ABSTRACT Background: One of the biggest challenges for breeders, especially for perennial plants, is to have strategies to reduce the risk of recommending new clones. One of the alternatives would be to use a mixture of clones, clonal compounds (CC), instead of monoclones (MC). This strategy has not yet been properly proven from experiments involving CC and MC simultaneously in different environments. Results: The CC’s contribution to the interaction was significant, although associated with a high MAI estimate (m³. ha-1. year-1). The CC’s took better advantage of environmental stimuli than most MC’s. The rick estimates in the CC recommendation were, in most situations, lower than those of the different monoclones. Conclusion: The use of CC proved to be more efficient than the use of MC in mitigating the effects of the interaction of genotypes by environments, in recommending clones for forest exploitation.

RESUMO Eugenia dysenterica DC. é uma árvore nativa do Cerrado conhecida como recurso genético por seus frutos e potencial culinário. O conhecimento da variabilidade genética de características agronômicas é importante para subsidiar pesquisas sobre a sua conservação e domesticação. Objetivou-se estimar os parâmetros genéticos quantitativos das características iniciais de crescimento entre e dentro de subpopulações de E. dysenterica, em teste de procedências e progênies, e estabelecer uma coleção de germoplasma representativa da distribuição da espécie. Para isso, 25 subpopulações naturais foram amostradas e, dentro de cada subpopulação, 6 árvores matrizes. As progênies foram semeadas em viveiro, em delineamento de blocos ao acaso constituído de 150 progênies, quatro repetições e cinco plantas por parcela. A análise de variância de caracteres do desenvolvimento inicial revelou maior variabilidade entre progênies dentro da subpopulação do que a observada entre as subpopulações. A biomassa acima do solo representou apenas 15 % da biomassa total, característica recorrente em espécies do Cerrado. A herdabilidade estimada e os coeficientes de variação genética apresentaram potencial de seleção para os caracteres de desenvolvimento inicial, importantes para a produção comercial de mudas. Uma coleção de germoplasma in vivo ex situ foi estabelecida para fins de conservação e melhoramento, utilizando-se uma amostra de quatro plantas de cada progênie.

ABSTRACT Eugenia dysenterica DC. is a native tree from the Brazilian Savanna known as a genetic resource for its fruits and culinary potential. The knowledge on the genetic variability of agronomic traits is important to support studies on its conservation and domestication. This study aimed to estimate the quantitative genetic parameters of initial growth traits among and within E. dysenterica subpopulations, in provenance and progeny testing, and establish a germplasm collection representative of the species distribution. For that, 25 natural subpopulations were sampled and, within each subpopulation, six mother trees. The progenies were sown in a nursery, in a randomized complete blocks design consisting of 150 progenies, four replications and five plants per plot. The analysis of variance of the initial development traits revealed a greater variability among the progenies within the subpopulation than that observed among the subpopulations. The aboveground biomass represented only 15 % of the total biomass, a recurrent characteristic in Brazilian Savanna species. The estimated heritability and coefficients of genetic variation presented selection potential for the initial development traits, which are important for commercial seedlings production. An in vivo ex situ germplasm collection was established for conservation and breeding purposes, using a sample of four plants from each progeny.

Abstract Advances in genotyping technologies have transformed the way breeding programs manage their genetic resources. The identification of single nucleotide polymorphisms (SNPs) can improve understanding of the genetic diversity of maize (Zea mays) inbred lines and their classification into heterotic groups, which is useful in determining certain crosses to obtain hybrids with higher yield performance. The genetic diversity of 293 inbred lines was investigated with 5252 SNPs with minor allele frequency (MAF)>5%. There was an average of 525 SNPs per chromosome. Polymorphism information content (PIC) averaged 0.297. The unweighted pair group method with arithmetic mean analysis (UPGMA) and principal component analysis (PCA) based on the genetic distance matrix revealed four similar clusters and high cophenetic correlation coefficients (0.953 and 0.863, respectively). The results showed consistency between genetic distance-based grouping and the heterotic groups previously established using pedigree and topcross information for the inbred lines studied.

Abstract Eucalyptus plantations in Brazil are expanding toward the northern and mid-western regions of the country. The objective of the present study was to select clones adapted to the local conditions, with a focus on the Cerrado region. Three clonal experiments were conducted in the municipalities of Catalão, Corumbá-de-Goiás, and Luziânia, in Goiás State, with 109 genotypes of eucalypts. The experimental design consisted of a randomized complete block design with single-tree plots and 29 blocks. Diameter at breast height and total height of all trees were measured four years after planting, for use in the estimation of wood volume for each genotype. The genotype × environmental interaction was significant and predominantly (74%) complex. The genotypic correlation among environments was moderate (< 0.47), indicating that clones should be selected for specific sites. However, some clones performed relatively well across all environments, such as clones CCL21, CCL30, AEC144, CCL07, and CCL35.

Abstract Given its high-valued wood, the African mahogany (Khaya grandifoliola) has been envisaged as a renewable source of tropical hardwoods in Brazil. However, there are concerns about the hypothesized low diversity among the few K. grandifoliola germplasm sources introduced in the country. Using eight microsatellite markers, we evaluated the genetic diversity and divergence among 53 superior trees selected from three provenances of K. grandifoliola located in the state of Para. These populations are among the oldest plantations (>15 years) in Brazil and, therefore, the country's main seed sources. The average number of alleles per locus was 5.9, expected heterozygosity was moderate (^=0.56) and lower than the high observed heterozygosity (HO=0.74). Therefore, the intrapopulation fixation index was negative (f=-0.31) indicating the possibility that selection of superior trees might have favored heterozygous plants with heterosis. No genetic structure was observed between provenances. The genetic diversity observed within selected trees, with an effective population size (Ne) of 30.4, is comparable to that of natural populations of African and Brazilian mahoganies. Therefore, our results contradict the idea that the genetic diversity of K. grandifoliola introduced in Brazil is low and show that our germplasm can be exploited for breeding purposes.

ABSTRACT: Despite important biotic stresses to common bean, Anthracnose (ANT) and Angular Leaf Spot (ALS) can cause losses of up to 80 % and occur in more than 60 countries around the world. Genetic resistance is the most sustainable strategy to manage these diseases. Thus, we aimed to (1) identify new SNP markers associated with ALS and ANT resistance loci in elite common bean lines, and (2) provide a functional characterization of the DNA sequences containing the identified SNP markers. We evaluated 60 inbred lines, under field conditions, which represent the elite germplasm developed by the Embrapa common bean breeding program across 22 years, in terms of severity of the ALS and ANT. The lines were genotyped with 5,398 SNPs. Then, a Mixed Linear Model was run to determine the SNP-trait associations. We observed two-significant marker-trait associations reacting to ANT, both located on chromosome Pv-02. These markers explained 25 % of the phenotypic variation. For ALS, only one significant marker-trait association was observed, which is located in chromosome Pv-10 and explained 19 % of the phenotypic variation. These markers, along with others already used, will be useful to add or keep ANT and ALS resistance loci identified in this work in the new carioca and black seeded cultivars.

Abstract Eukaryotic cells have different mechanisms of post-transcriptional regulation. Among these mechanisms, microRNAs promote regulation of targets by cleavage or degradation of the mRNA. Fungi of the Paracoccidioides complex are the etiological agents of the main systemic mycosis of Latin America. These fungi present a plasticity to adapt and survive in different conditions, and the presence of microRNAs-like molecules could be part of the mechanisms that provide such plasticity. MicroRNAs produced by the host influence the progression of this mycosis in the lungs besides regulating targets involved in apoptosis in macrophage, activation of T and B cells and the production of cytokines. Therefore, this work analyzed the presence of regions in the genome of this fungus with a potential to encode microRNAs-like molecules. Here we show by analysis of sequence similarity the presence of 18 regions, putatively coding for microRNAs-like molecules in the Paracoccidioides brasiliensis genome. We also described the conservation of dicer and argonaut proteins and the cognate transcripts induced in the yeast parasitic phase. This work represents a starting point for the analysis of the presence of those molecules in the morphological stages of the fungus and their role in fungal development.

Resumo Eugenia dysenterica DC. (cagaiteira) é uma árvore frutífera nativa do Cerrado brasileiro. É uma espécie promissora para cultivo, mas que carece de informações básicas sobre diversidade fenotípica e variação quantitativa de seus frutos e sementes em escala populacional. Neste contexto, o presente estudo propõe estimar parâmetros fenotípicos de frutos e de sementes da espécie, a partir da variabilidade entre matrizes e subpopulações, visando a ampliar o conhecimento para o melhoramento e a conservação da espécie. Para isso, foram amostradas 25 subpopulações (populações locais) naturais, em cinco estados brasileiros. Dentro de cada subpopulação, foram coletados 20 frutos de cada uma das seis matrizes amostradas. Dados de massa, comprimento transversal e longitudinal dos frutos e sementes foram submetidos à análise descritiva, correlações e análise de variância, por um modelo hierárquico. Houve variação significativa entre matrizes dentro de subpopulações e entre subpopulações, com altos níveis de variação fenotípica. As altas variações e a formação de grupos divergentes fenotipicamente são importantes elementos para o pré-melhoramento da cagaiteira, cujas matrizes já podem ser selecionadas para os caracteres estudados. A divergência fenotípica entre populações (PST) pode ser utilizada como um indicador da estruturação da variação fenotípica da espécie em sua área natural de ocorrência.

Abstract Eugenia dysenterica DC. (cagaita tree) is a fruit tree native to the Brazilian Cerrado. It is a promising species for cultivation, but little basic information exists on the phenotypic diversity and quantitative variation of its fruits and seeds at a population scale. Thus, the present study proposes to estimate the phenotypic parameters of the species’ fruits and seeds based on the variability among mother plants and among subpopulations, thereby aiming to increase knowledge for breeding and conservation of the species. For this, 25 natural subpopulations (local populations) were sampled in five Brazilian states. Within each subpopulation, 20 fruits were collected from each of six sampled mother plants. Data for biomass, transverse and longitudinal lengths of the fruits and seeds were subjected to estimates of descriptive parameters, correlation and hierarchical analysis of variance (ANOVA). Significant variation, including high levels of phenotypic variation, was observed among mother plants within the subpopulations and between the subpopulations. The high variation and the formation of phenotypically divergent groups are important elements for the breeding of cagaita tree, whose mother plants can now be selected for the traits studied. Phenotypic divergence between populations (PST) can be used as an indicator of the structuring of the phenotypic variation of the species in its natural area of occurrence.

Resumo: No artigo são exploradas as possibilidades de desenvolvimento dos territórios rurais brasileiros mais pobres. São analisadas as condições de vida dos agricultores locais entrevistados em 7.975 domicílios rurais de 37 territórios de todo o país. Enquanto cerca de 80% dos agricultores revelam ter ativos disponíveis para a produção agropecuária, apenas 20% têm boas condições de comercialização e acesso às políticas agrícolas.

Abstract: This study explores the possibilities for development in poor Brazilian rural territories. It assesses the livelihoods of local farmers interviewed in 7,975 households in 37 different territories across the country. While 80% of farmers have potential for production in their farms, only 20% have good access to markets and agricultural policies.

Resumen: Este estudio explora las posibilidades de desarrollo local en los territorios rurales brasileños pobres. Se basa en la evaluación de los medios de vida de los campesinos entrevistados en 7.975 hogares en 37 territorios en todo el país. Mientras que el 80% de los agricultores tienen algún potencial de producción, sólo el 20% tienen un buen acceso a los mercados y las políticas agrícolas.

Résumé: Cette étude explore les possibilités de développement dans les territoires ruraux brésiliens pauvres. Il est basé sur les moyens d'existence des agriculteurs locaux interrogés dans 7.975 ménages dans 37 territoires différents à travers le pays. Alors que 80% des agriculteurs ont un certain potentiel de production, seulement 20% ont un bon accès aux marchés et les politiques agricoles.

O trabalho traz a percepção dos agricultores familiares brasileiros sobre suas condições de vida a partir de entrevistas realizadas em 10.362 domicílios rurais em todas as regiões do país. Os agricultores percebem de forma positiva as condições de produção dentro da propriedade (incluindo área utilizada e mão de obra existente) e de forma negativa os resultados alcançados da porteira para fora (acesso a políticas públicas, inserção em mercados e relações sociais).

This paper presents the Brazilian family farmers’ perception on their livelihoods based on interviews carried out with 10.362 farmers all over the country. The results reveals a positive perception family farmers have on their in-farm conditions for production (including land and labor availability) and a negative perception on their performance out of the farm (including access to public policies, markets and social relationships).

Este artículo muestra la percepción de los campesinos brasileños acerca de sus condiciones de vida desde encuestas hechas en 10362 domicilios rurales en todas las regiónes del país. Los campesinos observan de forma positiva las condiciones de produción dentro de la propriedad (incluyendo área utilizada y mano de obra disponíble) y de forma negativa los resultados alcanzados fuera de la propiedad (insersión hacia los mercados, aceso a políticas públicas y relaciones sociales).

Cette étude présente le perception des agriculteurs familiaux au Brésil sur leurs conditions de vie à partir des interviews menées dans 10.362 ménages ruraux dans toutes les régions du pays. Les agriculteurs perçoivent positivement les conditions de production au sein de la propriété (zone utilisée et la main-d’oeuvre existante) et négativement les résultats obtenus dehors la propriété (marchés d’insertion, l’accès aux politiques publiques et à la vie sociale).