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71.
72.
Dominique Frechon Pascale Exbrayat Valerie Helias Lizbeth J. Hyman B. Jouan P. Llop Maria M. Lopez Nicole Payet M. C. M. Pérombelon I. K. Toth José R. C. M. van Beckhoven J. M. van der Wolf Y. Bertheau 《Potato Research》1998,41(2):163-173
Summary A PCR-based kit, ProbeliaTM, for the detection ofErwinia carotovora subsp.atroseptica (Eca) on potatoes was evaluated at five laboratories in four countries. The kit is based on DNA-specific PCR amplification
followed by detection of amplicons by hybridization to a peroxidase-labelled DNA probe in a microplate. Specificity of the
PCR primers for Eca, regardless of serogroups, was confirmed by testing against 246 bacterial, fungal and plant species. Detection
limits of the assay varied little between six Eca strains in pure cultures (1.3×102 to 1.5×103 cells ml−1). When Eca-free tuber peel extract from four cultivars was inoculated with known numbers of 15 Eca strains, detection limits
were more variable (1.0×101 to 6.2×103 cells ml−1 peel extract), attributed probably to inconsistency in the recovery of DNA during extraction. When the PCR assay was compared
with three current commercial Eca detection methods, using naturally contaminated tubers, results matched most closely those
from viable counts on a selective medium, the most sensitive method (88%), followed by enrichment ELISA (72%) and last ELISA
(30%), the least sensitive method. 相似文献
73.
Erwann Lagabrielle Mathieu Rouget Karine Payet Nokuthula Wistebaar Laurent Durieux Amanda Lombard 《Biological conservation》2009,142(7):1523-130
Over the last century, island biodiversity has become one of the most threatened in the world. Although many island conservation plans address biodiversity requirements at the species level, few plans address the spatial requirements of the biodiversity processes that underpin the persistence of these species. Using systematic conservation planning principles, we map the spatial components of biodiversity processes (SCBPs) and use these to design broad-scale conservation corridors for Réunion Island. Our method is based upon a literature review, expert knowledge, spatially explicit base data, conservation planning software, and spatial modelling. We combine a target-driven algorithm with least-cost path analyses to delineate optimal corridors for capturing key biodiversity processes while simultaneously considering biodiversity pattern targets, conservation opportunities, and future threats. We identify five SCBPs: the oceanic-terrestrial interface; riverine corridors; macrohabitat interfaces; the boundaries of isolated topographic units; and lowland-upland gradients. A large proportion of the SCBPs (81.3%) is currently untransformed, whereas 3% is irreversibly transformed by urbanisation and 15.7% is transformed but restorable. However, SCBPs are almost fully disrupted by urbanisation in the lowlands, thereby compromising functional corridors along full altitudinal gradients. This study is a contribution toward the reconciliation of conservation versus development objectives on Réunion Island but we believe that the delineation method is sufficiently general to be applied to other islands. Our results highlight the need for integrating marine, coastal and terrestrial conservation planning as a matter of urgency, given the rapid transformation of coastal areas on islands. 相似文献
74.
Guginski-Piva Claudia Aparecida Bogo Amauri Gomes Beatriz Ribeiro Menon Jessica Karine Nodari Rubens Onofre Welter Leocir José 《植物病害和植物保护杂志》2018,125(4):405-413
Journal of Plant Diseases and Protection - Recent review described that grape anthracnose in Brazil is caused by Elsinoe ampelina. However, in many countries, anthracnose can be associated with... 相似文献
75.
Nagai S Dubrana K Tsai-Pflugfelder M Davidson MB Roberts TM Brown GW Varela E Hediger F Gasser SM Krogan NJ 《Science (New York, N.Y.)》2008,322(5901):597-602
Recent findings suggest important roles for nuclear organization in gene expression. In contrast, little is known about how nuclear organization contributes to genome stability. Epistasis analysis (E-MAP) using DNA repair factors in yeast indicated a functional relationship between a nuclear pore subcomplex and Slx5/Slx8, a small ubiquitin-like modifier (SUMO)-dependent ubiquitin ligase, which we show physically interact. Real-time imaging and chromatin immunoprecipitation confirmed stable recruitment of damaged DNA to nuclear pores. Relocation required the Nup84 complex and Mec1/Tel1 kinases. Spontaneous gene conversion can be enhanced in a Slx8- and Nup84-dependent manner by tethering donor sites at the nuclear periphery. This suggests that strand breaks are shunted to nuclear pores for a repair pathway controlled by a conserved SUMO-dependent E3 ligase. 相似文献
76.
Le Roch KG Zhou Y Blair PL Grainger M Moch JK Haynes JD De La Vega P Holder AA Batalov S Carucci DJ Winzeler EA 《Science (New York, N.Y.)》2003,301(5639):1503-1508
The completion of the genome sequence for Plasmodium falciparum, the species responsible for most malaria human deaths, has the potential to reveal hundreds of new drug targets and proteins involved in pathogenesis. However, only approximately 35% of the genes code for proteins with an identifiable function. The absence of routine genetic tools for studying Plasmodium parasites suggests that this number is unlikely to change quickly if conventional serial methods are used to characterize encoded proteins. Here, we use a high-density oligonucleotide array to generate expression profiles of human and mosquito stages of the malaria parasite's life cycle. Genes with highly correlated levels and temporal patterns of expression were often involved in similar functions or cellular processes. 相似文献
77.
Volkman SK Hartl DL Wirth DF Nielsen KM Choi M Batalov S Zhou Y Plouffe D Le Roch KG Abagyan R Winzeler EA 《Science (New York, N.Y.)》2002,298(5591):216-218
The detection of single-nucleotide polymorphisms in pathogenic microorganisms has normally been carried out by trial and error. Here we show that DNA hybridization with high-density oligonucleotide arrays provides rapid and convenient detection of single-nucleotide polymorphisms in Plasmodium falciparum, despite its exceptionally high adenine-thymine (AT) content (82%). A disproportionate number of polymorphisms are found in genes encoding proteins associated with the cell membrane. These genes are targets for only 22% of the oligonucleotide probes but account for 69% of the polymorphisms. Genetic variation is also enriched in subtelomeric regions, which account for 22% of the chromosome but 76% of the polymorphisms. 相似文献
78.
79.
The Black Sea is a semi-enclosed body of water that differs from the adjacent Mediterranean Sea in terms of its biodiversity, oceanographical and ecological characteristics. There is growing international concern about pollution in the Black Sea and other anthropogenic threats to its fauna. The bottlenose dolphin (Tursiops truncatus) is one of three species of cetaceans living in the Azov-Black Sea basin. Despite considerable research on bottlenose dolphins elsewhere, the extent of human impacts on the Black Sea populations is unknown. Previous attempts to award special conservation status to Black Sea cetaceans have failed specifically because policy makers have viewed their ecological and evolutionary uniqueness as equivocal. This study assessed divergence between Black Sea, Mediterranean Sea and Atlantic Ocean bottlenose dolphins for 26 cranial measurements (n = 75 adult bottlenose dolphin skulls) and mitochondrial DNA (n = 99 individuals). Black Sea bottlenose dolphins are smaller than those in the Mediterranean, and possess a uniquely shaped skull. As in a previous study, we found the Black Sea population to be genetically distinct, with relatively low levels of mtDNA diversity. Population genetic models suggest that Black Sea bottlenose dolphins have so little gene flow with the Mediterranean due to historical isolation that they should be managed separately. 相似文献
80.
Forest pasturing of free-roaming livestock is a common practice in many parts of the world, but knowledge on how it affects tree regeneration in boreal forests is lacking. We mapped tree density, livestock site use and accumulated damage to young trees of commercial interest(Norway spruce, Picea abies L. Karst.) on 56 clearcuts inside and outside a fenced forest area used for livestock pasturing in Ringsaker, Norway. Inside the fence 56±1.8% of spruce trees were damaged compared to 37±3.4% outside. Proportion of damaged spruce trees was positively related to cattle use of the clearcut, but not so for sheep. On the most intensively used clearcuts, four out of five trees were damaged. The density of deciduous trees was five times lower inside compared to outside of the fence(varying with plant species). While livestock grazing may reduce resource competition in favour of spruce, the current animal density clearly is impeding forest regeneration in the study area. 相似文献