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The mangaba is a fruit tree with great potential for the northeast of Brazil. Due to the scarcity of improved cultivars, and as it is a species that is still in the process of domestication, exploitation has been based on rational and sustainable extractivism by farmer-gatherers. The aim of this study was to analyse the correlations between technological variables of the mangaba, and to carry out an early selection of the genotypes that make up the base population of the mangaba improvement program of Embrapa Meio-Norte. The variables fruit weight, pulp weight and percentage pulp show significant correlation with fruit length and fruit diameter, allowing indirect selection for the first set of variables by means of the latter, which are easily measured. Genotypes 4, 13, 16, 21, 25, 32, 35 and 49 show a positive association with fruit weight, fruit length, fruit diameter, pulp weight and percentage weight, and are therefore candidates for selection. Principal component 1 is associated with fruit weight, fruit length, fruit diameter, skin weight, number of seeds per fruit, seed weight, TTA and pulp weight. These variables can be selected with greater mathematical certainty, since this component concentrates more information regarding variability and is therefore more important. Made available in DSpace on 2020-04-28T04:39:38Z (GMT). No. of bitstreams: 1 ART20001.pdf: 472671 bytes, checksum: 9d02d2be9575adb8197b3fe8623a36de (MD5) Previous issue date: 2020

Psoriasis and psoriatic arthritis are chronic, relapsing, immune-based diseases. Psoriatic patients may have nail involvement in 50 to 80% of cases, and this may reach 85% in patients with joint disease, in spite of the fact that the relationship between psoriasis and onychomycosis is not well established. The aim of this study was to investigate the occurrence of onychomycosis in patients with nail disorders and diagnosis of psoriasis and psoriatic arthritis. This was a cross-sectional study in which 38 patients diagnosed with psoriasis and/or psoriatic arthritis were interviewed and had altered nail samples analysed by mycological and histopathological exams. Twenty-two (57.89%) patients had a confirmed diagnosis for onychomycosis. Seventeen (44.8%) had a positive direct mycological examination, 16 (42.1%) had positive cultures, and 12 (31.6%) were positive for fungi by histopathological examination. Dermatophytes were identified in nine (56.3%) cultures, and of these, eight were Trichophyton rubrum and one T. tonsurans. Yeasts were isolated in seven patients (43.75%), which included four Candida parapsilosis and three C. albicans. Six patients (15.78%) were not using immunosuppressive therapy, and the others were using methotrexate, etanercept, adalimumab, infliximab, secukinumab, or golimumab, in monotherapy or in combination with other drugs. The confirmed onychomycosis rate in patients using methotrexate alone was 92.8% (n = 13). We concluded that it is possible that there is a positive relationship between psoriatic disease and onychomycosis. And we highlight that it is also worth investigating in the future the possible role of immunosuppressive therapy (mainly methotrexate) as a predisposing factor for the development of fungal infections in psoriatic patients.

Some species of Klebsiella, such as Klebsiella pneumoniae and Klebsiella oxytoca, are important nosocomial pathogens frequently involved in outbreaks in Neonatal Intensive Care Units (NICU) and have the ability to form a biofilm. This study aims to evaluate the biofilm production of K. pneumoniae and K. oxytoca isolates collected from the hands of health professionals, neonates' blood and the environment of a Brazilian NICU, using three colorimetric methods and a classical method of counting the colony-forming units and compare the analysis among these techniques. The biofilm formation was carried out by the microplate technique, using three colorimetric assays: crystal violet, safranin and 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl) -5 [(phenylamino) arbonyl] - 2H-tetrazolium hydroxide (XTT). Also, colony-forming units were determined. Twenty-eight isolates of K. pneumoniae were collected from the blood, hands and environment and five of K. oxytoca from the hands and environment. All of them were strong biofilm producers, but K. pneumoniae isolates produced more biofilm than K. oxytoca when compared to the American Type Culture Collection (ATCC) strains used as positive controls. The number of viable cells in the biofilm produced by K. pneumoniae isolated from blood was significantly higher than in the control sample. Regarding the three colorimetric tests used in the study, the violet crystal obtained a higher absorbance average. The use of crystal-violet and XTT in the evaluation of biofilm in vitro make possible a complete analysis, since that it can quantify the total biomass (including the extracellular matrix) and evaluate the metabolic activity. In conclusion, this study identified isolates of K. pneumoniae and K. oxytoca that produce biofilms in the NICU and the bloodstream of neonates. This fact deserves attention since these patients are immunocompromised. The best methods will be chosen to answer research questions by always adopting more than one method so that more than one parameter or component of the biofilm is analyzed.

Mango ( Mangifera indica L.) trees stand out among the main fruit trees cultivated in Brazil. The mango rosa fruit is a very popular local variety (landrace), especially because of their superior technological characteristics such as high contents of Vitamin C and soluble solids (SS), as well as attractive taste and color. The objective of this study was to select a breeding population of mango rosa (polyclonal variety; ≥5 individuals) that can simultaneously meet the fresh and processed fruit markets, using the multivariate method of principal components and the biplot graphic. The principal components, biplot graphic, and phenotype correlations were obtained using the R (2012) software. Pulp percentage and the pulp, skin, and seed mass variables can be indirectly selected using the smallest fruit diameter, which allowed an easier measurement. The P23R AREA3, P30R AREA3, and P32R AREA3 genotypes are selection candidates due to the presence of alleles, which are important agro-technological traits for mango breeding. This study showed that the biplot analysis is a valuable tool for decision making and visualization of interrelationships between variables and genotypes, facilitating the mango selection process. RESUMO: Dentre as principais fruteiras cultivadas no Brasil, destaca-se a mangueira ( Mangifera indica L.). A manga rosa é uma variedade local bastante apreciada, especialmente devido a suas características tecnológicas superiores, tais como alto teor de Vitamina C, conteúdo de sólidos solúveis totais (SS), bem como sabor e cor atraentes. O objetivo deste estudo foi selecionar uma população de melhoramento de manga rosa (variedade policlonal; ≥5 indivíduos) que atenda simultaneamente aos mercados de frutas frescas e processadas, empregando o método multivariado de componentes principais e o gráfico biplot. Os componentes principais, o gráfico biplot e as correlações fenotípicas foram obtidos usando o software R (2012). As variáveis porcentagem de polpa e as massas de polpa, casca e semente podem ser selecionadas indiretamente por meio do diâmetro menor do fruto, que permite uma mensuração mais fácil. Os genótipos P23R ÁREA3, P30R ÁREA3, e P32R ÁREA3 são candidatos à seleção devido à presença de alelos para caracteres agrotecnológicos, que são importantes para o melhoramento da manga. Este estudo mostrou que a análise biplot é uma ferramenta valiosa para a tomada de decisão e visualização das inter-relações entre variáveis e genótipos, facilitando o processo seletivo da manga.

The cajuí Anacardium spp., which is similar to the caju Anacardium Ocidentale L., is a species adapted to edaphic-climatic conditions of the biome Cerratinga (Cerrado e Caatinga). Its fruit is composed of one swollen stalk (pedicel) which is formed by nutritional reserves rich in vitamin C and drupe (cashew nut). It is also rich in protein and lipids, but with smaller size. This paper focuses on investigating the applicability of the biplot graphical analysis in the process of selective breeding of cajuí population. The cajuí working population in Embrapa Meio Norte comprises of 11 genotypes collected in areas of natural habitat in the state of Piaui. The experiment was designed in randomized complete blocks with two plants per plot and four replications. A graphical analysis (biplot) was used to study the relationships between variables and behavior of the experimental genotypes. This was implemented to principal component analysis based on singular value decomposition biplot. The total variable weight can be predicted from length of peduncle, basal and apical diameter of peduncle, and variables of easy mensuration. Genotypes M40A, M23, M14, and M17 are similar to each other and they have high amounts of brown, apical and basal diameter of the peduncle, total weight, and peduncle length. They are considered as candidates selected for consumption in natura and industrial processing. The graphical analysis (biplot) showed robustness in the presentation of relationships between variables considered and the indication of the selection candidate genotypes in the population studied. Made available in DSpace on 2019-12-09T18:16:59Z (GMT). No. of bitstreams: 1 ART19049.pdf: 486166 bytes, checksum: 2f2a75b10f93ffaf655e6decb28e7e58 (MD5) Previous issue date: 2019

Infections by Candida species are a high-impact problem in public health due to their wide incidence in hospitalized patients. The goal of this study was to evaluate frequency, susceptibility to antifungals, and genetic polymorphism of Candida species isolated from clinical specimens of hospitalized patients. The Candida isolates included in this study were obtained from blood cultures, abdominal fluids, and central venous catheters (CVC) of hospitalized patients at the Clinical Hospital of the Federal University of Uberlândia during the period of July 2010 - June 2011. Susceptibility tests were conducted by the broth microdilution method. The RAPD-PCR tests used employed initiator oligonucleotides OPA09, OPB11, and OPE06. Of the 63 Candida isolates, 18 (28.5%) were C. albicans, 20 (31.7%) were C. parapsilosis complex species, 14 (22.2%) C. tropicalis, four (6.4%) C. glabrata, four (6.4%) C. krusei, two (3.3%) C. kefyr, and one (1.6%) C. lusitaniae. In vitro resistance to amphotericin B was observed in 12.7% of isolates. In vitro resistance to azoles was not detected, except for C. krusei. The two primers, OPA09 and OPB11, were able to distinguish different species. Isolates of C. albicans and C. parapsilosis complex species presented six and five clusters, respectively, with the OPA09 marker by RAPD-PCR, showing the genetic variability of the isolates of those species. It was concluded that members of the C. parapsilosis complex were the most frequent species found, and most isolates were susceptible to the antifungals amphotericin B, flucozanole, and itraconazole. High genetic polymorphisms were observed for isolates of C. albicans and C. parapsilosis complex species, mainly with the OPA09 marker. As infecções causadas por espécies de Candida são problema de grande impacto para a saúde pública, devido à alta incidência em pacientes hospitalizados e como causa de mortalidade. O presente estudo teve como objetivo avaliar a frequência de Candida spp. isoladas de pacientes hospitalizados, assim como a sensibilidade aos antifúngicos e o polimorfismo genético por RAPD-PCR. Os microrganismos incluíram isolados de hemocultura, líquido abdominal e ponta de cateter venoso central de pacientes internados no Hospital de Clínicas da Universidade Federal de Uberlândia, região do Triângulo Mineiro, Minas Gerais, Brasil, no período de julho de 2010-junho de 2011. Os testes de sensibilidade aos antifúngicos foram realizados por microdiluição em caldo e na análise por RAPD-PCR foram utilizados os oligonucleotídeos OPA09, OPB11, e OPE06. Dos 63 isolados, 18 (28,5%) foram C. albicans, 20 (31,7%) C. parapsilosis, 14 (22,2%) C. tropicalis, quatro (6,4%) C. glabrata, quatro (6,4%) C. krusei, dois (3,3%) C. kefyr, e um (1,6%) C. lusitaniae. Resistência in-vitro à anfotericina B foi observada em 12,7% dos isolados. Não foi observada resistência in-vitro aos azólicos, exceto para os isolados de C. krusei. Os oligonucleotídeos OPA09 e OPB11 possibilitaram distinguir diferentes espécies. Isolados de C. albicans apresentaram seis clusters e o complexo C. parapsilosis, cinco clusters, com o iniciador OPA09, por RAPD-PCR, mostrando a variabilidade genética daquelas espécies. Conclui-se que o complexo C. parapsilosis foi a espécie mais frequente, e a maioria dos isolados foi sensível in vitro aos antifúngicos testados. Alto polimorfismo genético foi observado para os isolados de C. albicans e complexo C. parapsilosis, principalmente com o oligonucleotídeo OPA09.

The mangabeira its figure out among the mains native fruit tree explored by extractivism in Brasil. The objective evaluate the genetic divergence of landraces in orientation of crosses using multivariate techinics. The complete random blocks experimental design with four repetitions was used to evaluate twelve quantitative characteristics from twelve genotypes elite of mangabeiras concerning to divergence genetic using the software R (2012). Three groups genetically divergent were composed by biplot graphic and stored by UPGMA cluster analysis (Unweighted Pair-Group Method using Arithmetic Average / Weighted Clustering Method not using the Arithmetic Mean) showing genetic diversity and variability among 12 mangabeira accesses. Forty-four possible crosses are planned among genotypes of genetically dissimilar three groups and six among individuals in group III. Multivariate techniques were appropriate in the study of genetic divergence. Made available in DSpace on 2018-08-02T00:56:00Z (GMT). No. of bitstreams: 1 26665.pdf: 882569 bytes, checksum: cc24885f08b6d43970c2cbba4e526af8 (MD5) Previous issue date: 2018-08-01

Cryptococcosis, a systemic disease caused by the fungus Cryptococcus neoformans/ Cryptococcus gattii is more severe in immunocompromised individuals. This study aimed to analyze the epidemiology of the disease, the molecular characteristics and the antifungal susceptibility of C. neoformans isolated from patients treated in a Brazilian university hospital. This retrospective study was conducted in the Clinical Hospital, Federal University of Uberlândia, and evaluated cases of cryptococcosis and strains of C. neoformans isolated from 2004 to 2013. We evaluated 41 patients, 85% of whom were diagnosed with AIDS. The fungus was isolated from the cerebrospinal fluid (CSF) of 21 patients (51%); 19.5% had fungemia and in 24% the agent was isolated from the CSF and blood, concurrently. Meningoencephalitis was the most frequent (75%) manifestation of infection. Despite adequate treatment, the mortality of the disease was 58.5%. Most isolates (97.5%) presented the VNI genotype (serotype A, var. grubii) and one isolate was genotyped as C. gattii (VGI); all the isolates were determined as mating type MATa and showed susceptibility to the tested antifungals (fluconazole, voriconazole, amphotericin B and 5-flucytosine). Although AIDS detection rates remain stable, opportunistic infections such as cryptococcosis remain as major causes of morbidity and mortality in these patients.

The genotype by environment interaction (GEI)) has an influence on the selection and recommendation of cultivars. The aim of this work is to study the effect of GEI and evaluate the adaptability and stability of productivity (kg/ha) of nine maize genotypes using AMMI model (Additive Main effects and Multiplicative Interaction). The AMMI model is one of the most widely used statistical tools in the analysis of multiple-environment trials. It has two purposes, namely understanding complex GEI and increasing accuracy. Nevertheless, the AMMI model is a widely used tool for the analysis of multiple-environment trials, where the data are represented by a two-way table of GEI means. In the complete tables, least squares estimation for the AMMI model is equivalent to fitting an additive two-way ANOVA model for the main effects and applying a singular value decomposition to the interaction residuals. It assumes equal weights for all GEI means implicitly. The experiments were conducted in twenty environments, and the experimental design was a randomized complete block design with four repetitions. The AMMI model identified the best combinations of genotypes and environments with respect to the response variable. This paper concerns a basic and a common application of AMMI: yield-trial analysis without consideration of special structure or additional data for either genotypes or environments.

The colonization of the oral cavity is a prerequisite to the development of oropharyngeal candidiasis. Aims: The aims of this study were: to evaluate colonization and quantify Candida spp. in the oral cavity; to determine the predisposing factors for colonization; and to correlate the levels of CD4+ cells and viral load with the yeast count of colony forming units per milliliter (CFU/mL) in HIV-positive individuals treated at a University Hospital. Saliva samples were collected from 147 HIV patients and were plated on Sabouraud Dextrose Agar (SDA) and chromogenic agar, and incubated at 30 ºC for 72 h. Colonies with similar morphology in both media were counted and the result expressed in CFU/mL. Results: Of the 147 HIV patients, 89 had positive cultures for Candida spp., with a total of 111 isolates, of which C. albicans was the most frequent species (67.6%), and the mean of colonies counted was 8.8 × 10³ CFU/mL. The main predisposing factors for oral colonization by Candida spp. were the use of antibiotics and oral prostheses. The use of reverse transcriptase inhibitors appears to have a greater protective effect for colonization. A low CD4+ T lymphocyte count is associated with a higher density of yeast in the saliva of HIV patients. RESUMO A colonização da cavidade oral pode ser considerada um pré-requisito para o desenvolvimento de candidíase orofaríngea. Os objetivos deste estudo foram: avaliar e quantificar espécies de Candidaisoladas da cavidade oral, para determinar os fatores predisponentes para a colonização, e correlacionar os níveis de células CD4+ e carga viral em indivíduos HIV-positivos atendidos em um hospital universitário. Foram coletadas amostras de saliva de 147 pacientes portadores do HIV, as quais foram semeadas em Ágar Sabouraud Dextrose (ASD) e ágar cromogênico e incubadas a 30 °C por 72 horas. As colônias com morfologia semelhante em ambos os meios foram contadas e o resultado expresso em unidade formadora de colônias por mililitro (UFC/mL). Dos 147 pacientes HIV positivos, 89 apresentaram culturas positivas para Candidaspp., totalizando 111 isolados, e C. albicansfoi a espécie mais frequente (67,6%). A contagem média de colônias foi de 8.8 × 10³ UFC/mL. Os principais fatores predisponentes para colonização oral por Candidaspp. foram a utilização de antibióticos e de próteses orais. O uso de antirretroviral da classe de inibidores da transcriptase reversa pareceu ter maior efeito protetor para a colonização. Baixa contagem de linfócitos T CD4+ está relacionada com maior densidade de leveduras na saliva de indivíduos HIV positivos.

This work applies the three mode principal components analysis to analyze simultaneously the multiple attributes; to fit of models with additive main effects and multiplicative interaction effects (AMMI models) and the regressions models on sites (SREG models); to evaluate, respectively, the multivariate response of the genotype × environment interaction and the mean response of 36 genotypes of corn tested in 4 locations in Brazil. The results were presented by joint plots to identify the best genotypes for their adaptability and performance in the set of attributes.

Este trabalho teve os seguintes objetivos: propor uma sistemática para o estudo e a interpretação da estabilidade e adaptabilidade fenotípica, por meio do modelo de Tucker3; avaliar o uso do gráfico joint plot; e comparar os resultados obtidos pela metodologia de três entradas com os resultados obtidos pelos modelos AMMI e pela análise biplot. Os dados utilizados são relativos a experimentos com 13 genótipos de feijão conduzidos em nove experimentos. Os resultados indicaram que o gráfico joint plot facilita o entendimento da interação tripla e traz ao pesquisador informações mais reais sobre a interação tripla do que a modelagem AMMI de duas entradas; o genótipo 6 foi o que menos contribuiu para a interação, e os genótipos 12, 9 e 5 foram os que mais contribuiram para a interação. The present research had the following objectives: to propose a systematics for the study and the interpretation of the phenotypic stability and adaptability, through Tucker3 models; assess the use of the joint plot; comparing the results obtained by tucker3 model with the results obtained by biplot analysis and AMMI models. The data used are related to the experiments with 13 genotypes of beans that had been lead in 9 distinct experiments. The results indicated that the joint plot graph facilitates the understanding of triple interaction and bring to the researcher more real information about triple interaction, than AMMI modeling of two entries. The genotype 6 was the one which least contributed for the triple interaction and genotypes 12, 9 and 5 were those e which had contributed more for the interaction.

Made available in DSpace on 2021-07-14T10:37:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07. Added 1 bitstream(s) on 2021-07-14T11:34:43Z : No. of bitstreams: 1 S0103-84782009000400010.pdf: 367698 bytes, checksum: 3e022f2061df1ef77fb75780fa00e4b5 (MD5) Neste trabalho é apresentada a aplicação dos modelos AMMI com o propósito de analisar a interação entre genótipo e ambiente em experimentos agronômicos multiambientais com dados balanceados. São apresentados dois métodos de validação cruzada e o aperfeiçoamento desses métodos por meio da correção de autovalores, sendo estes ordenados por meio da regressão isotônica. É realizado um estudo comparativo entre esses métodos por meio de dados reais. Os resultados mostram para esse conjunto de dados que o método de EASTMENT & KRZANOWSKI (1982) seleciona um modelo mais parcimonioso. Além disso, quando esse método é aperfeiçoado com a correção dos autovalores, o número de componentes não se altera. O método de GABRIEL (2002) seleciona um maior número de termos no modelo, e, quando se aplica a correção de autovalores, o número de termos diminui. O aperfeiçoamento desses métodos por meio da correção de autovalores traz um grande benefício para o pesquisador do ponto de vista prático, uma vez que a seleção do número de termos multiplicativos representa um ganho do número de blocos (ou repetições), quando se utiliza o modelo AMMI em vez do modelo completo, sendo, portanto, melhor utilizar o modelo AMMI com correção dos autovalores e selecionar o número de componentes por meio do método de Eastment e Krzanowski. This paper presents an application of AMMI models - Additive Main effects and Multiplicative Interaction model - for a thorough study about the effect of the interaction between genotype and environment in multi-environments experiments with balanced data. Two methods of crossed validation are presented and the improvement of these methods through the correction of eigenvalues, being these rearranged by the isotonic regression. A comparative study between these methods is made, with real data. The results show that the EASTMENT & KRZANOWSKI (1982) method selects a more parsimonious model and when this method is improved with the correction of the eigenvalues, the number of components are not modified. GABRIEL (2002) method selects a huge number of terms to hold back in the model, and when this method is improved by the correction of eigenvalue, the number of terms diminishes. Therefore, the improvement of these methods through the correction of eigenvalues brings a great benefit from the practical point of view for the analyst of data proceeding from multi-ambient, since the selection of numbers of multiplicative terms represents a profit of the number of blocks (or repetitions), when the model AMMI is used, instead of the complete model. Universidade Estadual Paulista, Departamento de Bioestatística Universidade de São Paulo, Escola Superior de Agricultura Luiz de Queiroz Universidade Estadual Paulista, Departamento de Bioestatística

This study aimed to propose a clustering methodology with bootstrap resampling using the Additive Main Effects and Multiplicative Interaction Analysis (AMMI) to contribute to better prediction of phenotypic stability of genotypes and environments. It also aims to analyze the genetic divergence in the assessment of soybean lines, identify genotypes with high-yielding characteristics, with control of chewing and sucking insect pests, and cluster similar genotypes for the traits evaluated. A total of 24 experiments were conducted in randomized blocks, with two replications subdivided in experimental groups with common controls. AMMI with principal component analysis indicated that PC1 and PC2 were significant, explaining 83.9% of the sum of squares of the interaction. The first singular axis of AMMI analysis captured the highest percentage of "pattern" and, with subsequent accumulation of the dimensions of the axes, there was a decrease in the percentage of "pattern" and an increase in "noise". The Euclidean distance between genotype scores was used as the dissimilarity measure and clusters were obtained by the hierarchical method of Ward. Genotypes 97-8011, 97-8029, 97-8050 and IAS-5 had the best performance and are promising for recommendation purposes, with the greatest stability and best performance on grain yield. RESUMO O presente trabalho teve como objetivo propor uma metodologia de agrupamento com reamostragem bootstrap por meio do modelo AMMI (Additive Main Effects and Multiplicative Interaction Analysis), contribuindo para melhor predição da estabilidade fenotípica de genótipos e de ambientes. Ao mesmo tempo, analisar a divergência genética na avaliação de linhagens experimentais de soja, identificando genótipos que reúnam características de alta produtividade, com controle de insetos mastigadores e sugadores, reunindo grupos de genótipos similares para os caracteres avaliados. Foram conduzidos 24 experimentos aleatorizados em blocos com duas repetições subdivididas em conjuntos experimentais com testemunhas comuns. A análise AMMI por componentes principais indicou os dois primeiros eixos como significativos, os quais explicaram 83,9% da porção da soma de quadrados da interação. O primeiro eixo singular da análise AMMI capturou a maior porcentagem de "padrão" e, com acumulação subsequente das dimensões dos eixos, houve uma diminuição na porcentagem de "padrão" e um incremento de "ruídos". Utilizou-se a distância euclidiana entre escores de genótipos como medida de dissimilaridade e posteriormente obtidos os agrupamentos por meio do método hierárquico de Ward. Os genótipos 97-8011, 97-8029, 97-8050 e a testemunha IAS-5 se comportaram como os mais promissores para fins de recomendação, pois os resultados indicaram maior estabilidade e melhor performance quanto à produtividade de grãos.

In multi-environmental trials it is common for the genetic characteristics of the cultivars to be influenced by the environments. Thus, the study of tools that allow the analysis of the interaction between genotypes and environments and between QTLs (quantitative trait loci) and environments has gained more and more space among researchers in this area. However, collected data are not always suitable for use with already known models, making it necessary to search for more specific models for certain situations. In this research, we analyzed situations such as data showing hetero- geneity of error variance across environments and also contaminated data, which represent data with outlying observations. In such cases, models already known in the literature, such as the AMMI (additive main-effect and multiplicative interaction) model and the GGE (genotype main-effects + genotype environment interaction) model, are not indicated. Here, we verify the use of the robust AMMI model and weighted AMMI in the detection of QTLs and in the analysis of interactions. We also propose the weighted GGE model and evaluate its effectiveness, comparing it with other models. Two data sets were used. The first data from a simulated pepper (Capsicum annuum L.) back cross population using a crop growth model report genotype to phenotype in a nonlinear way, and the second the doubled-haploid Steptoe × Morex barley (Hordeum vulgare L.) population. Em ensaios multi-ambientais é comum que as características genéticas dos cultivares sejam influenciadas pelos ambientes. Desta forma, o estudo de ferramentas que permitam analisar a interação entre genótipos e ambientes e entre QTLs (locus de característica quatitativa) e ambientes tem ganhado cada vez mais espaço entre os pesquisadores desta área. Porém, nem sempre dados coletados são adequados para serem utilizados com modelos já conhecidos, sendo necessário a busca por modelos mais específicos a certas situações. Nessa pesquisa, analisamos situações como dados que apresentam heterogeneidade de variância dos erros ao longo dos ambientes e também dados contaminados, que representam dados com presença de outliers. Nesses casos, modelos já conhecidos na literatura, como o modelo AMMI (modelo de efeito principal aditivo e interação multiplicativa) e o modelo GGE (modelo de efeito principal de genótipo mais interação genótipo × ambiente), não são indicados. Aqui, verificamos o uso do modelo AMMI robusto e AMMI ponderado na detecção de QTLs e na análise de interações. Também, propomos o modelo GGE ponderado e avaliamos sua eficácia, comparando com outros modelos. Foram usados dois conjunto de dados. O primeiro conjunto de dados são dados simulados de pimentão (textit Capsicum annuum L.) de população cruzada usando modelo de crescimento de culturas para relacionar genótipos a fenótipos de maneira não linear e o segundo, dados de cevada de população duplo haplóide Steptoe × Morex (Hordeum vulgare L.).