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To increase yield, breeding programs must search for innovative and efficient methodologies for the development and selection of superior genotypes. Therefore, this study aimed to compare the single- and multiple-trait best linear unbiased prediction (BLUP) in genetic selection of parents and hybrids of grain sorghum. For this, an experiment conducted in alpha-lattice design with two replications was used. Flowering time (FT), plant height (PH), and grain yield (GY) were evaluated in 502 grain sorghum hybrids obtained by the cross of ten restorer lines and 54 male-sterile lines. Variance components were estimated via restricted maximum likelihood (REML). Significant effects of restorer lines, of male-sterile lines, and of specific combining ability were detected by the likelihood ratio test (LRT). The estimates of variance components, genetic parameters, and correlations were similar when obtained via single- and multiple trait- BLUP. Considering hybrids, the multiple-trait BLUP resulted in slightly higher predicted selection gain for the three evaluated traits and, therefore, can be efficiently applied in the genetic selection of grain sorghum.

The objectives of this study were to estimate the general and specific combining ability of the parents, and to verify the existence of maternal effect and inbreeding depression in Jatropha. The experiment was carried out from 2010 to 2015, in the municipality of Planaltina, Distrito Federal. The following traits were evaluated: plant height, stem diameter, canopy projection between the row, canopy projection on the row, number of branches, mass of one hundred grains, and grain yield. Cytoplasmic effects and effects of female parent nuclear genes were observed for all traits. Dominance effects were predominant in the genetic control of all traits. Genotypes 107 and 190 were the superior parents for the reduction of the size, and for the increase of grain yield. No inbreeding depression was observed for grain yield. The most promising crosses for the conduction of segregating populations and increment in grain yield were 190x107, 107x190 and 259x107.

Rbio is a free software for data processing. It is compatible and integrated with the free R software, which is globally accepted for statistical analysis. Thus, Rbio takes advantage of all processing potential of the R software. However, this new software allows the user to perform all the analyses without knowing the programming in R language. Rbio is available in Portuguese; it can be downloaded from the Internet (http://www.biometria.ufv.br), and requires the Windows operating system. It has a set of sample files, making it easy to be used. Currently, it supplies the user with all scripts internally used to process the analyses. Rbio can perform descriptive statistics, analysis of variance, estimation of genetic parameters and means tests, multivariate analysis, nonparametric tests, regressions, correlations, biometrics, bioinformatics, and simulation.

The objective of this study was to evaluate three systems of seedling production of interspecific hybrids of American oil palm and African oil palm (HIE), difference between 12 sib progenies of BRS Manicoré cultivar and the interaction between these two factors. The production systems were evaluated: (i) two- stage nursery with the initial shading (conventional system), (ii) two-stage nursery without shading and (iii) one-stage nursery without shading. The variables evaluated were plant height, number of leaves and stem diameter at 106, 191 and 393 days after sowing. In all variables and periods analyzed, the genotype and environmental factors were significant to F test, but the interaction genotype x environment was not significant. The best development of seedlings in the nursery production system occurred in one-step nursery without shading. The two stages nursery with shading in pre-nursery, which is currently the most widely adopted, resulted in lower seedling development.

Cowpea is a legume of great importance in the Brazilian nutrition, mainly in the Northeast region. Despite the low yield of Brazilian cowpea, the species presents a genetic potential to be explored. Thus, this work aimed to characterize the genetic diversity of cowpea genotypes by agronomic traits and select genotypes for possible crosses by multivariate analysis. Four value for cultivation and use tests were carried out with cowpea genotypes in 2005 and 2006, in the municipalities of Aquidauana, Chapadão do Sul, and Dourados, in the state of Mato Grosso do Sul. The experimental design was a complete randomized block with 20 genotypes and four replications. The evaluated traits were value for cultivation, plant lodging, pod length, grain weight of five pods, number of grains per pod, pod weight, severity of powdery mildew, and grain yield. To estimate the genetic diversity among the genotypes, the optimization methods of Tocher and UPGMA were used. The generalized distance of Mahalanobis was used as a dissimilarity measure. The clustering methods revealed genetic variability among the cowpea genotypes evaluated. The methods used formed a different number of groups for each environment. Genotypes TE97-309G-24, MNC99-542F-5, BRS Paraguaçu, BRS Paraguaçu, BR 17-Gurguéia, and CNC x 409-11F-P2 can be used to obtain promising combinations and high genetic variability.

The objective of this work was to estimate the general combining ability of partially inbred lines under high and low nitrogen (N) conditions and to select promising lines to obtain high yields for both conditions. Fifty-five partially inbred S1 progenies were evaluated using the top-cross method, where the lines were crossed with two testers. The 110 top-cross hybrids were evaluated for grain yield during the off-season of 2012 at two sites in the Brazilian Midwest. Partial diallel analysis was performed with the adjusted means of each of the individual analyses of the top crosses. The combining ability of partially inbred lines and testers as well as their interaction with N levels, was estimated for each site. The coefficient of concordance among 15 partially inbred lines selected by the highest general combining ability estimates for each N level was 0.60. The S1 lines 39, 11, 41, 55, 38, 37, 6, 8, and 14 were selected at both N levels. This indicates that these lines can be used to identify ideal hybrids for growing in the off-season in the Brazilian Midwest.

O objetivo do trabalho foi avaliar o consumo e a digestibilidade aparente por ovinos, consumindo silagem de milho e diferentes proteinados. Foram utilizadas cinco ovelhas adultas, da raça Santa Inês, não gestantes, dispostas em um delineado em quadrado latino 5X5, submetidas à cinco tratamentos: farelo de soja + gordura protegida de palma; farelo de soja; farelo de soja protegido; farelo de soja protegido + gordura protegida de palma e farelo de soja protegido + gordura protegida de soja. Foram avaliados os consumos de matéria seca (MS), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), de água e proteinado e a digestibilidades referentes à MS, PB e FDN. Os dados foram analisados usando o teste estatístico Student-Newman-Keuls com significância de 5%. Os tratamentos não afetaram consumo e a digestibilidade dos animais (P>0,05), somente o consumo de água (P

The goal of this work was to compare the effect of the accuracy and residual variance in genome wide selection using marker selection as well as using the effect of the indirect selection, using simulated and real data. In simulated data was used one sample with 200 individuals with 1,000 molecular markers in F2 population. The real data was obtained in maize with F2 population with 441 individuals and genotyping with 261 SSR markers. There was 11 traits evaluated (ear length, ear width, row number, kernels per row, 100-kernel weight, ear weight, grain yield, length of branch, number of branch, plant height and ear height). All data was analyzed using rrBLUP method and 10-fold cross-validation. In simulated and maize data the results were similar: the residual variance with few markers is lower than with the 1000 markers and the accuracy with few markers is bigger than with 1000 markers. For maize data multi trait selection, the accuracy increased when the correlation between traits is greater than 0.50 and residual variance decreased when the correlation is greater than 0.70. In this sense, these results showed that marker selection could be used as a first step in genome wide selection, improving the prediction and compute demand.

Environmental stratification studies are important for the plant breeding, since they allow to adequately plan the experimental network. The objective of this work was to identify similar environments for cotton cultivation in the Brazilian Cerrado regarding yield and fiber quality. Nineteen field studies were carried out in a randomized complete block design with twelve genotypes and four replicates. Agronomic (cotton seed yield and fiber percentage) and technological traits (length, micronaire, fiber strength) were evaluated. These results indicate that there are six environments (PVA3, MON, SHE1, SIN, PPA e TRIN) in which the cotton trials should be installed as a matter of priority owing to the phenotypic response pattern obtained for the evaluated traits. The remaining 13 environments are similar to each other for all traits and can be summarized in strategic locations depending on the ease of installation of the trials.

Photosynthetic efficiency has become the target of several breeding programs since the positive correlation between photosynthetic rate and yield in soybean suggests that the improvement of photosynthetic efficiency may be a promising target for new yield gains. However, studies on combining ability of soybean genotypes for physiological traits are still scarce in the literature. The objective of this study was to estimate the combining ability of soybean genotypes based on F2 generation aiming to identify superior parents and segregating populations for physiological traits. Twenty-eight F2 populations resulting from partial diallel crossings between eleven lines were evaluated in two crop seasons for the physiological traits: photosynthesis, stomatal conductance, internal CO2 concentration, and transpiration. General combining ability (GCA) of the parents and specific combining ability (SCA) of the F2 populations were estimated. Our findings reveal the predominance of additive effects in controlling the traits. The genotype TMG 7062 IPRO is the most promising parent for programs aiming at photosynthetic efficiency. We have also identified other promising parents and proposed cross-breeding with higher potential for obtaining superior lines for photosynthetic efficiency.

ABSTRACT: Forest breeding is a science that has been developing in Brazil since 1941 being the Eucalyptus a highlighted genus in this scenario. In a global scene, Brazil is displayed prominently in productivity of Eucalyptus planting, due to favorable environmental conditions to cultivation development, and the incentive in research for improvement of traits of interest t observed in it species and hybrids. This research included a historical review of Eucalyptus breeding over the years under genetic biometric perspective in Brazil, from reports describing the pioneer planting up to the current genome wide selection (GWS) that came as a complement of forest breeding success. This review showed some of the tracks performed by researchers aiming to improve the productive and quality of phenotypic traits from Eucalyptus genus.

It is essential that concepts surrounding species interactions and their importance for biodiversity conservation are widely taught and understood. Incorporating playfulness into ecological education initiatives can attract more interest in these aspects of ecology. Over the last three decades Pokémon has engaged with millions of people by replicating many aspects of real-world wildlife in cartoons and games. Studies have speculated how the Pokémon franchise creates opportunities for didactic purposes. This study aims to identify the potential for ecological interactions portrayed in the Pokémon universe to contribute to children's engagement and learning. We first gathered information on all the ecological interactions described among Pokémon 'species' from the franchise's website. We found 150 Pokémon species engaging in an array of different ecological interactions. We tested the use of Pokémon as a teaching tool about ecological interactions to high-school students aged [greater than or equal to] 18 years. The use of Pokémon significantly increased learning of almost half of ecological interactions and raised engagement, particularly among students who like the franchise. Our findings show that Pokémon can be a playful and didactic tool for teaching about ecological interactions.

Fiber length stands out among technological traits as one that still needs to be improved in cotton. Thus, the objectives of this work were to quantify the interrelations between agronomic and technological fiber traits and to identify traits that could be used for the indirect selection of cotton genotypes with longer fiber lengths. Agronomic and technological traits were evaluated in 36 elite lines of cotton that were cultivated in three environments. Canonical correlations were estimated between two groups of traits: agronomic and technological. Path analysis was performed that considered fiber length as the primary dependent variable. The genotypes presented variability in all the evaluated traits, and no significant genotype vs. environmental interaction was observed for any of them. The main technological traits of cotton crops can be improved by an indirect selection of agronomic traits. The selection of cotton genotypes with a smaller size and a higher mean boll weight can be used to increase fiber length and improve other technological traits. Selection indices containing plant height, mean boll weight, fiber strength, and fiber uniformity can be one of the main strategies for the selection of cotton genotypes with a high yield of cotton bolls and long fibers.

Diallel crosses in an unbalanced scheme were carried out in Jatropha to (i) evaluate the additive and non-additive genetic components; (ii) select parents through the general combining ability; (iii) estimate the specific combining ability used in the crosses; and (iv) verify the existence of the maternal effect and inbreeding depression. The experiment was carried out in a complete diallel scheme with four progenitors, unbalanced for the number of crosses. The experimental design consisted of a randomized block, with 5 replications and 3 plants per plot. The following characteristics were evaluated: stem diameter (SD), number of branches (NB), plant height (PH), canopy projection on the row (CPR), canopy projection between rows (CPB), mass of hundred grains (MHG) and grain yield (GY). Estimates of variances were obtained using the method of restricted maximum likelihood, while breeding values were estimated by the best linear unbiased prediction. It was concluded that the additive effect was predominant in the genetic control for SD, CPR, and CPB; the dominance effect was predominant for PH, NB, and GY; there was a cytoplasmic effect and nuclear genes of the female parent for all evaluated traits; parents 107 and 190 are promising for reducing the size and increasing the grain yield; there was inbreeding depression for SD and GY; and the favorable crosses for increasing GY were 190x107 and 190x190.

[This corrects the article DOI: 10.1371/journal.pone.0192189.].

Asian rust affects the physiology of soybean plants and causes losses in yield. Repeatability coefficients may help breeders to know how many measurements are needed to obtain a suitable reliability for a target trait. Therefore, the objectives of this study were to determine the repeatability coefficients of 14 traits in soybean plants inoculated with Phakopsora pachyrhizi and to establish the minimum number of measurements needed to predict the breeding value with high accuracy. Experiments were performed in a 3x2 factorial arrangement with three treatments and two inoculations in a random block design. Repeatability coefficients, coefficients of determination and number of measurements needed to obtain a certain reliability were estimated using ANOVA, principal component analysis based on the covariance matrix and the correlation matrix, structural analysis and mixed model. It was observed that the principal component analysis based on the covariance matrix out-performed other methods for almost all traits. Significant differences were observed for all traits except internal CO2 concentration for the treatment effects. For the measurement effects, all traits were significantly different. In addition, significant differences were found for all Treatment x Measurement interaction traits except coumestrol, chitinase and chlorophyll content. Six measurements were suitable to obtain a coefficient of determination higher than 0.7 for all traits based on principal component analysis. The information obtained from this research will help breeders and physiologists determine exactly how many measurements are needed to evaluate each trait in soybean plants infected by P. pachyrhizi with a desirable reliability.

Jatropha (Jatropha curcas) has become one of the most important species for producing biofuels. Currently, Genotype x Environment (GxE) interaction is the biggest challenge that breeders should solve to increase the section accuracy in the plant breeding. Therefore, the objectives in this study were to estimate the parameters in the 180 half-sib families in Jatropha evaluated for five production years, to verify the significance of the GxE interaction variance, to evaluate the adaptability and stability for each family based on three prediction methods, to select superior half-sib families based on the adaptability and stability analyses, and to predict the accuracy for the sixth production year. Jatropha half-sib families were classified and selected using the follow adaptability and stability methods: linear regression, bi-segmented linear regression and mixed models concepts called harmonic mean of the relative performance of genetic values (HMRPGV). The prediction accuracy was estimated by the Pearson correlation between the predicted genetic values by adaptability and stability methods and the phenotypic value in the sixth production year. In result, most half-sib families were classified as general adaptability and general stability for the evaluated traits. The selection gain obtained via HMRPGV was higher than other methods. The prediction accuracy for the sixth production year was 0.45. Therefore, HMRPGV is efficient to maximize the genetic gain, and it can be a useful strategy to select genotype with high adaptability and stability in Jatropha breeding as well as other species that should be evaluated for many years to take a suitable selection accuracy.

This study aimed to estimate the genetic diversity among soursop genotypes in terms of fruit yield evaluated in different crop years. Sixteen measurements for fruit yield in 71 soursop genotypes were carried out from 2000 to 2016. Based on ANOVA it was verified the existence of genetic variability among genotypes in the different measurements (harvests). The genotypes were clustered according to their respective fruit yield averages in the 16 years as well as from their means obtained in each measurement year by the Scott-Knott test (p

Developing strawberry cultivars that can be grown on a large scale, it is necessary to gather desirable characteristics such as: tolerance to Tetranychus urticae, high fruit yield and wide adaptability to several cropping managements. Therefore, our objective was to study the genetic diversity among 13 strawberry cultivars under different managements and to recommend promising crosses to obtain segreganting populations with high fruit yield and T. urticae tolerance. Trial was performed under field conditions at the Centro Regional de Desenvolvimento Rural Centro Serrano of the Instituto Capixaba for Technical Assistance and Rural Extension (Incaper), Domingos Martins-ES. We evaluated strawberry cultivars Albion, Aleluia, Aromas, Camarosa, Camino Real, Campinas, Diamante, Dover, Festival, Seascape, Toyonoka, Tudla, and Ventana, cultivated in three cropping managements: open field, low tunnel and high tunnel. Experimental design was randomized complete blocks with three replications. Variables evaluated were: number of two-spotted spider mite/cm2 on the leaf (NTSSM), total number of fruits (TNF), number of commercial fruits (NCF) and fruit yield (YIE, t/ha). We applied the generalized Mahalanobis distance and Tocher's optimization method to study the genetic diversity among cultivars in each management, and the relative contribution of traits to genetic diversity was evaluated according to the criterion described by Singh (1981). For the low tunnel and high tunnel environments, the crosses Aleluia x Camarosa, Aleluia x Aromas and Aleluia x Festival are the most promising to generate segregating populations with a higher possibility to appearance transgressive individuals, while for the open field cultivation system, we recommend the cross among Aleluia x Toynoka. The variables that most contributed for genetic dissimilarity were total number of fruits, fruit yield and number of commercial fruits for the environments open field, low tunnel and high tunnel, respectively.

Field experiment should be carried out with high accuracy since the discarding of a trial involves waste of time and resources, and can mislead breeders in selecting inferior genotypes. The simulation of a large number of experiments with great variability of traits is the main strategy to assist breeders on how to perform the experiment. Therefore, the objective of this study was to evaluate two criteria to infer the experimental quality: Coefficient of Variation (CV) and repeatability coefficient. Experimental data from evaluations of common bean lines carried out in 104 experiments were used in this study. The simulation of the scenarios used the following parameters: number of cultivars, number of blocks, genetic variance, mean yield, and coefficient of variation. Two thousand replications for each scenario were simulated. Genotypes means were arranged in an order, and the Spearman correlation was obtained between the estimated genotypes mean and the true genotypic values. Results revealed that CV is not a reliable parameter to evaluate the quality of experiment in the field. In conclusion, repeatability coefficient is the parameter that defines the discarding criteria of evaluation experiments and the recommendation of cultivars, as long as the values for each response variable are established.

The aim of this study was to evaluate the methodology of Artificial Neural Networks (ANN) in order to predict wood volume in eucalyptus and its impacts on the selection of superior families, and to compare artificial neural network with regression models. Data used were obtained in a random block design with 140 half-sib families with five replications at three years of age, and four replications at six years of age, both with five plants per plot. The volume was estimated using ANN and regression models. It was used 2000 and 1500 data to train ANN, and 1500 and 1300 to validate ANN for 3 and 6 years of age, respectively. It is concluded that ANN can help improving the accuracy to measure the volume in eucalyptus trees, and to automate the process of forestry inventory and were more accurate in predicting wood volume than almost all regression models.

The objective of this work was to select families with superior performance and large genetic variability for diallel crosses for potential use in the pre-breeding of oil palm. The experiment consisted of 42 full-sib families divided into three trials with 16 families and 3 witnesses in common in randomized blocks, with four blocks and 12 plants per block. The characteristics evaluated in the experiment were number of bunches per plant (NBP), bunch weight per plant (BWP) and bunch average weight per plant (BAW). The estimation of variance components showed that there was greater genetic variance within families than between families. The heritability for all traits was high, above 0.75, and the coefficient of environmental variation was low to moderate for all traits (between 4 and 13). Tocher’s method separated families into seven groups, whereas the UPGMA method identified six groups. To use the best families in diallel crosses, families 15, 14, 22, 21, 28, 37, 33 and 39 were selected based on individual performance as determined by the Scott-Knott test and genetic diversity by grouping.

O objetivo deste trabalho foi desenvolver e validar uma metodologia de análise da adaptabilidade e da estabilidade fenotípica baseada em regressão quantílica (RQ). Para tanto, foram simulados valores fenotípicos com distribuição simétrica e com distribuição assimétrica à direita e à esquerda, com ou sem a presença de "outliers". A metodologia proposta foi aplicada a um conjunto de dados provenientes de um experimento com 92 genótipos de alfafa (Medicago sativa), avaliados em 20 ambientes, e comparada às metodologias de Eberhart & Russell e de regressão não paramétrica. A metodologia da RQ proporcionou resultados iguais ou superiores aos obtidos com as metodologias alternativas avaliadas. No entanto, a ocorrência de resultados discordantes entre as metodologias evidencia a importância de se avaliar a simetria na distribuição dos valores fenotípicos. Para distribuições simétricas, na presença de "outliers", deve-se utilizar a RQ com valor de quantil estimado (τ) em 0,50; na ausência de "outliers", pode-se utilizar tanto a metodologia de Eberhart & Russell quanto a RQ (τ = 0,50). Para distribuições assimétricas, indica-se o uso da RQ com τ = 0,25, para assimetria à direita, e com τ = 0,75, para assimetria à esquerda, independentemente da presença de "outliers".

Analysis using Artificial Neural Networks has been described as an approach in the decision-making process that, although incipient, has been reported as presenting high potential for use in animal and plant breeding. In this study, we introduce the procedure of using the expanded data set for training the network. Wealso proposed using statistical parameters to estimate the breeding value of genotypes in simulated scenarios, in addition to the mean phenotypic value in a feed-forward back propagation multilayer perceptron network. After evaluating artificial neural network configurations, our results showed its superiority to estimates based on linear models, as well as its applicability in the genetic value prediction process. The results further indicated the good generalization performance of the neural network model in several additional validation experiments.

Genomic wide selection is a promising approach for improving the selection accuracy in plant breeding, particularly in species with long life cycles, such as Jatropha. Therefore, the objectives of this study were to estimate the genetic parameters for grain yield (GY) and the weight of 100 seeds (W100S) using restricted maximum likelihood (REML); to compare the performance of GWS methods to predict GY and W100S; and to estimate how many markers are needed to train the GWS model to obtain the maximum accuracy. Eight GWS models were compared in terms of predictive ability. The impact that the marker density had on the predictive ability was investigated using a varying number of markers, from 2 to 1,248. Because the genetic variance between evaluated genotypes was significant, it was possible to obtain selection gain. All of the GWS methods tested in this study can be used to predict GY and W100S in Jatropha. A training model fitted using 1,000 and 800 markers is sufficient to capture the maximum genetic variance and, consequently, maximum prediction ability of GY and W100S, respectively. This study demonstrated the applicability of genome-wide prediction to identify useful genetic sources of GY and W100S for Jatropha breeding. Further research is needed to confirm the applicability of the proposed approach to other complex traits.

O camucamuzeiro pertence à família Myrtaceae e é espécie em processo de domesticação, encontrada na forma extrativa, a partir de plantas crescendo naturalmente nas margens dos rios e lagos, ou cultivadas em pequenas áreas de terra firme. As estimativas e a compreensão dos parâmetros genéticos desta espécie são importantes para o conhecimento da estrutura genética das populações e para a inferência da diversidade genética presente, além de proporcionar subsídios para predizer os ganhos genéticos e o possível sucesso no programa de melhoramento dessa cultura. Neste sentido, o objetivo deste trabalho foi estimar parâmetros genéticos e a dissimilaridade genética, em acessos existentes no Banco Ativo de Germoplasma de camucamuzeiro, da Embrapa Amazônia Oriental. Para o estudo, foram analisados 46 progênies, colhidos 40 frutos por planta matriz em completo estádio de maturação (frutos com epicarpo totalmente roxo), sendo avaliados sete caracteres morfoagronômicos: peso de fruto (g, PFR), comprimento de fruto (cm, CFR), diâmetro de fruto (cm, DFR), peso da casca (g, PCS), espessura da casca (cm, ECS), número de sementes (n, NSE), peso de sementes (g, PSE). Por meio do Programa Genes, estimaram-se os componentes de variância, herdabilidade e a variabilidade. A importância relativa de caracteres e dissimilaridades entre as progênies, bem como as correlações genéticas entres os caracteres avaliados também foram estudadas. Verificou-se que há dissimilaridade entre os acessos do BAG de camucamuzeiro e que, por causa das correlações significativas entre as variáveis, podem-se adotar métodos de seleção indireta como ferramenta auxiliar no processo de domesticação e melhoramento desta espécie.

There is substantial controversy about the addictive potential of modafinil, a wake-promoting drug used to treat narcolepsy, proposed as pharmacotherapy for cocaine abuse, and used indiscriminately by healthy individuals due to its positive effects on arousal and cognition. The rapid-onset type of behavioral sensitization (i.e., a type of sensitization that develops within a few hours from the drug priming administration) has been emerged as a valuable tool to study binge-like patterns of drug abuse and the neuroplastic changes that occur quickly after drug administration that ultimately lead to drug abuse. Our aim was to investigate the possible development of rapid-onset behavioral sensitization to modafinil and bidirectional rapid-onset cross-sensitization with cocaine in male Swiss mice. A priming injection of a high dose of modafinil (64 mg/kg) induced rapid-onset behavioral sensitization to challenge injections of modafinil at the doses of 16 mg/kg, 32 mg/kg, and 64 mg/kg, administered 4h later. Furthermore, rapid-onset cross-sensitization was developed between modafinil and cocaine (64 mg/kg modafinil and 20 mg/kg cocaine), in a bidirectional way. These results were not due to residual levels of modafinil as the behavioral effects of the priming injection of modafinil were no longer present and modafinil plasma concentration was reduced at 4h post-administration. Taken together, the present findings provide preclinical evidence that modafinil can be reinforcing per se and can enhance the reinforcing effects of stimulants like cocaine within hours after administration.

The origin and evolution of Bambuí Basin has been a matter of debate, in much intensified by the recent exploratory efforts carried out by public and private companies looking for natural gas. In the southeastern portion of the basin there are rare opportunities to access the contact between the sedimentary rocks and its basement, whose characteristics are crucial to understanding the processes of basin installation and the early sedimentation. The analysis of drill cores allowed us to describe the lowermost Bambuí Group in Arcos (MG) region, including its basement. The sampled section displays as basement an archean granodiorite (ca. 2.8 – 2.9 Ga), fractured at the time of sedimentation. The Bambuí Group basal unit is dm-thick, massive lodgment tillite. Grains of zircon separated from the tillite matrix were dated and show a main age peak at ca. 2.8 Ga, indicating provenance from the own basement. On the tillite rests an impure limestone that passes gradually to a muddy unit, in a retrogradational filling trend. Terrigenous fragments in the impure limestone suggests that the basement has continued to be a source of sediments in the bottom of the section. The pelitic rocks that occurs to the top has a litochemical signature compatible with acidic source rocks, and shows Sm-Nd model ages of 1.7 Ga. These data suggests that rocks from the Brasília Belt have acted as a source for the pelitic rocks, supporting the interpretation of a foreland set for the basin.

The Information Technology (IT) has undergone profound and rapid changes in recent decades. In this context, organizations must be prepared to implement these technologies, on the form of projects, as quickly and effectively as possible, providing results before its competitors. Therefore, it can be noted that the delivery of a project on time, ever shorter, is essential. Considering these observations, the main purpose of this study is to explore how failures in IT project stakeholder management may impact, directly or indirectly, the deadlines of these projects. The empirical research, qualitative in nature, is of the exploratory type and counted with the participation of IT project managers and managers of IT project managers, who answered a semi structured interview and provided documents in support of the research. The transcripts of the interviews as well as the provided documents were used for the analysis of data content. As a final result of this study, the main failures in the stakeholder management that may compromise – mostly indirectly – the timely delivery of IT projects are identified and explored.

The purpose of this work was to evaluate a methodology of adaptability and phenotypic stability of alfalfa genotypes basedon the training of an artificial neural network considering the methodology of Eberhart and Russell. Data from an experiment on drymatter production of 92 alfalfa genotypes (Medicago sativa L.) were used. The experimental design constituted of randomized blocks,with two repetitions. The genotypes were submitted to 20 cuttings, in the growing season of November 2004 to June 2006. Each cuttingwas considered an environment. The artificial neural network was able to satisfactorily classify the genotypes. In addition, the analysispresented high agreement rates, compared with the results obtained by the methodology of Eberhart and Russell.

The genetic variability of the Brazilian physic nut (Jatropha curcas) germplasm bank (117 accessions) was assessed using a combination of phenotypic and molecular data. The joint dissimilarity matrix showed moderate correlation with the original matrices of phenotypic and molecular data. However, the correlation between the phenotypic dissimilarity matrix and the genotypic dissimilarity matrix was low. This finding indicated that molecular markers (RAPD and SSR) did not adequately sample the genomic regions that were relevant for phenotypic differentiation of the accessions. The dissimilarity values of the joint dissimilarity matrix were used to measure phenotypic + molecular diversity. This diversity varied from 0 to 1.29 among the 117 accessions, with an average dissimilarity among genotypes of 0.51. Joint analysis of phenotypic and molecular diversity indicated that the genetic diversity of the physic nut germplasm was 156% and 64% higher than the diversity estimated from phenotypic and molecular data, respectively. These results show that Jatropha genetic variability in Brazil is not as limited as previously thought.

The biggest challenge for jatropha breeding is to identify superior genotypes that present high seed yield and seed oil content with reduced toxicity levels. Therefore, the objective of this study was to estimate genetic parameters for three important traits (weight of 100 seed, oil seed content, and phorbol ester concentration), and to select superior genotypes to be used as progenitors in jatropha breeding. Additionally, the genotypic values and the genetic parameters estimated under the Bayesian multi-trait approach were used to evaluate different selection indices scenarios of 179 half-sib families. Three different scenarios and economic weights were considered. It was possible to simultaneously reduce toxicity and increase seed oil content and weight of 100 seed by using index selection based on genotypic value estimated by the Bayesian multi-trait approach. Indeed, we identified two families that present these characteristics by evaluating genetic diversity using the Ward clustering method, which suggested nine homogenous clusters. Future researches must integrate the Bayesian multi-trait methods with realized relationship matrix, aiming to build accurate selection indices models.

[This corrects the article DOI: 10.1371/journal.pone.0157038.].

O objetivo deste trabalho foi estimar os parâmetros genéticos e determinar a eficiência da seleção simultânea de clones de eucalipto baseada em produtividade, estabilidade e adaptabilidade. Foram utilizados 21 clones, com 36 meses de idade, pertencentes ao programa de melhoramento genético da empresa Cenibra. O experimento foi instalado em delineamento de blocos ao acaso, em quatro ambientes, com 21 repetições de uma planta por parcela. Os clones foram avaliados quanto às variáveis: diâmetro à altura do peito, altura da planta e volume total com casca. Os parâmetros genéticos foram estimados pela metodologia de modelos mistos (REML/BLUP), e a seleção baseou-se no método da média harmônica do desempenho relativo dos valores genéticos (MHPRVG), em três estratégias: seleção com base no valor genético predito, tendo-se considerado o desempenho médio dos genótipos em todos os ambientes (sem efeito de interação) ou o desempenho em cada ambiente (com efeito da interação); e seleção simultânea quanto à produção, estabilidade e adaptabilidade. As particularidades dos ambientes influenciaram a expressão fenotípica dos clones. As estimativas de herdabilidade indicaram boas perspectivas para a seleção de clones com alta produtividade, estabilidade e adaptabilidade. A seleção simultânea otimiza a seleção de clones e pode ser usada na construção de populações de melhoramento e na recomendação de materiais genéticos para plantios comerciais.

The objective of this work was to estimate genetic gains in physic nut (Jatropha curcas) using selection indexes and to establish the best selection strategy for the species. Direct and indirect selection was carried out using different selection indexes, totalizing 14 strategies. One hundred and seventy five families from the active germplasm bank of Embrapa Agroenergy, Brasília, Brazil, were analyzed in a randomized complete block design with two replicates. The evaluated traits were: grain yield; seeds per fruit; endosperm/seed ratio; seed weight, length, width, and thickness; branches per plant at 0.5, 1.0, and 1.5 m; plant height; stem diameter; canopy projection on rows and between lines; canopy volume; juvenility (days to the first flowering); and height of the first inflorescence. Evaluations were done during the second year of cultivation. The use of selection indexes is relevant to maximize the genetic gains in physic nut, favoring a better distribution of desirable traits. The multiplicative and restrictive indexes are considered the most promising for selection.

This study presents the fi rst results of the sample analysis of two boreholes drilled in a quarry located in the Arcos region(MG). Petrographic analysis (macro- and microscopic observations) was performed and made possible to study in detailan approximately 175 meter-section, which shows the basement and 10 sedimentary units. The basement is represented bydark green to gray fi ne- to medium-grained granodiorite. At the base of the sedimentary sequence, Unit 1 is representedby a decimetric layer of polymictic diamictite and is overlain by the impure limestones of Unit 2. Unit 3 is carbonatic andcontains calcilutite and layers of carbonaceous shale. This unit gradually changes to Unit 4, which is composed of marland mudstone. Unit 5 is composed of a thick sequence of massive calcarenites, which begins to show lamellar layers andmicrobial structures in Unit 6. Unit 7 is similar to the previous one, but contains several intraclastic layers. The numberof lamellar layers decreases sharply, giving rise to a thick interval with considerable granulometric variations in Unit 8, which grades to the oolitic calcarenite of Unit 9. At the top of the sequence, Unit 10 is a thick package of stromatolitic dolarenite. Thisstratigraphic arrangement allows the identifi cation of progradational/retrogradational trends. The sedimentological features, especially those present in the basal portion, suggest that at least part of the carbonatic sequence could represent a cap carbonate, supporting a glacial origin for the diamictite. Other data also collected from the basal units suggest that changes occurred in the source area at the beginning of the fi lling of the basin.

Rinossinusite Nosocomial é uma complicação frequente de pacientes tratados em UTI. É importante o diagnóstico e tratamento precoce para prevenir complicações graves como pneumonia, sepse, meningite e abscesso intracraniano. OBJETIVO: Identificar os agentes causadores de sinusite em UTI através do swab nasal e da punção de seio maxilar, correlacionando seus resultados. MÉTODO: Pacientes atendidos nas unidades de terapia intensiva com diagnóstico tomográfico de sinusopatia maxilar uni ou bilateral foram submetidos ao swab nasal e punção do seio acometido com material enviado para cultura e antibiograma. RESULTADOS: O presente estudo avaliou 22 pacientes. Houve concordância entre o agente microbiano isolado no swab e na punção em 14 dos 22 casos (63%). A flora aeróbia gram negativa foi a mais encontrada com predomínio da Pseudomonas aeruginosa (29% nas punções), seguido de Proteus mirabillis (26%) e Acinetobacter baumanni (14%). Houve alto índice de resistência aos antibióticos usados. CONCLUSÃO: A punção direta do seio maxilar acometido em pacientes em UTI com sinusite parece ser o melhor método para identificar os agentes bacterianos e, através do seu antibiograma, direcionar a conduta terapêutica antimicrobiana. O swab mostrou ter pouco valor diagnóstico, com concordância de 63%, podendo ser reservado para casos onde a punção está contraindicada.Nosocomial sinusitis is a common complication of patients in ICUs. Its diagnosis is important, and early treatment is required to avoid serious complications such as pneumonia, sepsis, meningitis, and intracranial abscesses. AIM: To identify the germs causing sinusitis in ICUs by nasal swabs and maxillary sinus puncture, and to correlate these results. METHODS: ICU patients with a diagnosis (CT confirmed) of maxillary sinusitis underwent nasal swab and puncture of the sinus to collect material for culture and antibiogram. RESULTS: This study evaluated 22 patients. The microbial agent isolated in the swab correlated with the agent in the puncture in 14 of 22 cases (63%). Gram-negative bacteria were the most frequent, as follows: Pseudomonas aeruginosa (29% of punctures), following by Proteus mirabillis (26%) and Acinetobacter baumanni (14%). The resistance index in the antibiogram was high to antibiotics. CONCLUSION: Maxillary sinus puncture of ICU patients with sinusitis appears to be the best method for identifying bacteria; antibiograms demonstrate resistance to therapy. The swab has little diagnostic value; the correlation was 63%. It may be used when sinus puncture is contraindicated.

O objetivo deste trabalho foi evidenciar diferenças entre modelos de regressão, obtidos pelo método de Eberhart & Russell, na análise de adaptabilidade e estabilidade de comportamento de genótipos, e propor uma metodologia de agrupamento dos modelos similares. O teste para verificar a identidade de modelos foi empregado em dados de avaliação de 14 genótipos de milho em oito ambientes. Uma vez rejeitada a hipótese de igualdade dos modelos de regressão, realizou-se o agrupamento desses modelos com base no cálculo do quadrado médio da redução (QMRed) entre pares dos modelos de regressão. Após a obtenção desses valores, foi selecionado o de menor magnitude e verificada sua significância pelo teste F. NA hipótese de esse QMRed não ser significativo, o par de modelos relacionado a ele forma o grupo inicial. O método para verificar a identidade de modelos pode ser usado com sucesso no agrupamento de equações de regressão linear obtidas pelo método de Eberhart & Russell com o objetivo de estudar a adaptabilidade e a estabilidade de genótipos. O método de agrupamento de modelos similares permite formar grupos de genótipos com o mesmo comportamento estatístico

O objetivo deste trabalho foi verificar o efeito do tamanho da coleção original de germoplasma sobre eficácia de diferentes métodos de agrupamento e de amostragem, utilizados na obtenção de coleções nucleares, e comparar esses métodos no estabelecimento de coleções nucleares. Foram simulados sete tamanhos de coleções originais e utilizadas sete estratégias de amostragem para estabelecimento de coleções nucleares, com uso de caracteres morfo-agronômicos. Oito estratégias de obtenção de coleção nuclear foram empregadas, seis com técnicas de agrupamento (Tocher e Tocher sequencial) e duas sem agrupamento (aleatória e Tocher invertido). Nas estratégias de agrupamento, foram empregadas as amostragens constante, logarítmica e proporcional. Determinaram-se a variância explicada, o valor do coeficiente de determinação, o coeficiente de coincidência e o coeficiente de coincidência do desvio-padrão entre a coleção nuclear e a coleção original. As estratégias de amostragem constante e logarítmica geram coleções nucleares representativas da coleção original. O agrupamento de Tocher sequencial é mais eficaz na representação da coleção original pela coleção nuclear do que o agrupamento de Tocher. Entre as estratégias avaliadas, a amostragem pelo método de Tocher com critério de aglomeração inverso foi a mais eficiente na geração de coleções nucleares representativas das coleções originais

The objective of this work was to estimate the genetic parameters and variability among accessions (half-sib families) of physic nut (Jatropha curcas) during the early stages of development. For this study, 110 accessions in the first year of development of the physic nut germplasm bank, maintained at Embrapa Cerrados, DF, Brazil, were evaluated in situ. The experiment was established in a randomized complete block design, with two replicates and five plants per plot arranged in rows at 4x2 m spacing. Grain yield, total number of branches per plant, plant height, stem diameter, canopy projection on the row, canopy projection between rows, canopy volume, number of days until first flowering and height of the first inflorescence were evaluated. Estimates of vegetative genetic parameters showed the existence of genetic variability in the physic nut germplasm bank. Physic nut accessions of the germplasm bank were grouped into five similarity groups based on character divergence. Although preliminary, the obtained results are promising for showing potential for Jatropha improvement with selective efficiency.O objetivo deste trabalho foi estimar os parâmetros genéticos e a variabilidade entre acessos (famílias de meios-irmãos) de pinhão-manso (Jatropha curcas) no estágio inicial de desenvolvimento. Para este estudo, foram avaliados in situ 110 acessos, no primeiro ano de desenvolvimento, do banco de germoplasma mantido na Embrapa Cerrados. O experimento foi implantado em delineamento de blocos completos ao acaso, com duas repetições e cinco plantas por parcela, dispostas em linha no espaçamento de 4x2 m. Foram avaliados os caracteres: produção de grãos, número total de ramos por planta, altura de plantas, diâmetro de caule, projeção da copa na linha, projeção da copa na entrelinha, volume da copa, numero de dias para o primeiro florescimento e altura da primeira inflorescência. As estimativas dos parâmetros genéticos de caracteres vegetativos mostraram a existência de variabilidade genética no banco de germoplasma de pinhão-manso. Os acessos do banco de germoplasma de pinhão-manso foram agrupados em cinco grupos de similaridade, com base na divergência dos caracteres avaliados. Embora preliminares, os resultados obtidos são promissores por mostrar o potencial para o melhoramento de Jatropha com eficiência seletiva.

O objetivo deste trabalho foi avaliar uma metodologia de análise de adaptabilidade e estabilidade fenotípica de genótipos de café baseada em regressão não paramétrica. A técnica utilizada difere das demais, pois reduz a influência na estimação do parâmetro de adaptabilidade de algum ponto extremo, ocasionado pela presença de genótipos com respostas demasiadamente diferenciadas a determinado ambiente. Foram utilizados dados provenientes de um experimento sobre produtividade média de grãos de 40 genótipos de café (Coffea canephora), com delineamento em blocos ao acaso, com seis repetições. Os genótipos foram avaliados em cinco anos (1996, 1998, 1999, 2000 e 2001), em dois locais (Sooretama e Marilândia, ES) no total de dez ambientes. A metodologia proposta demonstrou ser adequada e eficiente, pois extingue os efeitos impróprios induzidos pela presença de pontos extremos e evita a recomendação incorreta de genótipos quanto à adaptabilidade.The objective of this work was to evaluate a methodology of phenotypic adaptability and stability analyses of coffee genotypes based on nonparametric regression. The technique used differs from other techniques because it reduces the influence of extreme points resulting from the presence of genotypes whose answers to a certain environment are too different on the estimation of the adaptability parameter. Data from an experiment studying the average yield of 40 coffee (Coffea canephora) genotypes in a randomized block design with six replicates were used to evaluate the method. The genotypes were evaluated along five years (1996, 1998, 1999, 2000 and 2001) in two locations (Sooretama and Marilândia, ES, Brazil), in a total of ten environments. The methodology proposed proved adequate and efficient, since it eliminates the disproportionate effects induced by the presence of extreme points and avoids misleading recommendations of genotypes in terms of adaptability.

As high-throughput genomic tools, such as the DNA microarray platform, have lead to the development of novel genotyping procedures, such as Diversity Arrays Technology (DArT) and Single Nucleotide Polymorphisms (SNPs), it is likely that, in the future, high density linkage maps will be constructed from both dominant and co-dominant markers. Recently, a strictly genetic approach was described for estimating recombination frequency (r) between co-dominant markers in full-sib families. The complete set of maximum likelihood estimators for r in full-sib families was almost obtained, but unfortunately, one particular configuration involving dominant markers, segregating in a 3:1 ratio and co-dominant markers, was not considered. Here we add nine further estimators to the previously published set, thereby making it possible to cover all combinations of molecular markers with two to four alleles (without epistasis) in a full-sib family. This includes segregation in one or both parents, dominance and all linkage phase configurations.

O objetivo deste trabalho foi avaliar parâmetros genéticos e comparar os ganhos preditos por meio de diferentes métodos de seleção em famílias de meios-irmãos de Eucalyptus urophylla. Foi utilizada seleção entre e dentro, seleção combinada e seleção com base em modelos mistos (REML/BLUP) para os caracteres diâmetro à altura do peito, altura total e volume total com casca. Foi utilizado o teste de progênie constituído de 100 famílias de meios-irmãos com 55 meses de idade, em espaçamento de 3x2 m, em delineamento de blocos ao acaso, com cinco repetições. As progênies apresentaram variabilidade genética significativa e elevada magnitude de herdabilidade para os caracteres estudados, o que evidencia alto controle genético e condições favoráveis para seleção. Todos os métodos avaliados foram eficientes para aplicação no melhoramento de eucalipto. No entanto, a seleção combinada e a seleção por modelos mistos (BLUP) proporcionam estimativas de ganhos significativamente maiores às obtidas com a seleção entre e dentro, e maior eficiência na escolha dos melhores indivíduos dentro da população.The objective of this work was to evaluate genetic parameters and to compare predicted gains using different selection methods in half-sib families of Eucalyptus urophylla. Within and between selection, combined selection and selection based on mixed model equations (REML/BLUP) were used for the traits diameter at breast height, total height and total volume with bark. The progeny test used consisted of 100 55-month-old half-sib families distributed in a 3x2-m spacing, in randomized complete block design with five replicates. The progenies showed significant genetic variability and high heritability for the studied traits, which indicates high genetic control and favorable conditions for selection. All the methods tested were efficient in eucalyptus breeding. However, the combined selection and the selection based on mixed models (BLUP) provided gains significantly larger than those obtained with within and between selections, and were more efficient in the selection of the best individuals in the population.

Avestruzes são ratitas originárias da África, sendo encontradas no Brasil, principalmente, em criatórios comerciais, os quais vêm se expandido no país devido ao potencial reprodutivo e alto valor comercial de seus produtos como carne, couro, gordura, plumas e ovos. Porém, as parasitoses são causas de grandes prejuízos econômicos e morte nesses criatórios. Em consequência disso, objetivou-se identificar os ectoparasitos que acometem avestruzes de criatórios comerciais no Rio Grande do Sul. Para tanto, foram coletadas, ao acaso, amostras de plumas e cabeças de 34 avestruzes, durante o abate, no frigorífico de Júlio de Castilhos, Rio Grande do Sul (RS). As amostras de plumas, as cabeças e as fossas nasais foram lavadas, individualmente, com água contendo detergente. Em seguida, o material foi tamisado em malha 150µm e examinado ao estereomicroscópio para coleta dos ectoparasitos. Nas plumas, foram encontrados piolhos e ácaros, os quais foram clarificados em salicilato de metila e lactofenol, respectivamente, e identificados como Struthiolipeurus rheae e Struthiopterolichus sculpturatus. Este é o primeiro registro de ocorrência desses ectoparasitos em avestruzes no Rio Grande do Sul.Ostriches are originated from Africa, and in Brazil they are mostly found in commercial farms which are developing in Brazil due to the great reproductive potential and the great economic value of its products that include meat, leather, feathers and eggs. However, parasitosis causes death of the birds and economic failure. Therefore, the aim of this research was to identify these ectoparasites that infect ostriches from commercial farms in the Rio Grande do Sul state, Brazil. Feathers and heads were collected randomly from 34 ostriches slaughtered in the city of Julio de Castilhos, RS. The feathers, heads and nasal cavity were individually cleaned in water with detergent. Following this, the material was sieved in a 150µm sieve and examined by stereomicroscope to search for ectoparasites search. Lice and mites were found in the feathers. The lices were clarified using metil salicilate and the mites by lactophenol. The lices were identified as Struthiolipeurus rheae and the mites as Struthiopterolichus sculpturatus. This is the first description of these arthropods in ostriches in Rio Grande do Sul.

A seleção precoce de clones que possuam níveis elevados de matéria seca e baixos teores de açúcares redutores é uma necessidade nos programas de melhoramento para a qualidade de processamento da batata (Solanum tuberosum L.) na forma de palitos fritos ou chips. A seleção precoce tornou-se possível com a utilização de marcadores genéticos, visto que permitem a identificação precisa de indivíduos superiores. Assim, procura-se cada vez mais encontrar marcadores capazes de caracterizar tais indivíduos e utilizá-los via seleção assistida. O objetivo deste trabalho foi avaliar a eficiência da seleção assistida, utilizando os marcadores identificados por ANDREU (2004) que estariam associados ao teor de matéria seca e açúcares redutores em tubérculos de batata. Clones provenientes de 20 famílias foram avaliados nas gerações de plântula (P), primeira geração clonal (C1) e segunda geração clonal (C2). As estimativas das correlações simples para os caracteres entre gerações foram significativas, porém, baixas, confirmando a inviabilidade de se efetuar a seleção precoce nas primeiras gerações com base apenas em informações fenotípicas. Os marcadores utilizados forneceram um total de 16 marcas. Pela regressão múltipla stepwise, apenas sete dessas marcas tiveram associação com os caracteres estudados. Além disso, nenhuma marca associada ao teor de matéria seca de tubérculos na geração C1 teve associação significativa na geração C2. Isso também foi observado com o teor de açúcares redutores, o que é um indicativo da interação QTLs x ambientes. A seleção assistida não se mostrou eficiente em relação à fenotípica em nenhum dos casos avaliados, portanto, não sendo útil em uma possível seleção precoce. Esses resultados indicam que tais marcadores não estão próximos aos genes controladores dos caracteres desejados, sendo necessária a identificação de novos marcadores mais associados que possibilitem maior eficiência da seleção assistida.Early generation selection for clones with high content of tuber dry matter and low levels of reducing sugars is required for potato (Solanum tuberosum L.) processing. Selection of superior clones at early generations became possible with the deployment of genetic markers, and can precisely identify the superior individuals. Therefore, it is necessary to identify genetic markers closely linked to genes of interest to do assisted selection. The aim of this research was to evaluate the efficiency of marker assisted selection with genetic markers previously identified by ANDREU (2004), which are assumed to be associated with dry matter and reducing sugars content in potato tubers. Clones from 20 families were evaluated during the seedling generation (S), first clonal generation (C1) and second clonal generation (C2). The estimated coefficients of correlation for all traits among generations were significant, even though of low magnitude, confirming that selection at early generation based only on phenotypic traits is inviable. A total of sixteen bands were amplified using these markers. However, by multiple stepwise regression, only seven of these bands showed association with the evaluated traits. Moreover, no markers associated with dry matter and reducing sugars content in the C1 were significantly associated with these traits in the C2, suggesting the existence of QTLs x environment interactions. The marker assisted selection resulted less efficient than the phenotypic selection in all cases studied, and thus is not recommended for early generation selection of clones for the processing industry. These results suggest that the markers used are not closely linked to the genes controlling the traits most important for processing. Therefore, it is important to identify new markers closely linked with such traits of interest that could improve the efficiency of marker assisted selection.

The use of genetic maps is a useful tool in genetic research. The association between map distance andrecombination frequency is expressed by a genetic mapping function. However, several of these functions do not presupposethe joint recombination percentage. In other words, they are not multilocus probabilities. This work aimed to compare,through simulations, the efficiency in the use of different mapping functions with and without multilocus analysis as a tool inthe construction of genetic maps. A genome constituted of three linkage groups (50, 100 and 200 cM) was simulated for acomparative study. Four mapping populations were simulated, F2, with 50, 100, 200 and 400 individuals, with 10 replicaseach. It was verified, after the analyses, that the multilocus analysis was not efficient to rescue the size of the connectiongroups, concluding that the non use of the multilocus analysis would be viable.

O objetivo deste trabalho foi obter as estimativas de freqüência de recombinação, por meio de simulação, para diferentes situações do mapeamento genético de famílias de irmãos completos. Foi simulado um genoma constituído de três grupos de ligação, em que cada um apresentava 11 marcas moleculares multialélicas, codominantes, distribuídas a cada 10 cM. A partir desse genoma, foram simulados dois cenários: um com genitores completamente informativos e outro com genitores formados aleatoriamente. Após a obtenção de todas as estimativas das freqüências de recombinação, concluiu-se que, para locos completamente informativos, pode-se calcular a freqüência de recombinação entre pares de locos, a partir da freqüência gamética de cada genitor ou a partir da freqüência genotípica da progênie. Para locos parcialmente informativos, a obtenção da freqüência de recombinação a partir da freqüência genotípica conjunta é mais apropriada.The objective of this work was to obtain the estimates of recombination frequency, through simulation, for different situations in genetic mapping involving full sibling families. A genome with three linkage groups simulated, each one with 11 molecular marks which were multi-allelic, codominants, with saturation of 10 cM. Starting from this genome, two situations were simulated: one with informative genitors, and other with genitors formed randomly. Once all the recombination frequencies were estimated, it was found out that in completely informative loci, the recombination frequency can be calculated among equal pairs of loci starting from the gametic frequency of each genitor, or starting from the genotipic frequency of the progeny. For partially informative loci, the recombination frequency starting from the united genotipic frequency is more appropriate.

O objetivo deste trabalho foi avaliar o tamanho ótimo de populações de irmãos completos, para estudos de mapas de marcadores moleculares, por meio de simulações de genomas e tamanhos de populações. Foram simulados genomas parentais e amostras de populações de família de irmãos completos do tipo completamente informativas, e também não completamente informativas. As amostras geradas foram de 100, 200, 400 e 600 indivíduos, com três grupos de ligação cada, e 11 marcas moleculares codominantes e multialélicas, espaçadas a dez centimorgans por grupo de ligação. Foram realizadas 100 repetições por amostra. Para populações completamente informativas, o tamanho populacional de 200 indivíduos é suficiente para recuperar as informações originais, contudo, para a população não completamente informativa, é necessária a utilização de uma população maior, de 600 indivíduos.The objective of this work was to evaluate the optimum size of populations for the study of genetic mapping of full sibling families, through data simulation of genome and populations. Parental genomes and population samples of full sibling families of both completely and non-completely informative types, were simulated. The generated samples had 100, 200, 400 and 600 individuals, with three linkage groups each, and 11 codominant multi-allelic molecular marks, spaced by ten centimorgans in each linkage group. One-hundred repetitions were accomplished by sample. In completely informative populations, the optimum size of 200 individuals is enough to rescue the original information, however, for the non-completely informative population, it is necessary a larger population, with 600 individuals.