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Context The Brachiaria genus includes several species of pastures distributed in tropical and subtropical regions. Plant growth-promoting bacteria (PGPB), such as Azospirillum brasilense, have been used as inoculants to increase crop production. Aims This study explored the effect of A. brasilense on Brachiaria seedlings, rhizosphere, and soil. Methods We inoculated A. brasilense on Brachiaria seeds sown in two types of soil mainly varying in texture (medium texture-Mt and clayey-C soils). We then collected the rhizosphere to evaluate the microbiota adhered to the plants by high-throughput 16S sequencing using bioinformatic tools. Shoot and root biomass were also evaluated. Key results Inoculation increased the aerial biomass of Brachiaria plants. However, it did not increase root biomass. Soil texture is a critical element in shaping rhizosphere communities. A. brasilense decreased the abundance of Firmicutes, mainly in C Oxisols. Network analysis showed that Proteobacteria, Acidobacteria, Actinobacteria, Firmicutes, and Bacteroidetes were the main phyla in the vicinity of Brachiaria roots. Furthermore, the abundance of specific phyla, such as Armatimonadetes, Tenericutes, and Fusobacteria (Mt) and Latescibacteria, Rokubacteria, and WS2 (C) increased in the bulk fraction. In the rhizosphere, Chlamydiae was exclusively related to Mt Oxisols. By contrast, Verrumicrobia and Fusobacteria were only found in the C soils. Conclusions Relative abundance of Acidobacteria and Actinobacteria increased after inoculation in the rhizosphere of both types of Oxisols. Implications These results indicate that inoculation can affect Brachiaria plants and their rhizospheric bacterial communities. The effect of taxonomic groups altered through inoculation and the relationship between the functional capacities of each group within the microbiota are yet to be elucidated.

O objetivo deste trabalho foi avaliar a eficiência do A. brasiliense, associado a diferentes doses de N em cobertura, no desempenho agronômico do milho e nos atributos biológicos do solo. O experimento foi conduzido seguindo o delineamento em blocos casualizados, com 4 repetições e os seguintes tratamentos: T1) Somente sob inoculação com A. brasiliense na dose comercial (AZO); T2) Somente sob aplicação de 150 kg ha-1 de N em cobertura; T3) AZO + 50 kg ha-1 N em cobertura; T4) AZO + 100 kg ha-1 de N em cobertura; T5) AZO + 150 kg ha-1 de N em cobertura; T6) Controle (sem inoculação e sem N de cobertura). Foram avaliados: altura de planta (ALT), altura de inserção de espiga (AIE), número de grãos por fileira (NGF), massa seca da parte aérea (MSPA), respiração basal do solo (RBS), unidades formadoras de colônia (UFC), diversidade morfológica bacteriana e produtividade (PROD). Os valores de RBS indicam que, nas condições padrões do solo (T6), havia uma maior atividade metabólica que foi equacionada pela adubação de N de cobertura isolada (T2) e associada na AZO + 100 kg ha-1 (T4). Sob AZO + N cobertura a 150 kg ha-1, foi observado aumento da RBS com redução da produtividade em relação ao T4. Não houve diferenças significativas para os dados de densidade bacteriana (UFC), mas o estudo de diversidade revelou que a adubação com cama aviária contribuiu para a manutenção do equilíbrio biológico do solo. Por isso, o sistema acabou sofrendo pouca influência dos tratamentos experimentais, no entanto, a produtividade do T6 (6200 kg ha-1) foi a menor dentre todos os tratamentos. Considerando todos os aspectos avaliados, o T4 sob inoculação de A. brasiliense + N cobertura a 100 kg ha-1 foi o que apresentou os melhores resultados biológicos e agronômicos, diferenciando significativamente dos demais com a maior produtividade alcançada (8500 kg ha-1).

In this study, we identified the presence and quantity of flavonoids produced in wheat roots inoculated with rhizobacteria. Our goal is to confirm the efficiency of standard isolates and show new strains with biotechnological potential to promote plant growth. The experiment was carried out with different isolates under inoculation in the following situations: T1-Azospirillum brasiliense; T2-Herbaspirillum seropedicae; T3-Azospirillum brasiliense and Herbaspirillum seropedicae co-inoculation; T4-native Enterobacter sp. nº 203; T5- native Enterobacter sp. nº 208; T6-native Enterobacter sp. nº 493; T7-Control only under nitrogen fertilization (N+); T8-Control without nitrogen (N-) and bacterial inoculation. Agronomic characteristics were assessed after 42 days of inoculation. Identification and quantification of flavonoids were carried out through HPLC, using an analytical curve with four standards based on Coumarin, Quercetin, Isoflavone and Rutin. Regarding the production of total flavonoids, two (203 and 493) out of the three native strains we tested were statistically significant, exceeding the values obtained from the inoculation of standard strains, which presented association with grasses (Azopirilum e Herbaspirillum). Standard bacteria, when inoculated in isolation, presented, along with those that received N+ treatment, the highest values for length and root and aerial part dry mass. New studies need to be carried out in order to confirm the technological use of these native strains as inoculant, as these bacteria may contribute to Biological Nitrogen Fixation (BNF) in wheat culture, either by competition or synergism.

The present work evaluated the segregation of the RR-biotechnology and the agronomic performance of maize hybrids originated from three seed categories: single-cross commercial hybrids, double-cross hybrids, and saved seeds (F2 population). The experiment was set up in the field, within a producing area used for market purposes, in São Miguel do Iguaçu, Paraná, Brazil. The research followed a randomized block design with four repetitions. We investigated the following treatments: saved seeds/F2 population (MG 580 PW, MG 30A37 PW, MG 600 PW, and MG 545 PW), seeds of single-cross commercial hybrids (MG 580 PW, MG 30A37 PW, AS 1777 PRO3, AG 9000 PRO3, and DKB 290 PRO3) and home-bred seeds/double-cross hybrids (DKB 290 PRO3 x MG 30A37 PW, DKB 290 PRO3 x DKB 285 PEO3, DKB 290 PRO3 x DOW 2B587 PW, and DKB 290 PRO3 x MG 600 PW). The study considered agronomical characters, as well as the segregation of the RR-biotechnology. The hybrids MG 580 PW and DKB 290 PRO3 were the most productive ones, yielding 9,244.31 and 9,151.84 kg ha-1, respectively. The groups formed by double-cross and F2-population hybrids had the highest average values of RR-biotechnology segregation (20.5% and 13%, respectively). The group of commercial hybrids proved to be superior to the others in all variables appraised, and they also did not show segregation of the RR-biotechnology. The principal component analysis made it possible to sort the three categories of seeds. In conclusion, despite the high cost, the commercial seeds stood out showing the best cost-benefit for maize crops.

No Brasil exploração da suinocultura é uma atividade pecuária muito importante sob vários aspectos, pois, promove a geração de emprego e renda no meio rural, mas por outro lado, é responsável pela produção de grandes quantidades de dejetos como a Água Residuária da Suinocultura (ARS). Este estudo objetivou avaliar as alterações quantitativas dos principais atributos químicos do solo e nas características morfométricas de mudas de arbóreas adubadas com diferentes doses de ARS. O experimento foi conduzido na área de experimentação ambiental da Universidade Federal do Paraná - Setor Palotina. O delineamento utilizado foi em blocos casualizados (DBC) onde foram testados seis tratamentos com diferentes doses de ARS, sendo: T1= 0 L m-2, T2= 1 L m-2, T3= 2 L m-2,T4= 3 L m-2, T5= 4 L m-2, T6= 5 L m-2 aplicados para adubação de mudas de Citharexylum myrianthum Cham. A aplicação do residuo resultou em aumento do percentual de matéria orgânica na camada de 0 a 20 cm juntamente com os teores de K+, Mn+2, Zn+, Cu+, Fe, CTC, saturação por Al+3 e H+3+ Al+3 e diminuição do pH, dos teores de Ca+2, Mg+2 e da saturação por bases. Quanto ao crescimento das mudas os maiores valores de incrementos tanto de altura como em diâmetro foram identificados nas plantas que receberam as doses de 5 L m-2 de ARS.

Cultivation of small fruits such as blackberry, raspberry, blueberry, strawberry, and physalis is rapidly growing in Brazil, mainly due to small producers who seek income diversification. The aim of this study was to evaluate the effect of foliar application of different doses of chitosan on the physicochemical properties of Physalis peruviana L. Two experiments were conducted: i) field (FE); and ii) greenhouse (GE). Four doses of chitosan (0.1, 0.2, 0.3, and 0.4 L 100L-1) and a control were used as treatments. We evaluated fruit diameter (FD), fruit length (FL), calyx length (CL), and calyx diameter (CD) - mm; fruit mass - g; soluble solids content (SS) - °Brix; titratable acidity (TA) - % of citric acid; SS/TA ratio; and fruit firmness - N. Foliar application of chitosan to field-grown physalis plants significantly increased fruit mass, length, and diameter, as well as fruit SS and TA content. However, in a protected environment, the application of chitosan had less effect on the properties evaluated. Fruit firmness was not affected by chitosan application. Negative correlations (P

From an economic point of view, swine stands out as an important exploitation of brazilian livestock farming, promoting employment and income generation in rural areas. However, this activity becomes environmentally problematic because it produces large quantities of swine wastewater (ars), but has potential to be used as fertilizer. The present work had as objective to determine the dose of ars that would best provides increment of height and diameter in seedlings of luehea divaricata mart. & zucc. (malvaceae). The experimental design was randomized blocks with four replications and four seedlings per plot totaling 80 seedlings. each plot received the following ars doses: 0, 12.5, 25, 37.5 and 50 m3 ha-1. the results confirmed statistical differences between the average height of the seedlings in relation to the applied doses. The plants that received doses of 50 m3 ha-1 presented higher average and maximum value of diametric growth and height. The application of ars showed positive results in the fertilization of tree seedlings, besides allowing a further route for the destination of this residue contributing to the reduction of environmental risks caused by its irregular destination.

A planta de pinhão manso encontra-se entre as culturas com grande potencial energético, devido à grande concentração de óleo nas suas sementes, e seu alto poder calorífico. Entretanto, a maturação desuniforme é um problema na colheita, principalmente levando em consideração o melhor momento para se colher os frutos visando maior rendimento de óleo. Neste sentido, este trabalho teve como objetivo avaliar quais características dos frutos de pinhão manso indicam a melhor época para colheita visando maior rendimento de teor de óleo nas sementes. Para tal, coletaram-se em 2013 e 2014 frutos de pinhão-manso em diferentes estádios de maturação: frutos verdes escuros (VE), frutos amarelos (AM), frutos marrom-amarelados (MA) e frutos marrons na planta (MP). Destes, avaliou-se, tanto das sementes como dos frutos, o comprimento, largura, espessura e a massa seca. Dos frutos avaliou-se ainda a porcentagem de umidade, e das sementes avaliou-se o teor de óleo. Tanto em 2013 como em 2014, para as variáveis relacionadas com dimensões (comprimento, largura e espessura), tanto nos frutos como nas sementes, as maiores médias foram obtidas pelos frutos verdes. Em contrapartida, tanto para os frutos como para as sementes, observou-se que os frutos mais maduros apresentam maior matéria seca onde obteve-se médias de 60,28% e 92,52 em 2013 e 62,79% e 80,31% em 2014 respectivamente para MA e MP. Já quanto ao teor de óleo os estádios de maturação mais adequados à colheita de pinhão manso encontram-se imediatamente após o amarelecimento dos frutos, quando os mesmos apresentam quantidade de óleo mais elevada.

With the objective of developing new SSR markers for Coffea arabica, two enriched genomic libraries with probes (GT)15 and (AGG)10 were constructed. A total of 835 clones were sequenced and 756 presented good quality sequences. Redundant sequences were observed for 113 clones (14.94%). SSRs were found in 287 clones (38%). An estimated size of 417.5Kb of the C. arabica genome was sampled, with an average of one SSR per 1.46Kb. Dinucleotide repeats were more frequent than trinucleotides. Four repeat sequences, (AG/CT)n, (AC/GT)n, (AAG/CTT)n, and (AGG/CCT)n represented 61.1% of the total observed. A total of 96 SSR primers were designed and tested by PCR for two C. arabica genotypes. Ninety new SSR markers were validated for further genetic studies of C. arabica. Made available in DSpace on 2011-04-09T22:27:59Z (GMT). No. of bitstreams: 1 Developmentandvalidation.pdf: 198957 bytes, checksum: e91368d60426471fcd013866666b14f9 (MD5) Previous issue date: 2011-03-10

Since abiotic and biotic factors can compromise the survival of bacteria and their viability, encapsulation of cells in biodegradable gel matrices, a biological macromolecule, is one alternative to have their shelf life extended. Here, it was developed a gel-based formulation of the bioinoculant Azospirillum brasilense strain AbV5 and determined the effect of trehalose and humic acid supplementation in viability and survival of bacteria. For each 2 ml of sodium alginate solution (3%), 1 ml of the inoculum was extruded in a solution containing sodium alginate complexed with calcium chloride, forming calcium alginate beads. Supplements were used in a ratio of 2:2:1. Treatments were peat; alginate; alginate + humic acid; alginate + trehalose 0.1 M; alginate + trehalose 1 M. Morphometric aspects, survival rate and viability were determined in 9 storage periods (3, 5, 7, 14, 21, 30, 45, 60, 90 days). As results, beads were able to sustain the growth of A. brasilense for 90 days. Shelf life quality decreased in all treatments and peat remained the best carrier. Encapsulation, despite promoting the greatest losses in the survival of bacteria in the first days, ensured better cell viability. Trehalose in low concentrations (0.1M) improved cell viability during storage, optimizing plant inoculation.

The objective of this paper was to assess and identify the causes of senescence in Jatropha curcas L. plants. Morphological, physiological and agricultural parameters in non-irrigated and daily irrigated plants by drip irrigation system were evaluated. The characteristics evaluated were soil humidity, the number of leafs, rate of branches growth, increase of branches diameter, relative water content, photosynthesis, transpiration, stomatal conductance, internal CO2 concentration/environment ratio, nitrogen content, specific leaf area, carotenoids, total chlorophyll, chlorophyll/carotenoids ratio, a/b chlorophyll ratio, total chlorophyll/nitrogen ratio, maximum and minimum air temperature, temperature range and nitrate reductase activity. We used four wild populations of 4-year old J. curcas. The evaluations were conducted every 10 days, between 7 a.m. and 11 a.m. The four populations assessed had the same behavior regarding the leaf senescence, acting uniformly regarding the reactions regulating their development. The photosynthetic activity, chlorophyll content, nitrate reductase activity, vegetative growth and nitrogen content were reduced during senescence. The little variation in day length, appropriate concentration of nitrogen in leaves and high soil water potential throughout the experiment suggest that these variables were not determining to trigger senescence. However, the reduced minimum temperature and the increased thermal range seemed to be determinant for the occurrence of leaf senescence.

Jatropha curcas is a multi-purpose plant species, with many advantages for biodiesel production. Its potential oil productivity is 1.9 t/ha, beginning the fourth year after planting. Nevertheless, limitations such as high harvest cost, lack of scientific konowledge and low profitability have prevented it from being utilized commercially. In order to provide information that could be useful to improve the status of this species as a bioenergy plant, we elucidated the center of origin and the center of domestication of J. curcas (Mexico). Evidence of the antiquity of knowledge of J. curcas by Olmeca people, who lived 3500-5000 years ago, reinforces its Mexican origin. The existence of non-toxic types, which only exist in that country, along with DNA studies, also strongly suggest that Mexico is the domestication center of this species. In Brazil, the Northern region of Minas Gerais State presents types with the highest oil content. Here we propose this region as a secondary center of diversity of J. curcas.

O incremento dos niveis dos gases de efeito estufa, notadamente dioxido de carbono (CO2) na atmosfera terrestre, tem intensificado a busca por combustiveis renovaveis, tipo biodiesel, visando reduzir o consumo de combustiveis fosseis, responsaveis por 40% das emissoes de CO2. Diversas sao as vantagens do uso do biodiesel em comparacao ao diesel de petroleo, dentre elas destacase a sustentabilidade do ecossistema. Neste contexto, a especie Jatropha curcas e uma importante alternativa para producao de biodiesel. Neste trabalho, avaliou-se o efeito da irradiância sobre as caracteristicas fisiologicas de folhas de J. curcas. O experimento foi conduzido em Vicosa (20°45’S, 42°54’W, 650 m de altitude), Minas Gerais, Brasil. Sementes de J. curcas foram semeadas em vasos plasticos de 12 L, contendo uma mistura de 30% de areia e 70% de solo. Metade das mudas foram cultivadas sob telado com 40% da radiacao solar, e a outra metade a pleno sol. A irradiância de satura-cao foi semelhante entre os dois sistemas de cultivo. Entretanto, as plantas cultivadas a pleno sol apresentaram maiores fotossintese, irradiância de compensacao e acumulo de massa seca. Estes resultados sugerem uma relativa aclimatacao da maquinaria fotossintetica de J. curcas a variacao da irradiância.

The study was done with the objective of assessing the genetic diversity existing among Ethiopian and ICARDA barley germplasm using multivariate data analyses. The experiment was conducted at Asasa and Ambo in Ethiopia, in 10 x 10 simple lattices with two replications. To quantify the differentiation among genotypes canonical discriminant analysis, clustering analysis and Mahanalobis (D 2 ) distance were used. The study indicated that the first two canonical variates explained 95% and 91% of the total variation at Asasa and Ambo, respectively. At both the locations, genotypes showed maximum differentiation on days to maturity, grain filling period, tiller per plant and spike per plant. Analysis of clustering grouped the 100 genotypes into four cluster groups at Asasa and six clusters at Ambo. Ethiopian landraces and genotypes from ICARDA grouped in the same cluster groups indicated the germplasm exchange between the Ethiopian and ICARDA barley breeding programs.

Thirty-three coffee SSR primers from enriched genomic library with (GT)15 and (AGG)10 repeats were analyzed in 24 coffee tree accessions. Twenty-two primers were polymorphic among accessions; the number of alleles ranged from 2 to 13, with the mean number of 5.1 alleles per primer. PIC values ranged from 0.08 to 0.79. The highest mean PIC values were found for C. canephora (0.46), and the lowest values for C. arabica (0.22) and triploids (0.22) accessions. The polymorphic SSR markers used in this study were useful for genetic fingerprinting in the coffee tree, especially in the C. canephora and the leaf rust resistant arabica cultivars.

EST-SSR markers were used to investigate the genetic diversity among and within coffee populations, to explore the possibility of their use for fingerprinting of cultivars and to assist breeding programs. Seventeen markers, developed from ESTs (Expressed Sequence Tags) from the Brazilian Coffee Genome Project, were used. All markers showed polymorphism among the genotypes assessed. The average number of allele per primer was 5.1. The highest polymorphisms were found within C. canephora (88.2%) and rust-resistant varieties (35.3%). About 29.4% of the markers differentiated C. arabica from Híbrido de Timor; it was also possible to identify those closest and farthest from C. arabica . The analysis of population-grouped genotypes revealed a 64.0% genetic diversity among and a 36.0% genetic diversity within populations. The differentiation index was 0.637. Six markers distinguished four rust-resistance varieties, showing their fingerprinting potential. These results demonstrate the usefulness of EST-SSR markers for cross orientation, in diversity and introgression studies, and in genetic mapping.

Pinus caribaea var. bahamensis progenies were selected by mixed models using the estimate of the genetic parameters by REML for the prediction of additive genetic values by BLUP. The experimental design was a 11 x 11 partially balanced square lattice containing 119 progenies and two commercial controls. After 13 years, the diameter at breast height (DBH), height and volume were evaluated. The progenies presented good mean performance (18.83 m, 20.80 cm and 0.462 m 3 tree -1 ), and heritability estimates of 0.12, 0.20 and 0.21 for height, DBH and volume, respectively. The trait with greatest variability was the volume w ith a genetic variation coefficient of 22.60% while the genetic variation for height was lower (3.73%). A genetic gain of 14.5% was obtained for DBH with a selection of 250 trees from 56 progenies, with a mean of 4.46 trees selected per progeny and an effecti ve population size of 72.

Coffee is one of the main agrifood commodities traded worldwide. In 2009, coffee accounted for 6.1% of the value of Brazilian agricultural production, generating a revenue of US$6 billion. Despite the importance of coffee production in Brazil, it is supported by a narrow genetic base, with few accessions. Molecular differentiation and diversity of a coffee breeding program were assessed with gSSR and EST-SSR markers. The study comprised 24 coffee accessions according to their genetic origin: arabica accessions (six traditional genotypes of C. arabica), resistant arabica (six leaf rust-resistant C. arabica genotypes with introgression of Híbrido de Timor), robusta (five C. canephora genotypes), Híbrido de Timor (three C. arabica x C. canephora), triploids (three C. arabica x C. racemosa), and racemosa (one C. racemosa). Allele and polymorphism analysis, AMOVA, the Student t-test, Jaccard's dissimilarity coefficient, cluster analysis, correlation of genetic distances, and discriminant analysis, were performed. EST-SSR markers gave 25 exclusive alleles per genetic group, while gSSR showed 47, which will be useful for differentiating accessions and for fingerprinting varieties. The gSSR markers detected a higher percentage of polymorphism among (35% higher on average) and within (42.9% higher on average) the genetic groups, compared to EST-SSR markers. The highest percentage of polymorphism within the genetic groups was found with gSSR markers for robusta (89.2%) and for resistant arabica (39.5%). It was possible to differentiate all genotypes including the arabica-related accessions. Nevertheless, combined use of gSSR and EST-SSR markers is recommended for coffee molecular characterization, because EST-SSRs can provide complementary information.

Jatropha curcas, internationally and locally known, respectively, as physic nut and pinhao manso, is a highly promising species for biodiesel production in Brazil and other countries in the tropics. It is rustic, grows in warm regions and is easily cultivated. These characteristics and high-quality oil yields from the seeds have made this plant a priority for biodiesel programs in Brazil. Consequently, this species merits genetic investigations aimed at improving yields. Some studies have detected genetic variability in accessions in Africa and Asia. We have made the first genetic evaluation of J. curcas collected from Brazil. Our objective was to quantify genetic diversity and to estimate genetic parameters for growth and production traits and seed oil content. We evaluated 75 J. curcas progenies collected from Brazil and three from Cambodia. The mean oil content in the seeds was 31%, ranging from 16 to 45%. No genetic correlation between growth traits and seed oil content was found. However, high coefficients of genetic variation were found for plant height, number of branches, height of branches, and stem diameter. The highest individual narrow-sense heritabilities were found for leaf length (0.35) and width (0.34), stem diameter (0.24) and height of branches (0.21). We used a clustering algorithm to genetically identify the closest and most distant progenies, to assist in the development of new cultivars. Geographical diversity did not necessarily represent the genetic diversity among the accessions collected. These results are important for the continuity of breeding programs, aimed at obtaining cultivars with high grain yield and high oil content in seeds.

O trabalho teve como objetivo avaliar o desenvolvimento de mudas de pupunheira (Bactris gasipaes H.B.K.) cultivadas em amostras de um Latossolo Vermelho eutroférrico de textura argilosa compactado artificialmente em subsuperfície. As amostras de solo que foram compactadas a quatro níveis de densidade (1,0; 1,13; 1,28 e 1,44kg dm-3) estavam nas camadas intermediárias de 3,5cm de vasos de PVC de 20cm de diâmetro, que constavam de outras camadas superiores de 15cm e inferiores de 10cm. As avaliações foram realizadas em quatro épocas (4, 6, 8 e 10 meses). O aumento dos níveis de densidade do solo não influenciou no desenvolvimento da parte aérea das mudas de pupunheira. Independentemente da época estudada, os níveis de densidade do Latossolo argiloso não impediram a penetração das raízes da pupunheira. This study was carried out to evaluate the development of peach palm (Bactris gasipaes H.B.K.) seedlings submitted to artificiality subsurface compacted layers of a clayly texture eutroferric Red Latossol. The compacted soil was at the middle ring of the PVC pots. They were 20cm of diameter, divided in tree rings with 15; 3,5 and 10cm from the up side. The soil was submitted to four density levels (1,0; 1,13; 1,28 and 1,44kg dm-3), which determined the treatments. The evaluations were accomplished in four times (4, 6, 8 and 10 months). The increase of the soil density levels didn't influence in the development of the aerial part of the peach palm seedlings. Independent of the studied time, the clayly Latossol density levels, didn't prevent the peach palm roots penetration.

The main goal of our research was to search for SSRs in the Eucalyptus EST FORESTs database (using a software for mining SSR-motifs). With this objective, we created a database for cataloging Eucalyptus EST-derived SSRs, and developed a bioinformatics tool, named Satellyptus, for finding and analyzing microsatellites in the Eucalyptus EST database. The search for microsatellites in the FORESTs database containing 71,115 Eucalyptus EST sequences (52.09 Mb) revealed 20,530 SSRs in 15,621 ESTs. The SSR abundance detected on the Eucalyptus ESTs database (29% or one microsatellite every four sequences) is considered very high for plants. Amongst the categories of SSR motifs, the dimeric (37%) and trimeric ones (33%) predominated. The AG/CT motif was the most frequent (35.15%) followed by the trimeric CCG/CGG (12.81%). From a random sample of 1,217 sequences, 343 microsatellites in 265 SSR-containing sequences were identified. Approximately 48% of these ESTs containing microsatellites were homologous to proteins with known biological function. Most of the microsatellites detected in Eucalyptus ESTs were positioned at either the 5 or 3 end. Our next priority involves the design of flanking primers for codominant SSR loci, which could lead to the development of a set of microsatellite-based markers suitable for marker-assisted Eucalyptus breeding programs., Genetics and Molecular Biology, 28 (3), ISSN:1415-4757, ISSN:1678-4685

Thirty-three coffee SSR primers from enriched genomic library with (GT)15 and (AGG)10 repeats were analyzed in 24 coffee tree accessions. Twenty-two primers were polymorphic among accessions; the number of alleles ranged from 2 to 13, with the mean number of 5.1 alleles per primer. PIC values ranged from 0.08 to 0.79. The highest mean PIC values were found for C. canephora (0.46), and the lowest values for C. arabica (0.22) and triploids (0.22) accessions. The polymorphic SSR markers used in this study were useful for genetic fingerprinting in the coffee tree, especially in the C. canephora and the leaf rust resistant arabica cultivars.

Made available in DSpace on 2011-04-09T22:28:01Z (GMT). No. of bitstreams: 1 Assessmentofestssr.pdf: 389003 bytes, checksum: f273930646d347b5cc786604c4526c5a (MD5) Previous issue date: 2011-03-10

O objetivo deste trabalho foi estudar o efeito do desbaste seletivo sobre as estimativas de parâmetros genéticos em progênies de Pinus caribaea var. hondurensis. O teste de progênies foi instalado em junho de 1986, seguindo delineamento em látice quadrado 10 x 10, triplo, contendo dez árvores dispostas em parcelas lineares no espaçamento de 3,0 x 3,0m. Aos 12 anos após o plantio foi realizado um desbaste, com intensidade de 40%, tendo por base o Índice Multi-efeito, aplicado ao caráter DAP, deixando-se seis árvores por parcela, em todo o experimento. A coleta de dados foi realizada em quatro situações: A (antes do desbaste), B (árvores desbastadas), C (árvores remanescentes, aos 13 anos) e D (dois anos após o desbaste). Os caracteres analisados foram: altura (ALT), diâmetro à altura do peito (DAP), volume (VOL), forma do fuste (FOR), rabo de raposa (FT) e densidade básica da madeira a 1,3m (DBM1) e na metade da altura da árvore (DBM2). O desbaste seletivo realizado dentro das progênies manteve grande parte da variabilidade genética do teste de progênies. Existe uma alta e positiva correlação genética entre os caracteres de crescimento, principalmente entre DAP e VOL, que se manteve com o desbaste. O desbaste seletivo aumentou a variabilidade genética entre as progênies para VOL e diminuiu para ALT e DAP. As estimativas de herdabilidade em nível individual tiveram um leve aumento, enquanto que em nível de médias houve uma considerável redução com a prática do desbaste seletivo. Os valores genéticos estimados das progênies tiveram considerável aumento com a prática do desbaste, o que pode facilitar na identificação de progênies superiores em futuras práticas de seleção.