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Evaluation of Seed Storage Conditions and Genetic Diversity of Four Crucifers Endemic to Spain 总被引:1,自引:1,他引:0
Traditional assays (germination and vigour), as well as biochemicalassays using isozyme loci, were performed to evaluate the effectof different seed storage conditions in Coincya rupestris, Iberispectinata, Moricandia moricandiodes and Vella pseudocytisus.Seeds had been stored for 2430 years under long-term(LT) and short-term (ST) conditions. Fresh seeds of the samespecies from natural populations (NP) were also collected in1996 and used for comparison. Isozyme loci were used as markersof genetic deterioration and to determine the genetic diversityof samples. The germinability, vigour and enzyme activity ofLT samples were comparable to values obtained using freshlycollected NP samples, showing the effectiveness of the long-termstorage conditions. Copyright 1999 Annals of Botany Company Endemics, genetic diversity, germination, isozymes, seed ageing, seed storage, vigour. 相似文献
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JESSICA VROONEN BART VERVUST DOMENICO FULGIONE VALERIA MASELLI RAOUL VAN DAMME 《Biological journal of the Linnean Society. Linnean Society of London》2012,107(1):182-191
Colour has many different functions in animals, such as an involvement in thermoregulation, crypsis, and social interactions. Species capable of physiological colour change may alter their coloration in response to ecological conditions. The Moorish gecko, Tarentola mauritanica, is capable of actively changing its body coloration. In the present study, we investigated colour change in this gecko as a function of background, temperature, and light. Our results demonstrate that the Moorish gecko indeed changes its dorsal colour in response to changes in environmental conditions. By contrast to several other reptilian species, this rapid colour change does not appear to be associated with thermoregulation. Background matching, however, did appear to be a prominent function, although illumination appears to be an essential trigger. Future research should concentrate on individual variation and its effectiveness with respect to antipredatory mechanisms. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ?? , ??–??. 相似文献
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Human depopulation of rural mountain areas and the consequent abandonment of traditional land management are among the greatest driving forces behind changes in mountain ecosystems in Western Europe. Tree and shrub encroachment lead to an increase in landscape matrix uniformity and habitat fragmentation. For some animal species, this represents an unusual case of habitat loss caused by secondary succession. The animal species associated with this agro‐pastoral habitat may suffer from decreased connectivity as a consequence. The Rock Partridge Alectoris graeca is a species endemic to European mountains that represents a model for investigating the impact of habitat loss. We compared the habitat suitability of the Apennine Rock Partridge prior to abandonment of traditional agro‐pastoral activities by aerial photography with the current landscape, in order to investigate the effect of secondary succession on the distribution and viability of the species. We assessed the historical distribution (c. 1900–1950) by quantifying anecdotal evidence from interviews, and the current distribution (2005) from survey data. We applied ecological niche factor analysis and connectivity approaches to evaluate change in habitat suitability over this time scale. Moreover, to quantify landscape connectivity, we evaluated the relative importance of each patch in the two periods. Results indicated that to maintain a viable population in the Apennines, the species requires an ensemble of ecological conditions considerably different from the current situation. We observed a drastic decrease in connectivity as a result of a reduction in numbers and size of high suitability patches. This is most probably the primary cause of the current decline of the Rock Partridge population in the Apennines. 相似文献
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