Search

A sample of 1107 fish served to age and to analyze growth of European conger eel (Conger conger) from NE Atlantic Ocean using otoliths and vertebrae.

Twenty-six isolates obtained from soybean crops (Glycine max) with typical anthracnose symptoms were identified as Colletotrichum truncatum (73 %) and C. destructivum (26 %). Their genetic relationships were studied using the AFLP method. A UPGMA phenogram divided the strains into two clusters corresponding with the two species. Genetic distances based on association coefficient were 0.71-0.89 among the 18 C. truncatum strains and 0.67-1 among the eight C. destructivum strains. Genetic variability within species, measured in terms of percentage of polymorphic loci, was high (

The objectives of this study were to develop breed-specific single nucleotide polymorphisms (SNPs) in five pig breeds sequenced with Illumina's Genome Analyzer and to investigate their usefulness for breed assignment purposes. DNA pools were prepared for Duroc, Landrace, Large White, Pietrain and Wild Boar. The total number of animals used for sequencing was 153. SNP discovery was performed by aligning the filtered reads against Build 7 of the pig genome. A total of 313,964 high confidence SNPs were identified and analysed for the presence of breed-specific SNPs (defined in this context as SNPs for which one of the alleles was detected in only one breed). There were 29,146 putative breed-specific SNPs identified, of which 4441 were included in the PorcineSNP60 beadchip. Upon re-examining the genotypes obtained using the beadchip, 193 SNPs were confirmed as being breed specific. These 193 SNPs were subsequently used to assign an additional 490 individuals from the same breeds, using the sequenced individuals as reference populations. In total, four breed assignment tests were performed. Results showed that for all methods tested 99% of the animals were correctly assigned, with an average probability of assignment of at least 99.2%, indicating the high utility of breed-specific markers for breed assignment and traceability. This study provides a blueprint for the way next-generation sequencing technologies can be used for the identification of breed-specific SNPs, as well as evidence that these SNPs may be a powerful tool for breed assignment and traceability of animal products to their breeds of origin.

Simpósio Nacional de Olivicultura, 5º, Santarém, 24-26 de Setembro, 2009 Phenological development of the olive tree is important for studying its adaptability, for management and simulation of growth and yield of olive orchards. Nevertheless, most studies that predict the date of flowering of the olive do not consider its chilling requirements, that are low, but may not be satisfied in some years, under mild climates or when global warming takes effect. In a previous study De Melo-Abreu et al. (2004) a model designed to predict the date of flowering was presented along with appropriate parameters for some cultivars. It is a two phase model. In the first phase, chilling accumulation takes place using a four parameter sub-model for determination of chilling units. In the second phase, known as the forcing phase, that starts after chilling requirements were attained and bud-break was due to occur, temperature sum above a base temperature is used to simulate development. Furthermore, it was established that all the parameters for the chilling accumulation, except the required chilling units, are conservative for all cultivars that were studied. A custom-tailored algorithm was constructed for the determination of the total sum of chilling units for bud-break and for the temperature sum necessary for the forcing phase. The resulting calibrated model is used for the prediction of the impact of global warming in the dates of flowering of the olive trees ‘Arbequina’, ‘Gordal’, ‘Hojiblanca’, ‘Manzanilla’, ‘Moraiolo’, ‘Picual’ and ‘Verdial’ for the four locations that are representative of the main olive producing regions in Portugal. The present climate is represented by a series of 19 and 30 years of maximum and minimum daily temperatures (Cen0). Three scenarios of climate change were considered. Cen1, Cen2 and Cen3 correspond, respectively, to increases of 1°C, 2°C and 3°C to both maximum and minimum temperaturesIn Vila Real, projections indicate successive advances in the date of flowering, from 11 to 12 days in Cen1 until 33 to 37 days in Cen3. In Castelo Branco, the projections indicate advances of flowering date from 11 to 13 days in Cen1 until 23 to 36 days in Cen3. In both locations, no faulty of abnormal flowering were anticipated. In Beja, the o projections indicate that advances in the date of flowering for Cen1 and Cen2 are modest, that ‘Moraiolo’ has a single event of faulty or abnormal flowering in Cen2 and that all cultivars that were studied have years with faulty or abnormal flowerings in Cen3. In Faro, important delays in the date of flowering were anticipated in all scenarios, and in many years flowering is absent or abnormal. In Cen3, the projections indicate that flowering is likely to be absent or abnormal in almost all years. The results that were obtained are an indication that may help the farmer to include or reject cultivars in future olive orchards.

Pedosedimentary processes, recorded in a late Quaternary section near Zarate city, north Buenos Aires province are reconstructed in this study. Both field features and laboratory results were analyzed as a whole. Grain size, sand, silt and clay mineralogy, micromorphology, Rb and Sr concentrations, optical stimulated luminescence (OSL) ages as well as preliminary paleomagnetic analysis were performed in order to get a detailed information on processes involved. All studied paleosols were developed on loess horizons. Four definite breaks in sedimentation and a coupled development of paleosols were observed. On this basis four units showing different types of calcretes were defined. Welded paleosols at unit C, could be correlated to those studied at Baradero (Buenos Aires province) and Lozada (Córdoba province), which probably record the last interglacial stage before present, the Marine Isotopic Stage 5 (MIS5), studied on marine cores. The highest values of Rb/Sr ratio reflect changes due to chemical weathering processes and generally match paleosol levels occurrences. Development of ground water-related and pedogenic calcretes, as well as their association to smectite, illite and ferric oxide indicate drier weather conditions than present and strong seasonality. Finally, a tentative correlation between one of the paleosols and the marine isotope stage 11(MIS 11) is suggested. Fil:Tófalo, O.R. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Orgeira, M.J. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Ramos, A.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Alonso, M.S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.

Phytophthora sojae causes root and stem rot, one of the most important diseases of soybean worldwide. Genetic diversity of 32 Phytophthora sojae isolates of different geographic origin from Argentina was evaluated with RAPD markers. The isolates were collected from diseased soybean plants and soil samples from Santa Fe, Buenos Aires, Córdoba and Entre Ríos provinces, in the Pampeana Region. DNA was amplified with 20 decanucleotides primers. Seven primers amplified 49 fragments, of which 35 were polymorphic, indicating high variability. RAPD analysis detected intraspecific variability even among isolates of the same geographic origin. © 2007 by The Mycological Society of America. Fil:Gally, M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Ramos, A.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Dokmetzian, D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Lopez, S.E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.