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FRANCES K. KUPICHA F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1977,74(2):131-162
A survey of morphological, anatomical, karyological and chemical characters has been carried out, centred on the Vicieae but extending to the neighbouring tribes Trifolieae and Ononideae. The results show that Cicer , traditionally a member of the Vicieae, has more in common with genera of the Trifolieae and Ononideae than with the rest of the Vicieae. It is proposed that Cicer should be removed from the Vicieae and recognized as the monogeneric tribe Cicereae Alef. The tribe Vicieae sensu stricto, a well-defined natural group, is delimited and described. Phylogenetic relationships of the Cicereae are discussed. 相似文献
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Greylag Geese Anser anser have been neck-banded on an annual basis in Scania, southern Sweden since 1984 and in Norway since 1986 as part of a Nordic Greylag project. This has yielded a large database of resightings, which we used here to estimate and compare survival rates between the two populations by means of mark–recapture models. Estimated adult survival was sex-dependent in the Scanian population, probably a result of differential neck band retention rates in this population. Mean juvenile survival was about 12% higher in the Scanian population (0.603 vs. 0.485). Adult survival in the Norwegian population was 0.728 (males 0.733; females 0.725), and in males and females from the Scanian population was 0.711 (0.752 after accounting for higher neck band loss in males) and 0.771, respectively. Over the course of the study, juvenile survival in the Scanian population increased substantially, and adult survival was constant, whereas both these parameters declined in the Norwegian population. This study demonstrates that the two Nordic populations are demographically distinct and gives further support to the notion that they should be treated as separate management units. The decline of 10% in adult survival in the Norwegian population, the cause of which still remains uncertain, is likely to have had a major impact on the growth of this population. 相似文献
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FRANCES DENSMORE 《American anthropologist》1932,34(3):415-417
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Injection of Red Mexican bean leaves with Pseudomonas phascolicolaRace 2 (compatible, 18 h before P. mors-prunorum or P. phaseolicolaRace 1 (incompatible), or simultaneous inoculation with compatibleand incompatible bacteria (3:1) greatly delayed the appearanceof hypersensitive responses. When compatible bacteria were inoculated12 h or less before incompatible bacteria, or when the ratioof these bacteria was 1:1 or 0.3:1 in simultaneous inoculation,hypersensitive responses did develop. Earlier inoculation withincompatible bacteria delayed the appearance and severity ofdisease symptoms following later inoculation with compatiblebacteria. When selected areas of leaves were inoculated with compatiblebacteria, effects on hypersensitive responses were confinedto these areas when the whole leaf was inoculated later withincompatible bacteria. Inoculation through the upper leaf surfacewith incompatible bacteria did not affect susceptible responseswhen compatible bacteria were inoculated 24 h later throughthe lower surface. Treatment of leaves with heat-killed bacteria or live bacteriain numbers insufficient to cause hypersensitive responses didnot prevent development of these responses following later inoculationwith incompatible bacteria. Use of heat-killed bacteria didsuppress hypersensitive responses in tobacco leaves. Injectionof leaves with cycloheximide (20 p.p.m.) 30 min before inoculationwith incompatible bacteria suppressed leakage of electrolytesand browning of tissues associated with hypersensitive responses.Cycloheximide had little effect on leakage of electrolytes fromleaves inoculated with compatible bacteria or with the developmentof susceptible responses. Exposure of leaves to chloroform vapourdelayed hypersensitive responses by 24 h; treatment with peroxidasehad no effect. 相似文献
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Abstract: We investigated the dynamics of 8 populations of a bighorn sheep (Ovis canadensis) metapopulation in Hells Canyon, USA from 1997 to 2003. Pneumonia was the most common cause (43%) of adult mortality and the primary factor limiting population growth. Cougar (Puma concolor) predation was the second most-frequent source (27%) of adult mortality but did not reduce the rate of population growth significantly. Most pneumonia-caused mortality occurred in fall and early winter and most cougar predation occurred in late winter and early spring. Average annual survival of adult males (0.84) was lower than females (0.91). Pneumonia was the most common known cause of lamb mortality (86%), and pneumonia-related mortality was detected whenever summer lamb survival was <50%. Pneumonia-caused mortality rates in lambs were high from 21 days to 91 days of age and peaked at 42 days to 70 days. Summer pneumonia epizootics in lambs were independent of pneumonia-caused mortality in adults. Pneumonia-caused mortality occurred at the population level and was not synchronized geographically or temporally among populations. Although catastrophic all-age pneumonia-epizootics have previously been described in bighorn sheep, we found that chronic, although sporadic, pneumonia-caused mortality in adults and lambs can also have important effects on the dynamics of bighorn sheep populations. 相似文献