first clutches did so poorly (four juveniles from 43 clutches) compared with second (11 from 36) and third (six from 13) clutches is not known but was one of the main contributing factors for island pairs making greater nesting effort but significantly lower returns than birds breeding in Fiordland. In addition, some individual birds have been very successful in producing young relative to other birds, suggesting that important differences in quality of some breeders may also exist. We expect island productivity will improve over time as the number of interisland transfers of Takahe decreases and as the proportion of breeding birds raised in the island environment increases.  相似文献   
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The status of the 15 European and Mediterranean species and subspecies of Lithobiidae described by Verhoeff which are represented by material in the Verhoeff Collection of Myriapoda in the British Museum (Natural History) is evaluated. It is concluded that Lithobius fasciatus graecus is a junior synonym of Eupolybothrus litoralis (L. Koch), Polybothrus cerberus brentanus a junior synonym of Eupolybothrus tridentinus (Fanzago) and Lithobius pachypus a junior synonym of Hessebius barbipes (Porat); Lithobius corcyraeus and Lithobius forjicatus calamatanus are both junior synonyms of Lithobius viriatus Sseliwanoff; Lithobius pusillus var. parvus and Lithobius audax jaqueti are both junior synonyms of, and Lithobius borisi a subspecies of, Lithobius erythrocephalus C. L. Koch; Lithobius leostygis and Lithobius herzegowinensis are both valid species of Eupolybothrus Verhoeff; and Lithobius forjicatus parietum, Lithobius erythrocephalus cerberi, Lithobius acuminatus cassinensis and Lithobius trebinjanus are all valid species of Lithobius Leach. The status of Lithobius vosseleri is still undecided. The specimens of all but the well-known species are fully described and, where appropriate, lectotypes are selected.  相似文献   
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Phillips, R., Press, M. C. and Eason, A. 1987. Polyamines inrelation to cell division and xylogenesis in cultured explantsof Helianthus tuberosus: lack of evidence for growth-regulatoryaction.—J. exp. Bot. 38: 164–172. The polyamines spermidine, diaminopropane, and cadaverine werefound to accumulate in cultured tuber explants of H. tuberosus(Jerusalem artichoke). Rapid increases in all amines occurredduring the initial 24 h corresponding to the period of activationand the onset of mitosis. Levels then declined during the followingphases of rapid cell proliferation and xylem differentiation.The type and distribution of polyamines was not markedly affectedby changes in medium or culture conditions, and the inhibitorMGBG did not alter cell division rates or polyamine contentmarkedly although xylem differentiation was substantially depressed.Exogenously supplied spermidine and putrescine did not substantiallyalter the cellular responses of explants cultured in the presenceof auxin. In the absence of supplied auxin, spermidine at 1?0mol m–3 produced an increase in cell division, althoughthis was small in comparison with auxin-stimulated responses.The implications of these findings on the possibility that polyaminesact as growth regulators in plants is discussed. Key words: Polyamines, Jerusalem artichoke, cultured explants, cell division, xylem differentiation  相似文献   
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The 32 species described by Meinert in the genus Lithobius which are represented by type material in t h e Zoological Museum, Copenhagen University, are redescribed from that material. It is concluded that 17 of these species are valid, one is a subspecies of Lithobius forficants (L.) and 12 are junior synonyms: two are junior homonyms, but both are also synonyms of described species.  相似文献   
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