Brazilian coffee genome project: an EST-based genomic resource

O café é um dos principais produtos agrícolas, sendo considerado o segundo item em importância do comércio internacional de commodities. O gênero Coffea pertence à família Rubiaceae que também inclui outras plantas importantes. Este gênero contém aproximadamente 100 espécies, mas a produção comercial é baseada somente em duas espécies, Coffea arabica e Coffea canephora, que representam aproximadamente 70 % e 30 % do mercado total de café, respectivamente. O Projeto Genoma Café Brasileiro foi desenvolvido com o objetivo de disponibilizar os modernos recursos da genômica à comunidade científica e aos diferentes segmentos da cadeia produtiva do café. Para isso, foram seqüenciados 214.964 clones escolhidos aleatoriamente de 37 bibliotecas de cDNA de C. arabica, C. canephora e C. racemosa representando estádios específicos do desenvolvimento de células e de tecidos do cafeeiro, resultando em 130.792, 12.381 e 10.566 seqüências de cada espécie, respectivamente, após processo de trimagem. Os ESTs foram agrupados em 17.982 contigs e em 32.155 singletons. A comparação destas seqüências pelo programa BLAST revelou que 22 % não tiveram nenhuma similaridade significativa às seqüências no banco de dados do National Center for Biotechnology Information (de função conhecida ou desconhecida). A base de dados de ESTs do cafeeiro resultou na identificação de cerca de 33.000 unigenes diferentes. Os resultados de anotação das seqüências foram armazenados em base de dados online em http://www.lge.ibi.unicamp.br/cafe. Os recursos desenvolvidos por este projeto disponibilizam ferramentas genéticas e genômicas que podem ser decisivas para a sustentabilidade, a competitividade e a futura viabilidade da agroindústria cafeeira nos mercados interno e externo.

Seasonal changes in vegetative growth and photosynthesis of Arabica coffee trees

Seasonal changes in vegetative growth, leaf gas exchanges, carbon isotope discrimination (Delta) and carbohydrate status were monitored in de-fruited coffee trees (Coffea arabica L.) grown in the field, from October 1998 through September 1999, in Vicosa (20degrees45'S, 42degrees15'W, 650 m a.s.l.), southeastern Brazil. of the total growth over the 12-month study period, 78% occurred in the warm, rainy season (October-March), and 22% during the cool, dry season (April-September). Throughout the active growth period, the rate of net carbon assimilation (A) averaged 8.6 mumol m(-2) s(-1), against 3.4 mumol m(-2) s(-1) during the period of reduced growth. In the active period, growth, unlike A or Delta, was strongly negatively correlated with air temperature. In contrast, growth and A were both correlated positively, and Delta correlated negatively, with air temperature during the reduced growth period. However, the depressions of A and growth might have simply run in parallel, without any causal relationship. Changes in A appeared to be largely due to stomatal limitations in the active growing season, with non-stomatal ones prevailing in the slow growth period. Foliar carbohydrates seemed not to have contributed appreciably to changes in growth rates and photosynthesis. (C) 2004 Elsevier B.V. All rights reserved.

An evaluation of the genetic diversity of Xylella fastidiosa isolated from diseased citrus and coffee in São Paulo, Brazil

Strains of Xylella fastidiosa, isolated from sweet orange trees (Citrus sinensis) and coffee trees (Coffea arabica) with symptoms of citrus variegated chlorosis and Requeima do Cafe, respectively, were indistinguish able based on repetitive extragenic palindromic polymerase chain reaction (PCR) and enterobacterial repetitive intergenic consensus PCR assays. These strains were also indistinguishable with a previously described PCR assay that distinguished the citrus strains from all other strains of Xylella fastidiosa. Because we were not able to document any genomic diversity in our collection of Xylella fastidiosa strains isolated from diseased citrus, the observed gradient of increasing disease severity from southern to northern regions of São Paulo State is unlikely due to the presence of significantly different strains of the pathogen in the different regions. When comparisons were made to reference strains of Xylella fastidiosa isolated from other hosts using these methods, four groups were consistently identified consistent with the hosts and regions from which the strains originated: citrus and coffee, grapevine and almond, mulberry, and elm, plum, and oak. Independent results from random amplified polymorphic DNA (RAPD) PCR assays were also consistent with these results; however, two of the primers tested in RAPD-PCR were able to distinguish the coffee and citrus strains. Sequence comparisons of a PCR product amplified from all strains of Xylella fastidiosa confirmed the presence of a CfoI polymorphism that can be used to distinguish the citrus strains from all others. The ability to distinguish Xylella fastidiosa strains from citrus and coffee with a PCR-based assay will be useful in epidemiological and etiological studies of this pathogen.

Transposable elements in Coffea (Gentianales : Rubiacea) transcripts and their role in the origin of protein diversity in flowering plants

Transposable elements are major components of plant genomes and they influence their evolution, acting as recombination hot spots, acquiring specific cell functions or becoming part of protein-coding regions. The latter is the subject of the present analysis. This study is a report on the annotation of transposable elements (TEs) in expressed sequences of Coffea arabica, Coffea canephora and Coffea racemosa, showing the occurrence of 383 ESTs and 142 unigenes with TE fragments in these three Coffea species. Based on selected unigenes, it was possible to suggest 26 putative proteins with TE-cassette insertions, demonstrating a likely contribution to protein variability. The genes for two of those proteins, the fertility restorer (FR) and the pyrophosphate-dependent phosphofructokinase (PPi-PFKs) genes, were selected for evaluating the impact of TE-cassettes on host gene evolution of other plant genomes (Arabidopsis thaliana, Oryza sativa and populus trichocarpa). This survey allowed identifying a FR gene in O. sativa harboring multiple insertions of LTR retrotransposons that originated new exons, which however does not necessarily mean a case of molecular domestication. A possible transduction event of a fragment of the PPi-PFK beta-subunit gene mediated by Helitron ATREPX1 in Arabidopsis thaliana was also highlighted.

FISH using a gag-like fragment probe reveals a common Ty3-gypsy-like retrotransposon in genome of Coffea species

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Antioxidant enzyme activity and hydrogen peroxide content during the drying of Arabica coffee beans

The development of the germination process and drought stress during the drying of coffee can generate reactive oxygen species, which can be neutralized by way of antioxidant mechanisms. No studies related to antioxidant enzymes during the drying of coffee were found in the literature, and considering their importance, the enzymatic activities of superoxide dismutase (SOD), guaiacol peroxidase (GPOX) and glutathione reductase (GR), and also the hydrogen peroxide content were evaluated during the drying of two types of coffee bean, one processed as natural coffee and the other as pulped natural coffee. The results showed a reduction in the SOD, GPOX and GR enzymatic activities of the natural coffee as compared to the pulped natural coffee during the drying period. Moreover, the hydrogen peroxide content of the natural coffee was greater than that of the pulped natural coffee. These results suggest the development of oxidative stress during the coffee drying process, controlled more efficiently in pulped natural coffee by the early action of GPOX during the drying process. Nevertheless, differential responses by SOD isoenzymes and possibly the role of other peroxidases also appear to be involved in the responses observed. © 2013 Springer-Verlag Berlin Heidelberg.

Eficiência da aplicação de resíduo biológico do branqueamento de argila como quelatizante de zinco na adubação foliar do cafeeiro (Coffea arábica L.)

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Isolamento e caracterização de um gene que codifica uma isofalvona redutase like de café(Coffea arábica L.) e análise de sua região promotora

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Resposta fisiológica e bioquímica do cafeeiro (Coffea arábica, L.) cv. Catuai Vermelho IAC 144, em função de modos aplicação e doses de nitrogênio

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of potassium sources and rates on arabica coffee yield, nutrition, and macronutrient export

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Irrigation and intercropping with macadamia increase initial arabica coffee yield and profitability

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Gene expression profile during coffee fruit development and identification of candidate markers for phenological stages

The objective of this work was to identify genes that could be used as suitable markers for molecular recognition of phenological stages during coffee (Coffea arabica) fruit development. Four cultivars were evaluated as to their differential expression of genes associated to fruit development and maturation processes. Gene expression was characterized by both semi-quantitative and quantitative RT-PCR, in fruit harvested at seven different developmental stages, during three different seasons. No size polymorphisms or differential expression were observed among the cultivars for the evaluated genes; however, distinct expression profiles along fruit development were determined for each gene. Four out of the 28 evaluated genes exhibited a regular expression profile in all cultivars and harvest seasons, and, therefore, they were validated as candidate phenological markers of coffee fruit. The gene a-galactosidase can be used as a marker of green stage, caffeine synthase as a marker of transition to green and yellowish-green stages, and isocitrate lyase and ethylene receptor 3 as markers of late maturation.

Efeitos fisiológicos da coffea arábica e coffea canephora

Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz

Estabelecimento de microestacas excisadas de vitroplantas de cafeeiro arabica três meses após a indução.

A propagação vegetativa por enraizamento de estacas é pouco difundida para cafeeiros arabica. São poucos os trabalhos publicados e há muito o que ser avaliado. Neste trabalho o estabelecimento de microestacas induzidas em vitroplantas geradas por embriogênese somática foi avaliado. As vitroplantas de Siriema clone 3 e de Catucaí 567, cultivares produtivas resistentes à ferrugem, foram produzidas seguindo rotina do Laboratório de Cultura de Tecidos da SAPC/Fundação Procafé, Varginha/MG. No terceiro mês de aclimatização, as vitroplantas foram decapitadas e aspergidas com TIBA (ac. triiodobenzóico) a 200, 400 e 600 mg.L-1. Brotações apicais foram coletadas dois meses após a indução, cada nó de cada brotação com um par de meias-folhas formou uma microestaca, que foi tratada em solução fungicida e levada a enraizar em bandejas de 128 células com substrato de fibra de coco. Microestacas que não enraizaram até 90 dias foram tratadas com ac. naftalenacético a 200 mg.L-1.

Avaliação da indução de brotações sobre mudas de estacas como forma de acelerar a propagação vegetativa de cafeeiros arabica.

A micropropagação de cafeeiros é técnica importante para obtenção simultânea de um grande número de plantas clonadas utilizando fragmentos pequenos de matrizes selecionadas. No entanto, o tempo necessário para a conclusão do processo de embriogênese somática encarece as mudas. O manejo das vitroplantas após a aclimatização pode melhorar o custo-benefício da técnica. O objetivo deste trabalho foi avaliar a eficiência da indução de brotações em vitroplantas de cafeeiro arábica utilizando o regulador de crescimento ácido triiodobenzóico (TIBA), para amplificar os clones obtidos in vitro. As vitroplantas foram geradas por embriogênese somática induzida em segmentos foliares de cafeeiros Siriema clone 3 e de Catucaí 567, cultivares produtivas resistentes à ferrugem, seguindo o protocolo utilizado pelo Laboratório de Cultura de Tecidos da SAPC/Fundação Procafé, Varginha/MG.