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Uno de los principales problemas que enfrentan los programas de mejoramiento genético en eucaliptos es la dificultad para identificar las especies e híbridos. El objetivo de este estudio fue encontrar marcadores moleculares asociados a cinco especies de Eucalyptus (E. saligna, E. tereticornis, E. urophylla, E. grandis and E. brassiana), mediante marcadores AFLP (Amplified Fragment Length Polymorphism) y BSA (Bulk Segregant Analysis), para su uso en programas de mejoramiento genético en Brasil. En 33 combinaciones de cebadores, se obtuvo un total de 868 fragmentos polimórficos, que representan un 91,65% del polimorfismo. Las mejores combinaciones que muestran potenciales marcadores para la identificación de especies, fueron encontradas en los cebadores M+GGT/E+ACC, que estuvo un 70% de los individuos asociados a la especie E. urophylla. Sin embargo, la combinación de cebadores compuesta de M+GGA/E+ACC identificó el 60% de individuos en la especie E. saligna; la combinación de los cebadores M+GTC/E +AAC, confirmó dos marcas, una en 60% y la otra en 50% para la identificación de individuos de la especie E. grandis. El tratamiento compuesto por los cebadores M+GGC/E+AAA, confirmó un 30% de los individuos perteneciente a la especie E. brassiana, siendo igual para la combinación de cebadores M+GGC/E+ACC, identificando el 30% de los individuos de la especie E. tereticornis. El análisis AFLP en asocio a BSA proporcionan una herramienta rápida para la identificación de cultivares en Eucalyptus, a la vez de que puede ser usados en los programas de mejoramiento genético forestal.

Brazil is a world reference in eucalyptus production due to its action based on sustainability, competitiveness and innovation. Accordingly, factors that affect production, such as diseases caused by pathogenic biotic agents, including those of fungal and bacterial origin, need to be studied. Bacteria encompass a group of pathogens of complex morphological differentiation, requiring studies to characterize them. Among the methods for separating bacterial groups, the biochemical characterization allows to distinguish these according to their characteristics, such as types of respiration, production of specific enzymes or carbohydrates, among others.Thus, 39 pathogenic isolates obtained through eucalyptus seedlings with symptoms of die-back and wilting and lesions on the branches, petiole and midrib were evaluated biochemically, in order to evaluate the pathogen group. Consequently, these isolates were submitted to the tests proposed by Schaad (2001), such as potassium hydroxide or Gram test (positive or negative), oxidation and fermentation test, hypersensitivity to tobacco (Nicotiana tabacum), pectinolytic enzyme production, reductive phosphatase activation, reduction of nitrate to nitrite, production of carbohydrates from mannitol and production of catalase.Therefore, the tests demonstrated the bacterium is Gram negative, that is, pathogenic. In addition, the results of the tests of the oxidation and fermentation, reductive phosphatase, nitrate to nitrite reduction, mannitol and catalase were positive and for pectinolytic enzyme production and hypersensitivity to tobacco were negative, indicating the isolates belong to the group of the Enterobacteria.

The aquatic plant species Egeria densa (Planch.) Casp and E. najas Planchon occur naturally in the Paraná River Basin of southeastern Brazil. Hydroelectric dam construction in the river basin has created several lakes, changing the ecology of the river and altering the population ecology of Egeria. Large, dense populations of Egeria now grow in Jupiá Lake and its tributaries, occasionally blocking hydroelectric turbines. This study is part of a larger project examining environmental changes associated with large dam projects; the research objective of this study was to assess patterns of genetic diversity in Egeria populations growing in Jupiá and Três Irmãos Lakes and their Paraná River tributaries using genetic markers. Forty-two plants of E. najas and 46 of E. densa (for a total of 88 samples) were collected from 13 sites. Genotypes were identified by isoenzymes and Random Amplification of Polymorphic DNA RAPD markers. Using a genetic distance dendrogram we grouped all E. densa plants into one set and all E. najas plants into another set. The plant sample 8a, which presented intermediary morphological characteristics of both species, also presented intermediary genetic characteristics, indicating the possibility that gene introgression between these Egeria species may occur. The creation of Três Irmãos Lake appears to have increased some measures of genetic diversity in Egeria populations by facilitating outcrossing among previously semi-isolated genotypes. Increased migration of large numbers of seeds and vegetative branches of E. densa and E. najas into Jupiá Lake and its tributaries can account for most of the changes in patterning of genetic diversity observed in these populations of Egeria. Las especies acuáticas de Egeria densa y E. najas ocurren naturalmente en la Cuenca del Río Paraná, sudeste del Brasil. La construcción de una represa hidroeléctrica en la cuenca de este río, creó varios lagos, cambiando la ecología del río y alterando la populación ecológica de Egeria. Grandes y densas poblaciones de Egeria crecen hoy en día en el lago de Jupiá y sus afluentes, bloqueando de vez en cuando las turbinas de la hidroeléctrica. Como parte de un estudio de cambios ambientales, asociados a grandes proyectos de represas, fueron usados marcadores moleculares para determinar patrones de diversidad genética en las poblaciones de Egeria que crecen en los lagos de Jupiá, Três Irmãos y sus afluentes del Río Paraná. En un total de 13 sitios, fueran colectadas 42 plantas de E. najas y 46 de E. densa, que suman un total de 88 muestras. Los genotipos fueron identificados por marcadores de isoenzimas y RAPD. A través de dendrogramas de distancia genética se agruparon por separado todas las plantas de E. densa y de E. najas. La muestra 8a presentó plantas con características morfológicas e genéticas intermediarias de ambas las especies, indicando haber posibilidades de introgresión de genes entre ambas las especies de Egeria. La creación del lago de Três Irmãos parece haber aumentado, en alguna medida, la diversidad genética de las populaciones de Egeria por la facilidad de cruzamientos entre genotipos, hasta entonces semi-aislados. La migración creciente de grandes cantidades de semillas y de partes vegetativas de Egeria densa y Egeria najas dentro del Lago Jupiá y sus afluentes, pueden explicar los cambios observados en los patrones de diversidad genética en estas populaciones de Egeria.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:23:37Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:40:48Z : No. of bitstreams: 1 2-s2.0-48249136922.pdf: 2047831 bytes, checksum: 5c268ad1b8e6541974691f63439f6697 (MD5) Made available in DSpace on 2014-05-27T11:23:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-01 The most significant studies about the spinner dolphin (Stenella longirostris) in the Southwestern Atlantic Ocean were conducted in Fernando de Noronha Archipelago, off Northeastern Brazil. The continuity of these studies depends upon the development of non-invasive methods. In this work, we present results from the skin swabbing sampling procedure for this species. We tested the performance of this method for nuclear and mitochondrial DNA analysis, unknown for this population. A total of skin 161 samples were collected during two expeditions. After the contacts the most of the dolphins remained close to the boat. Microsatellites markers and cytochrome b region primers were evaluated and the respective fragments were successfully amplified. Thus, skin swabbing may be considered an efficient strategy to obtain tissue samples for spinner dolphin genetic analysis in Fernando de Noronha Archipelago. Universidade Federal do Espírito Santo (UFES) Centro de Ciências Humanas e Naturais, Av Fernando Ferrari, 514, Vitória, ES, 29075-010 Campus Experimental do Litoral Paulista UNESP, Pça Infante D. Henrique, s/n, São Vicente, SP, 11330-205 Centro Mamíferos Aquáticos ICMBio, Vila do Boldró, s/n, Fernando de Noronha, PE Instituto de Biociências Departamento de Genética UNESP, Distrito de Rubião Jr., s/n, Botucatu, SP, 18618-000 Campus Experimental do Litoral Paulista UNESP, Pça Infante D. Henrique, s/n, São Vicente, SP, 11330-205 Instituto de Biociências Departamento de Genética UNESP, Distrito de Rubião Jr., s/n, Botucatu, SP, 18618-000

Corresponding author : e-mail cfmmenck@usp.br;; International audience; Over 40,000 sugarcane (Saccharum officinarum) consensus sequences assembled from 237,954 expressed sequence tags were compared with the protein and DNA sequences from other angiosperms, including the genomes of Arabidopsis and rice (Oryza sativa). Approximately two-thirds of the sugarcane transcriptome have similar sequences in Arabidopsis. These sequences may represent a core set of proteins or protein domains that are conserved among monocots and eudicots and probably encode for essential angiosperm functions. The remaining sequences represent putative monocot-specific genetic material, one-half of which were found only in sugarcane. These monocot-specific cDNAs represent either novelties or, in many cases, fast-evolving sequences that diverged substantially from their eudicot homologs. The wide comparative genome analysis presented here provides information on the evolutionary changes that underlie the divergence of monocots and eudicots. Our comparative analysis also led to the identification of several not yet annotated putative genes and possible gene loss events in Arabidopsis

A Egeria najas é uma espécie aquática submersa nativa da bacia hidrográfica do rio Paraná. Com o represamento das águas do rio para geração de energia elétrica a espécie tem mudado seu comportamento de colonização dos leitos dos rios e ocorrido em grandes maciços dentro da represa de Jupiá e rios afluentes. Essa planta tem causado problemas por obstruir a passagem de água para as turbinas de geração de energia elétrica. Coletas de material vegetativo foram realizadas na represa e afluentes do rio Paraná para análise da variabilidade isoenzimática e de DNA. A análise isoenzimática mostrou haver somente quatro classes de diferentes biotipos. No entanto, utilizando-se os procedimentos de RAPD, observou-se que a espécie possui grande variabilidade genética. O represamento das águas também está permitindo o acumulo de variabilidade no local e promovendo um aumento de variabilidade por meio de possíveis cruzamentos entre genótipos diferentes. Os resultados também possibilitaram inferir sobre as possíveis rotas de migração de material genético para colonização da represa e rios afluentes. The submerged aquatic species Egeria najas occurs naturally in the Parana River Basin - Brazil. Several lakes have been constructed by CESP - Centrais Elétricas do Estado de São Paulo S.A. in the river basin, changing the ecology of the region. The species have altered their establishment strategy, and now grows in large, dense populations on the floor of Jupia Lake and its tributaries. This has had a negative impact on electricity generation as the branches of these species routinely block the hydroelectric turbines. We used genetic markers to study the pattern of genetic diversity in the species using plant material collected along Jupia Lake and the Paraná River Tributaries. Isoenzymes have shown four different biotypes, however, the RAPD technique has demonstrated greater genetic variability among individuals. The creation of Jupia Lake has resulted in an increase in genetic variability probably by migration of large amount of seeds and vegetative branches. These materials are increasing the genetic diversity in populations in the lake by favoring outcrossing among different genotypes. Results also present a possible understanding of Egeria najas genotype migrations in populations in the Jupia Lake and its tributaries.