We report novel features of the genome sequence of Leptospira interrogans serovar Copenhageni, a highly invasive spirochete. Leptospira species colonize a significant proportion of rodent populations worldwide and produce life-threatening infections in mammals. Genomic sequence analysis reveals the presence of a competent transport system with 13 families of genes encoding for major transporters including a three-member component efflux system compatible with the long-term survival of this organism. The leptospiral genome contains a broad array of genes encoding regulatory system, signal transduction and methyl-accepting chemotaxis proteins, reflecting the organism's ability to respond to diverse environmental stimuli. The identification of a complete set of genes encoding the enzymes for the cobalamin biosynthetic pathway and the novel coding genes related to lipopolysaccharide biosynthesis should bring new light to the study of Leptospira physiology. Genes related to toxins, lipoproteins and several surface-exposed proteins may facilitate a better understanding of the Leptospira pathogenesis and may serve as potential candidates for vaccine.

Coffee is one of the most valuable agricultural commodities and ranks second on international trade exchanges. The genus Coffea belongs to the Rubiaceae family which includes other important plants. The genus contains about 100 species but commercial production is based only on two species, Coffea arabica and Coffea canephora that represent about 70 % and 30 % of the total coffee market, respectively. The Brazilian Coffee Genome Project was designed with the objective of making modern genomics resources available to the coffee scientific community, working on different aspects of the coffee production chain. We have single-pass sequenced a total of 214,964 randomly picked clones from 37 cDNA libraries of C. arabica, C. canephora and C. racemosa, representing specific stages of cells and plant development that after trimming resulted in 130,792, 12,381 and 10,566 sequences for each species, respectively. The ESTs clustered into 17,982 clusters and 32,155 singletons. Blast analysis of these sequences revealed that 22 % had no significant matches to sequences in the National Center for Biotechnology Information database (of known or unknown function). The generated coffee EST database resulted in the identification of close to 33,000 different unigenes. Annotated sequencing results have been stored in an online database at http: //www.lge.ibi.unicamp.br/cafe. Resources developed in this project provide genetic and genomic tools that may hold the key to the sustainability, competitiveness and future viability of the coffee industry in local and international markets. Key words: Coffea, cDNA, EST, transcriptome.Projeto Genoma Brasileiro Café: recursos genômicos baseados em ESTs: 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...

The use of monogenic race-specific resistance is widespread for the control of maize (Zea mays L.) helminthosporiosis caused by Exserohilum turcicum. Inoculation of 18 Brazilian isolates of E. turcicum onto elite maize lines containing previously identified resistance genes and onto differential near-isogenic lines allowed the identification of new qualitative resistance genes. The inoculation of one selected isolate on differential near-isogenic lines, F 1 generations and a BC 1 F 1 population from the referred elite lines enabled the characterization of the resistance spectrum of three new genes, one dominant (HtP), one recessive (rt) and a third with non-identified genetic action. Three physiological races of the pathogen were also identified including two with new virulence factors capable of overcoming the resistance of one of the resistance genes identified here (rt).

The cultivated passion fruit (Passiflora edulis f. flavicarpa) is a cross-pollinated species native to South America. In the current study, a segregating F1 population derived from a single cross between the clones IAPAR-06 and IAPAR-123 was used to construct AFLP-based linkage maps and to map resistance genes to bacterial spot caused by Xanthomonas axonopodis pv. passiflorae. Linkage analysis was performed by the 2-way pseudo-testcross mapping method using markers that segregated in a 1:1 ratio. The IAPAR-06 linkage map was constructed using 115 markers, 112 of which were allocated to 9 linkage groups (LG) covering 790.2 cM. The map of IAPAR-123 was constructed using 140 markers, 138 of which were allocated to 9 LG covering 488.9 cM. In both maps, clusters of markers were detected, indicating that the AFLP markers were not distributed at random. Bacterial resistance was assessed by measuring the diseased leaf area after wound-inoculating the leaves of F1 plants. Quantitative resistance loci (QRLs) mapping was carried out by composite interval mapping and 1 QRL was detected, which explained 15.8% of the total phenotypic variation. The possibility of considering these data for marker-assisted selection in passion fruit breeding programs is discussed.

Among the 372 phytophagous Hemiptera examined, 133 insects of 28 species (Coreidae 18, Pentatomidae 7, Pyrrhocoridae 2, Lygaeidae 1) were infected with trypanosomatids. Gut infections only were found in 68.4%, gut and salivary gland infections in 29.3% and salivary infections alone in 2.3%. Fifty‐one cultures were isolated from 38 insects. Cultures were characterized by assay of certain ornithinc‐arginine metabolism enzymes and by indirect immunofluorescence against monoclonal antibodies specific for Phytomonas spp. Ten cultures were identified as either Crithidia or Leptomonas. Twenty‐one promastigote cultures had an enzyme pattern hitherto recorded only for Leishmania and 16 cultures were identified as Phytomonas.

Em experimento realizado em casa de vegetação com quatro linhagens e dois híbridos de milho (Zea mays), verificou-se variabilidade para resistência a queima foliar causada por Colletotrichum graminicola avaliada por meio das variáveis área total de lesão por planta (ATL), área média de lesão (AML), comprimento total de lesão por planta (CTL), comprimento médio de lesão (CML) e número de lesões por planta (NL). Quando dois isolados de C. graminicola foram inoculados nessas linhagens e em híbridos de milho não foi verificada interação diferencial entre isolados e genótipos do hospedeiro. Em estudos de herança da resistência, as linhagens genitoras L186 e L64 comportaram-se como suscetível e resistente, respectivamente, ao passo que o híbrido L186 x L64 apresentou resistência. A análise das freqüências observadas de plantas resistentes e suscetíveis na população F2 resultantes da autofecundação do híbrido, indicou ocorrência de herança monogênica com dominância completa para o alelo que confere resistência à doença.

No abstract

Populations of Dalbulus maidis (DeLong and Wolcott) from the northeastern and central-southern regions of Brazil differ morphologically, suggesting that they could be genetically isolated. Here we used the random amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR) technique to estimate genetic structuring of this leafhopper species among five geographically distant localities across those regions and to estimate gene flow between populations. Ten specimens were sampled per population and genotyped with RAPD markers generated from amplification with nine oligonucleotides. The percentage of polymorphic loci was 78% in relation to the total number of amplified loci, and genetic similarity either between or within populations was higher than 0.72. Cluster analysis grouped specimens from the northeastern population (Mossoró/RN) into a single group, whereas central-southern specimens were not grouped in relation to their places of origin. Overall, the genetic subdivision index (Fst) was low (or= 0.192 and Nm