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EL-Habib Dakir María-Luisa Ruiz Pedro García Marcelino Pérez de la Vega 《Genetic Resources and Crop Evolution》2002,49(6):619-631
The genetic variation existing in a set of barley (Hordeum vulgare L.) landrace samples recently collected in Morocco was estimated. Two kinds of genetic markers, seed storage proteins (hordeins) and random amplified polymorphic DNA (RAPD), were used. Only six out of 31 landraces were subjected to RAPD analysis. Both kinds of markers, RAPD and storage proteins, yielded similar results, showing that the level of variation observed in Moroccan barley was high: all landraces showed variability; 808 different storage protein patterns (multilocus associations) were observed among 1897 individuals (2.32 seeds per association, on average) with an average of 43 multilocus associations per accession. In general, genetic variation within accessions was higher than between accessions. The 100 polymorphic RAPD bands generated by 21 effective primers were able to generate enough patterns to differentiate between uniform cultivars and even between individuals in variable accessions. One of the aims of this work was to compare the effectiveness of RAPD versus storage protein techniques in assessing the variability of genetic resource collections. On average hordeins were more polymorphic than RAPDs: they showed more alternatives per band on gels and a higher percentage of polymorphic bands, although RAPDs supply a higher number of bands. Although RAPD is an easy and standard technique, storage protein analysis is technically easier, cheaper and needs less sophisticated equipment. Thus, when resources are a limiting factor and considering the cost of consumables and work time, seed storage proteins must be the technique of choice for a first estimation of genetic variation in plant genetic resource collections. 相似文献
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Collette BB Carpenter KE Polidoro BA Juan-Jordá MJ Boustany A Die DJ Elfes C Fox W Graves J Harrison LR McManus R Minte-Vera CV Nelson R Restrepo V Schratwieser J Sun CL Amorim A Brick Peres M Canales C Cardenas G Chang SK Chiang WC de Oliveira Leite N Harwell H Lessa R Fredou FL Oxenford HA Serra R Shao KT Sumaila R Wang SP Watson R Yáñez E 《Science (New York, N.Y.)》2011,333(6040):291-292
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Frederick T. Short Beth Polidoro Suzanne R. Livingstone Kent E. Carpenter Salomão Bandeira Japar Sidik Bujang Hilconida P. Calumpong Tim J.B. Carruthers Robert G. Coles William C. Dennison Paul L.A. Erftemeijer Miguel D. Fortes Aaren S. Freeman T.G. Jagtap Abu Hena M. Kamal Gary A. Kendrick W. Judson Kenworthy Yayu A. La Nafie Ichwan M. Nasution Robert J. Orth Anchana Prathep Jonnell C. Sanciangco Brigitta van Tussenbroek Sheila G. Vergara Michelle Waycott Joseph C. Zieman 《Biological conservation》2011,(7):1961-1971
Seagrasses, a functional group of marine flowering plants rooted in the world’s coastal oceans, support marine food webs and provide essential habitat for many coastal species, playing a critical role in the equilibrium of coastal ecosystems and human livelihoods. For the first time, the probability of extinction is determined for the world’s seagrass species under the Categories and Criteria of the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. Several studies have indicated that seagrass habitat is declining worldwide. Our focus is to determine the risk of extinction for individual seagrass species, a 4-year process involving seagrass experts internationally, compilation of data on species’ status, populations, and distribution, and review of the biology and ecology of each of the world’s seagrass species. Ten seagrass species are at elevated risk of extinction (14% of all seagrass species), with three species qualifying as Endangered. Seagrass species loss and degradation of seagrass biodiversity will have serious repercussions for marine biodiversity and the human populations that depend upon the resources and ecosystem services that seagrasses provide. 相似文献
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Patrícia A. B. Barreto Emanuela F. Gama-Rodrigues A. C. Gama-Rodrigues Alexandre G. Fontes José C. Polidoro Maria Kellen S. Moço Regina C. R. Machado V. C. Baligar 《Agroforestry Systems》2011,81(3):213-220
Agroforestry systems can play a major role in the sequestration of carbon (C) because of their higher input of organic material
to the soil. The importance of organic carbon to the physical, chemical, and biological aspects of soil quality is well recognized.
However, total organic carbon measurements might not be sensitive indicators of changes in soil quality. Adoption of procedures
that can extract the more labile fraction preferentially might be a more useful approach for the characterization of soil
organic carbon resulting from different soils. This study aimed to evaluate organic carbon (C) fractions distribution in different
soil layers up to 50 cm depth in two soil orders under cacao (Theobroma
cacao) agroforestry systems (AFS) in Bahia, Brazil. Soil samples were collected from four depth classes (0–5, 5–10, 10–30 and 30–50 cm)
under two cacao agroforestry systems (30-year-old stands of cacao with Erythrina glauca, as shade trees) in Latosol and Cambisol, in Bahia, Brazil. The determination of oxidizable carbon by a modified Walkley–Black
method was done to obtain four C fractions with different labile forms of C (fraction 1: labile fraction; fraction 2: moderate
labile fraction; fraction 3: low labile fraction and fraction 4: recalcitrant fraction). Overall, at two cacao AFS, the C
fractions generally declined with increase in soil depth. The C fractions 1 and 2 were 50% higher on upper layers (0–5 and
5–10 cm). More than 50% of organic C was found in more labile fraction (fraction 1) in all depths for both soils. High value
of C fraction 1 (more labile C)-to-total organic C ratio was obtained (around 54–59%, on Latosol and Cambisol, respectively),
indicating large input of organic matter in these soils. 相似文献
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Carpenter KE Abrar M Aeby G Aronson RB Banks S Bruckner A Chiriboga A Cortés J Delbeek JC Devantier L Edgar GJ Edwards AJ Fenner D Guzmán HM Hoeksema BW Hodgson G Johan O Licuanan WY Livingstone SR Lovell ER Moore JA Obura DO Ochavillo D Polidoro BA Precht WF Quibilan MC Reboton C Richards ZT Rogers AD Sanciangco J Sheppard A Sheppard C Smith J Stuart S Turak E Veron JE Wallace C Weil E Wood E 《Science (New York, N.Y.)》2008,321(5888):560-563
The conservation status of 845 zooxanthellate reef-building coral species was assessed by using International Union for Conservation of Nature Red List Criteria. Of the 704 species that could be assigned conservation status, 32.8% are in categories with elevated risk of extinction. Declines in abundance are associated with bleaching and diseases driven by elevated sea surface temperatures, with extinction risk further exacerbated by local-scale anthropogenic disturbances. The proportion of corals threatened with extinction has increased dramatically in recent decades and exceeds that of most terrestrial groups. The Caribbean has the largest proportion of corals in high extinction risk categories, whereas the Coral Triangle (western Pacific) has the highest proportion of species in all categories of elevated extinction risk. Our results emphasize the widespread plight of coral reefs and the urgent need to enact conservation measures. 相似文献
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The status of marine biodiversity in the Eastern Central Atlantic (West and Central Africa) 
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下载免费PDF全文 Beth A. Polidoro Gina M. Ralph Kyle Strongin Michael Harvey Kent E. Carpenter Rachel Arnold Jack R. Buchanan Khairdine Mohamed Abdallahi Camara Bruce B. Collette Mia T. Comeros‐Raynal Godefroy De Bruyne Ofer Gon Antony S. Harold Heather Harwell Percival A. Hulley Tomio Iwamoto Steen W. Knudsen Jean de Dieu Lewembe Christi Linardich Kenyon C. Lindeman Vanda Monteiro Thomas Munroe Francis K.E. Nunoo Caroline M. Pollock Stuart Poss Barry Russell Catherine Sayer Aboubacar Sidibe William Smith‐Vaniz Emilie Stump Mor Sylla Luis Tito De Morais Jean‐Christophe Vié Akanbi Williams 《水产资源保护:海洋与淡水生态系统》2017,27(5):1021-1034
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S. Alcantara D.V. Pérez M. R. A. Almeida G.M. Silva J.C. Polidoro W. Bettiol 《Water, air, and soil pollution》2009,203(1-4):3-16
The need for solutions to minimize the negative environmental impacts of anthropogenic activities Fhas increased. Sewage sludge is composed of predominantly organic matter and can be used to improve soil characteristics, such as fertility. Therefore, its application in agriculture is an adequate alternative for its final disposal. However, there is a lack of information on its long-term effects on soil changes in tropical areas. Thus, the objectives of this study were to determine (i) the effect of sewage sludge application on heavy metal build-up in soil and maize grains and leaves, and (ii) the effects of soil amendment with sewage sludge on the chemical properties of a Brazilian oxisol. Besides the increasing levels of Zn, Cu, Ni, and Cr, amending soil with sewage sludge also alters the distribution of these metals by increasing the mobile Phases, which correlated significantly with the increase in metal extraction with two single extractants, Mehlich 1 and DTPA (Diethylene triamine pentaacetic acid). The levels of Fe, Mn, Zn, and Cu in maize grains and leaves increased with the type and rate of sewage sludge application. Nevertheless, metal build-up in soil and plants was within the allowed limits. Significant differences were also found in soil characteristics like humic fractionation with the applied sewage doses. The data obtained does not indicate any expressive drawbacks in the use of sewage sludge as a soil amendment, as the heavy metal concentrations observed are unlikely to cause any environmental or health problems, even overestimated loadings, and are in accordance with the Brazilian regulations on farming land biosolid disposal. 相似文献
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