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A. Pérez-Sierra P. Romón-Ochoa C. Gorton A. Lewis H. Rees S. Van Der Linde J. Webber 《Plant pathology》2019,68(4):727-737
Chestnut blight, caused by Cryphonectria parasitica, was identified in Devon, UK, in December 2016. Intensive surveys detected the disease at further sites in Devon (seven), Berkshire (one), Dorset (one), Derbyshire (four) and a cluster of eight sites in southeast London. Over 570 survey samples were tested, and 227 were positive for C. parasitica by isolation and real-time PCR. A total of 227 isolates were tested for mating type, and 197 screened for vegetative compatibility group (VCG) and compared with VCGs known from mainland Europe. The same isolates were also screened for the presence of Cryphonectria hypovirus 1 (CHV-1). Eleven VCGs were identified within the UK population. Five corresponded to already known European VCGs but six were unique. The European VCGs mainly came from the Devon, Dorset, Berkshire and Derbyshire disease outbreaks, whilst unique VCGs were almost exclusively from the southeast London cluster. Both mating types were detected, but only one mating type was present at each site, with the exception of a single Devon site. Perithecia of C. parasitica were never observed at any site. CHV-1 was found in seven isolates from three different locations and was always subtype-I, which has limited hypovirulence. Therefore, although CHV-1 is associated with C. parasitica at some outbreaks, it probably has limited impact on virulence. The diversity of VCGs and their distribution at outbreak sites, together with findings of CHV-1, suggests C. parasitica has been introduced to the UK multiple times over at least two decades through international plant trade. 相似文献
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Snyder Marcía N. Schumaker Nathan H. Ebersole Joseph L. Dunham Jason B. Comeleo Randy L. Keefer Matthew L. Leinenbach Peter Brookes Allen Cope Ben Wu Jennifer Palmer John Keenan Druscilla 《Landscape Ecology》2019,34(5):1197-1197
Landscape Ecology - In the original publication of the article, the third author name has been misspelt. The correct name is given in this Correction. The original version of this article was revised. 相似文献
5.
Morantes César Fernández Yarza Florencia Montes María L. Mercader Roberto C. Curutchet Gustavo Torres Sánchez Rosa M. 《Water, air, and soil pollution》2020,231(1):1-13
Water, Air, & Soil Pollution - The treatment efficiency of Chlorella sorokiniana and Scenedesmus species, immobilized in sodium alginate, was evaluated for removing nitrate from groundwater.... 相似文献
6.
da Silva Isadora Gonçalves Castoldi Renata de Oliveira Charlo Hamilton César de Souza Miranda Mateus Nunes Thaíssa Dias Cardoso Costa Luciene Lacerda Lemes Ernane Miranda 《Journal of Crop Science and Biotechnology》2020,23(2):191-196
Journal of Crop Science and Biotechnology - The cultivation of sweet corn is expanding in Brazil, but there are serious constraints about the availability of commercial cultivars. The selection of... 相似文献
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Mattana Efisio Peguero Brígido Di Sacco Alice Agramonte Wilvin Encarnación Castillo Wilkin Rafael Jiménez Francisco Clase Teodoro Pritchard Hugh W. Gómez-Barreiro Pablo Castillo-Lorenzo Elena Terrero Encarnación Marianny Way Michael J. García Ricardo Ulian Tiziana 《New Forests》2020,51(4):705-721
New Forests - Native trees from the Caribbean were tested for seed desiccation responses, by adapting the “100-seed test” protocol. Ninety-seven seed lots of 91 species were collected... 相似文献
8.
Stable isotopes and gut contents indicate differential resource use by coexisting asp (Leuciscus aspius) and pikeperch (Sander lucioperca) 下载免费PDF全文
Mojmír Vašek Antti P. Eloranta Ivana Vejříková Petr Blabolil Milan Říha Tomáš Jůza Marek Šmejkal Josef Matěna Jan Kubečka Jiří Peterka 《Ecology of Freshwater Fish》2018,27(4):1054-1065
Differential use of habitat and prey resources is an important mechanism that may allow coexistence of sympatric species. Unlike interactions between smaller cyprinid and percid fishes, the resource use by coexisting predatory asp (Leuciscus aspius) and pikeperch (Sander lucioperca) is relatively unknown. Here, gut content and stable isotope analyses were used to study ontogenetic dietary shifts and interspecific trophic niche overlap between asp and pikeperch coexisting in two reservoirs. The hypothesis that both species show an ontogenetic dietary shift from small invertebrates to large fish prey, but at the same time use different prey resources to reduce potential competitive interactions, was validated. The isotopic niches of the two predators showed no, or only a moderate, degree of overlap (0%–65%). The ontogenetic changes in the degree of interspecific isotopic niche overlap were different in the two reservoirs, suggesting that trophic segregation can be dynamic and variable among systems. Gut contents revealed that small (<100 mm standard length) asp consumed mostly terrestrial invertebrates and emerged aquatic insects, whereas small pikeperch foraged on zooplankton, larval and pupal stages of aquatic insects and fish. Larger individuals (>100 mm) of both species were predominantly piscivorous, with asp consuming more cyprinid prey and pikeperch more percid prey. Coexisting asp and pikeperch populations are able to utilise different prey resources, thereby reducing potential negative competitive interactions. 相似文献
9.
Does full protection count for the maintenance of β‐diversity patterns in marine communities? Evidence from Mediterranean fish assemblages 下载免费PDF全文
Luca Appolloni Stanislao Bevilacqua Luisa Sbrescia Roberto Sandulli Antonio Terlizzi Giovanni Fulvio Russo 《水产资源保护:海洋与淡水生态系统》2017,27(4):828-838
- Although it is widely recognized that protection may enhance size, abundance, and diversity of fish, its effect on spatial heterogeneity of fish assemblages and species turnover is still poorly understood.
- Here the effect of full protection within a Mediterranean marine protected area on β‐diversity patterns of fish assemblages along a depth gradient comparing a no‐take zone with multiple unprotected areas is explored. The no‐take zone showed significantly higher synecological parameters, higher β‐diversity among depths, and lower small‐scale heterogeneity of fish assemblages relative to unprotected areas.
- Such patterns might likely depend on the high level of fishing pressure outside the no‐take zone, as also abundance‐biomass curves seemed to indicate. Results suggested that full protection could play a role in maintaining high β‐diversity, thus reducing the fragility of marine communities and ecosystems, and spatial heterogeneity may represent a reliable predictor of how management actions could provide insurance against undesirable phase shifts.
10.
Effect of dietary protein content on growth rate,survival and body composition of juvenile cauque river prawn,Macrobrachium americanum (Bate 1868) 下载免费PDF全文
Yuniel Méndez‐Martínez Stig Yamasaki‐Granados Marcelo U García‐Guerrero Luis R Martínez‐Córdova Marta E Rivas‐Vega Fabiola G Arcos‐Ortega Edilmar Cortés‐Jacinto 《Aquaculture Research》2017,48(3):741-751
We determined the effect of four concentrations of dietary crude protein, 30.7, 37.2, 41.8 and 46.8% on growth rate, survival and body composition of the juvenile cauque river prawn (Macrobrachium americanum). The prawns were hatched in the laboratory from the spawn of one wild ovigerous female. Prawns consuming 37.2% crude protein reached a final weight of 0.58 g (feed conversion ratio of 2.15), which was significantly better than the other treatments. Survival was 100% in all treatments. Protein content in the diets had no significant effect on whole body proximate composition and amino acid profile. Juveniles consuming the 37.2% crude protein diet grew faster than those fed the other diets. Specific growth rate was adjusted to the two‐slope broken‐line regression analysis model to estimate the optimal protein requirement. In conclusion, these results demonstrated that the 37.2% protein level diet is optimal for juvenile cauque river prawn M. americanum in the experimental conditions of this study. 相似文献