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Item Incidence and severity of coffee leaf rust, cercosporiosis and coffee leaf miner in coffee progenies(Editora UFLA, 2018-07) Lima, Amador Eduardo de; Sampaio Junior, Hudinilson Gilberto; Castro, Elisa de Melo; Carvalho, Samuel Pereira de; Silva, Fabiano França da; Lima Junior, Sebastião de; Carvalho, Alex Mendonça deCoffee leaf rust is the main disease of this crop, however cercosporiosis and coffee leaf miner can also cause significant damage when they reach high levels of infestation. Plant genetic improvement for resistance is one of the best tools for controlling plant diseases. The objective in this work was to identify F 3 progenies of Coffea arabica with resistance to coffee leaf rust, which present a lower incidence and severity of cercosporiosis and coffee leaf miner. The treatments were constituted by 10 progenies, besides two cultivars coffee leaf rust susceptible, used as a control. The experimental design was a randomized block design (RBD), with two replicates, each block consisting of 12 plots randomly distributed, each corresponding to one treatments. The following characteristics were evaluated: coffee leaf rust intensity and severity, cercosporiosis and coffee leaf miner, plants vegetative vigor, grain maturity uniformity and plants height. The progeny averages were grouped by the Scott & Knott test at 5% probability. Progenies 27, 30 and 15 were selected, since they presented low incidence in relation to coffee leaf rust, cercosporiosis and coffee leaf miner, and will be used to continue the breeding program.Item Selection of Coffea arabica L. hybrids using mixed models with different structures of variance-covariance matrices(Editora UFLA, 2018-07) Pereira, Fernanda Aparecida Castro; Carvalho, Samuel Pereira de; Rezende, Tiago Teruel; Oliveira, Leonardo Luiz; Maia, Diego Rosa BaquiãoThis study aimed to evaluate different structures of variance-covariance matrices in modeling of productive performance of coffee genotypes over the years, and select hybrids of Coffea arabica using mixed models. A mixed linear model was used to estimate variance components, heritability coefficients, and prediction of genetic values of hybrids and cultivars. Three commercial cultivars and eight hybrids of C. arabica L. were evaluated. The field production after acclimatization of seedlings was conducted in March 2006. The yield averages from 2009, 2010, 2011, 2013, and 2014 agricultural years were evaluated. The selection criteria of models were used to test 10 structures of variance-covariance matrices, and later a model was chosen to estimate the components of variance, heritability coefficients, and prediction of genetic values. According to Bayesian information criterion (BIC), the best structure was ARMA (Autoregressive Moving Average); however, considering the Akaike Information Criterion (AIC) and corrected Akaike Information Criterion (AICC), the CSH (Heterogeneous Composite Symmetric) was indicated. The Spearman correlation between the genotypic values obtained in the models with ARMA and CSH type R matrix was 0.84. The high and positive correlation indicates that the best model could involve the R matrix with ARMA or CSH structure. The heritability of individual genotypes differed from heritability in broad sense, which considers the independence among agricultural years. Hybrids with higher performance were identified by ordering the genotypic effects, among them, H 2.2, H 4.2, and H 6.1 hybrids were highlighted.Item Comportamento agronômico de progênies e cultivares de cafeeiro com resistência específica à ferrugem(Editora UFLA, 2013-04) Costa, Joyce Cristina; Carvalho, Carlos Henrique de Siqueira; Matiello, José Braz; Almeida, Saulo Roque de; Carvalho, Samuel Pereira de; Baliza, Danielle PereiraObjetivando-se avaliar a produtividade e outras características agronômicas de progênies e cultivares de cafeeiro com resistência específica à ferrugem, foi conduzido um experimento na Fazenda Experimental do MAPA/Fundação Procafé, em Varginha, MG. Este foi instalado em janeiro de 2003, em blocos inteiramente casualizados, com 12 progênies e duas cultivares, cinco repetições e quatro plantas por parcela. Foram avaliadas as características de produtividade média dos grãos, estádio de maturação dos grãos e classificação por peneira. Os dados obtidos foram submetidos à análise de variância e quando houve efeito significativo dos tratamentos, as médias foram comparadas por meio do teste de Scott-Knott. Com o intuito de possibilitar a seleção indireta buscou-se conhecer o grau de associação das características em estudo, por meio das estimativas de correlação fenotípica entre as características avaliadas. E, posteriormente, para verificar a variabilidade existente entre as progênies foram estimadas as distâncias genéticas pelo método das Distâncias Generalizadas de Mahalanobis. Os resultados obtidos permitem verificar a existência de variação entre as progênies e cultivares quando as características são avaliadas de forma isolada. Não é indicado aplicar a seleção indireta nas características avaliadas, pois a produtividade média dos grãos não está fortemente associada às demais características. As progênies Arara planta 418 e Catucaí Amarelo 20/15 são indicadas para futuros cruzamentos, tendo em vista que esses materiais genéticos são mais produtivos que a testemunha Catuaí Amarelo IAC 66/69 e apresentam divergência genética entre si. Essas informações podem subsidiar os programas de melhoramento com finalidades específicas, ao possibilitar a escolha adequada de genitores.Item Field performance of coffee progenies and cultivars with specific resistance to rust(Editora UFLA, 2013-04) Costa, Joyce Cristina; Carvalho, Carlos Henrique de Siqueira; Matiello, José Braz; Almeida, Saulo Roque de; Carvalho, Samuel Pereira de; Baliza, Danielle PereiraThe aim of this research was to evaluate the yield and other agronomic characteristics of coffee progenies with specific resistance to rust. An experiment was carried out at the Experimental Farm of MAPA/Fundação Procafé (MAPA/ ProCoffee Foundation) in Varginha, MG, Brazil. The experiment was set up in January 2003 in a randomized complete block design with 12 progenies and two cultivars, five replicates and four plants per plot. The characteristics of average yield, maturation stage and screen analysis were asssessed. The data were subjected to analysis of variance and when there were significant effects from treatments, the means were compared by the Scott-Knott test. For the purpose of facilitating indirect selection, we sought to investigate the degree of association of the characteristics under study by means of the estimates of phenotypic correlation among the characteristics evaluated. Subsequently, genetic distances were estimated by the generalized Mahalanobis distance method to verify the variability among progenies. The results obtained allow us to verify the existence of variation among progenies and cultivars when the characteristics are evaluated separately. It is not recommended to apply indirect selection on the characteristics assessed because the average yield of coffee grains is not strongly associated with the other characteristics. The progenies Arara planta 418 and Catucaí Amarelo 20/15 are recommended for future crosses, considering that these genetic materials are more productive than the control Catuaí Amarelo IAC 66/69 and have genetic divergence. This information may help breeding programs for specific purposes upon enabling the appropriate choice of parents.