Caracterização de novos microssatélites desenvolvidos a partir do transcriptoma de amendoim forrageiro.

O amendoim forrageiro tem ganhado cada vez mais importância devido às vantagens associadas ao seu uso. Entretanto, a quantidade de microssatélites disponíveis para a espécie ainda é restrita, o que tem sido um gargalo no avanço do programa de melhoramento. Nesse sentido, o objetivo deste trabalho foi desenvolver e caracterizar novos microssatélites a partir do transcriptoma de folhas de Arachis pintoi. Foram testados 186 locos em 19 acessos. Os locos com os melhores perfis de amplificação (64) foram selecionados para avaliação de polimorfismo, dos quais 63 (98,4%) apresentaram perfis polimórficos, com média de 7,37 alelos por loco. Os valores médios de heterozigosidade esperada (HE) e observada (HO) foram 0,72 e 0,31, respectivamente. Os marcadores apresentaram elevadas médias de conteúdo de informação polimórfica (PIC = 0,70) e poder discriminatório (D = 0,80). Portanto, os novos marcadores derivados de genes são informativos e podem ser incorporados à rotina de análises do programa de melhoramento.Editores técnicos: Rodrigo Souza Santos; Fabiano Marçal Estanislau

Caracterização funcional do transcriptoma de amendoim forrageiro.

O uso do amendoim forrageiro em consórcios com gramíneas nas pastagens e como cobertura verde, consorciado com culturas comerciais, tem crescido nos últimos anos. A análise do genoma funcional permite a identificação de genes de interesse agronômico. Assim, o objetivo deste trabalho foi realizar a anotação funcional de genes do transcriptoma de folhas de Arachis pintoi. Dos 98.432 transcritos analisados, 69% apresentaram correspondências com o banco de dados de proteínas do National Center of Biotechnology Information. As classes função molecular (36%) e processo biológico (35,8%) representaram a maioria dos termos de Gene Ontology atribuídos, enquanto o componente celular (28,2%) apresentou menor número. A análise de expressão diferencial identificou 1.550 e 1.357 genes com maior nível de expressão nas cultivares Amarillo e Belomonte, respectivamente. A análise de enriquecimento dos genes mostrou que 55,63% pertencem à classe componente celular, seguida por função molecular (26,48%) e processo biológico (20,89%). Esses resultados são o primeiro relato de anotação funcional de A. pintoi que irá fornecer uma importante fonte de informação para avanços nos estudos de expressão, silenciamento e edição gênica nos programas de melhoramento de Arachis.Editores técnicos: Rodrigo Souza Santos; Fabiano Marçal Estanislau

Gestão conservacionista de solo e de água em escala de microbacia hidrográfica: estudo de caso.

bitstream/CNPT-2010/40705/1/p-do87.pd

Biochemical and phylogenetic characterization of the wastewater tolerant Chlamydomonas biconvexa Embrapa|LBA40 strain cultivated in palm oil mill effluent.

The increasing demand for water, food and energy poses challenges for the world´s sustainability. Tropical palm oil is currently the major source of vegetable oil worldwide with a production that exceeds 55 million tons per year, while generating over 200 million tons of palm oil mill effluent (POME). It could potentially be used as a substrate for production of microalgal biomass though. In this study, the microalgal strain Chlamydomonas biconvexa Embrapa|LBA40, originally isolated from a sugarcane vinasse stabilization pond, was selected among 17 strains tested for growth in POME retrieved from anaerobic ponds of a palm oil industrial plant located within the Amazon rainforest region. During cultivation in POME, C. biconvexa Embrapa|LBA40 biomass productivity reached 190.60 mgDW ? L-1 ? d-1 using 15L airlift flat plate photobioreactors. Carbohydrates comprised the major fraction of algal biomass (31.96%), while the lipidic fraction reached up to 11.3% of dry mass. Reductions of 99% in ammonium and nitrite, as well as 98% reduction in phosphate present in POME were detected after 5 days of algal cultivation. This suggests that the aerobic pond stage, usually used in palm oil industrial plants to reduce POME inorganic load, could be substituted by high rate photobioreactors, significantly reducing the time and area requirements for wastewater treatment. In addition, the complete mitochondrial genome of C. biconvexa Embrapa|LBA40 strain was sequenced, revealing a compact mitogenome, with 15.98 kb in size, a total of 14 genes, of which 9 are protein coding genes. Phylogenetic analysis confirmed the strain taxonomic status within the Chlamydomonas genus, opening up opportunities for future genetic modification and molecular breeding programs in these species

O Programa de PD&I em Ômica de Palma de Óleo (Elaeis spp.) na Embrapa Agroenergia.

bitstream/item/173812/1/DOC-28-CNPAE.pd

Comparative modeling of DNA and RNA polymerases from Moniliophthora perniciosa mitochondrial plasmid

<p>Abstract</p> <p>Background</p> <p>The filamentous fungus <it>Moniliophthora perniciosa </it>(Stahel) Aime & Phillips-Mora is a hemibiotrophic Basidiomycota that causes witches' broom disease of cocoa (<it>Theobroma cacao </it>L.). This disease has resulted in a severe decrease in Brazilian cocoa production, which changed the position of Brazil in the market from the second largest cocoa exporter to a cocoa importer. Fungal mitochondrial plasmids are usually invertrons encoding DNA and RNA polymerases. Plasmid insertions into host mitochondrial genomes are probably associated with modifications in host generation time, which can be involved in fungal aging. This association suggests activity of polymerases, and these can be used as new targets for drugs against mitochondrial activity of fungi, more specifically against witches' broom disease. Sequencing and modeling: DNA and RNA polymerases of <it>M. perniciosa </it>mitochondrial plasmid were completely sequenced and their models were carried out by Comparative Homology approach. The sequences of DNA and RNA polymerase showed 25% of identity to 1XHX and 1ARO (pdb code) using BLASTp, which were used as templates. The models were constructed using Swiss PDB-Viewer and refined with a set of Molecular Mechanics (MM) and Molecular Dynamics (MD) in water carried out with AMBER 8.0, both working under the ff99 force fields, respectively. Ramachandran plots were generated by Procheck 3.0 and exhibited models with 97% and 98% for DNA and RNA polymerases, respectively. MD simulations in water showed models with thermodynamic stability after 2000 ps and 300 K of simulation.</p> <p>Conclusion</p> <p>This work contributes to the development of new alternatives for controlling the fungal agent of witches' broom disease.</p

A genome survey of Moniliophthora perniciosa gives new insights into Witches' Broom Disease of cacao

<p>Abstract</p> <p>Background</p> <p>The basidiomycete fungus <it>Moniliophthora perniciosa </it>is the causal agent of Witches' Broom Disease (WBD) in cacao (<it>Theobroma cacao</it>). It is a hemibiotrophic pathogen that colonizes the apoplast of cacao's meristematic tissues as a biotrophic pathogen, switching to a saprotrophic lifestyle during later stages of infection. <it>M. perniciosa</it>, together with the related species <it>M. roreri</it>, are pathogens of aerial parts of the plant, an uncommon characteristic in the order Agaricales. A genome survey (1.9× coverage) of <it>M. perniciosa </it>was analyzed to evaluate the overall gene content of this phytopathogen.</p> <p>Results</p> <p>Genes encoding proteins involved in retrotransposition, reactive oxygen species (ROS) resistance, drug efflux transport and cell wall degradation were identified. The great number of genes encoding cytochrome P450 monooxygenases (1.15% of gene models) indicates that <it>M. perniciosa </it>has a great potential for detoxification, production of toxins and hormones; which may confer a high adaptive ability to the fungus. We have also discovered new genes encoding putative secreted polypeptides rich in cysteine, as well as genes related to methylotrophy and plant hormone biosynthesis (gibberellin and auxin). Analysis of gene families indicated that <it>M. perniciosa </it>have similar amounts of carboxylesterases and repertoires of plant cell wall degrading enzymes as other hemibiotrophic fungi. In addition, an approach for normalization of gene family data using incomplete genome data was developed and applied in <it>M. perniciosa </it>genome survey.</p> <p>Conclusion</p> <p>This genome survey gives an overview of the <it>M. perniciosa </it>genome, and reveals that a significant portion is involved in stress adaptation and plant necrosis, two necessary characteristics for a hemibiotrophic fungus to fulfill its infection cycle. Our analysis provides new evidence revealing potential adaptive traits that may play major roles in the mechanisms of pathogenicity in the <it>M. perniciosa</it>/cacao pathosystem.</p