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The development of Coffea canephora cultivars is based on the characterization of genotype × environment interaction, which is interpreted to quantify the differential behavior of clones at different cultivation sites. The objective of this research was to study the genotype x environment interaction aiming to select clones of broad and specific adaptation to different environments of the Western Amazon. Twelve clones with hybrid characteristics of the botanical varieties Conilon and Robusta and four open pollinated clones, had their performance evaluated in comparison with four controls. The genotype × environment interaction was interpreted based on the environmental quality index, the non-parametric estimator of Lin and Binns, 1988 and on the dispersion of the centroid method. Effects of the genotypes, environment, and genotype × environment interaction were all significant (p<0.01). The environmental quality index (Ij) classified three environments as favorable for coffee production. In terms of the Lin and Binn’s estimator (Pi), hybrid genotypes 16, 10, 13, 09 and 14 presented lower Pi indices than others, and were classified as being more stable. Five clones of low adaptability, seven clones of specific adaptability to favorable or unfavorable environments and two clones of broad adaptability to all environments were identified interpreting the dispersion of the centroid method.

The evaluation of morphological characters related to the hulled coffee yield subsidizes the selection of <em>Coffea canephora</em> plants that combine a set of favorable traits. The aim of this study was to evaluate the direct and indirect effects of agronomic traits on the production of hulled coffee to subside the plant selection. To this, nine morphological descriptors were evaluated of 130 clones of the botanical varieties Conilon and Robusta over two crop years in the experimental field of Embrapa, in the municipality of Ouro Preto do Oeste, state of Rondônia (RO). To quantify the genetic variability the path analysis and the Scott Knott cluster test were used. The effect of genotype x year interaction was significant for eight of the nine characteristics analyzed. The genotypes were clustered in three to five classes, subsidizing the establishment of a scale to evaluate the variability of this genetic resource. Pathway analysis indicated that the number of plagiotropic branches and the number of rosettes per productive branch were the traits that exhibited the greatest direct effect on hulled coffee yield. These results show that it is possible to select plants with complementarity traits which favor a higher production of hulled coffee.

. In relation to resistance of orange rust, most of the genotypes were resistant to disease, and 75% of the genotypes did not present any type of infection symptoms. Among the susceptible genotypes, there was a variation between 1 and 15% in the degree of lesion intensity.

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RESUMOEntre as diversas espécies de café identificadas, o Coffea arabica e o Coffea canephora, são as cultivadas comercialmente de maneira significativa. Na região Amazônica a principal espécie cultivada é o C.canephora que apresenta naturalmente duas variedades botânicas distintas o Conilon e o Robusta. Essas variedades possuem diferentes características em relação ao tamanho e a forma do grãos que são classificados de acordo com a retenção em peneiras com crivos de diferentes diâmetros. O objetivo desse trabalho foi quantificar ao longo de duas safras a peneira média (PM) e o percentual de grãos moca (PGM) de C.canephora. Para isso foram coletadas, amostras de 300 gramas de café de 112 clones, das variedades botânicas Conilon (68) e Robusta (18) e de híbridos intervarietais (26), provenitente do campo experimental da Embrapa Rondônia do município de Ouro Preto do Oeste -RO. Peneiras de crivos oblongos, de numeração 9 a 13 foram utilizadas para caracterizar os grãos tipo moca e as circulares de 12 a 19 para os grãos tipo chato. Observou-se que a PM não alterou sua média de um ano para o outro (14,75), diferente do PGM que apresentou média de 32,5 no 1º ano e 54,01 no 2º ano. A PM é uma característica que foi pouca influenciada pelo ambiente em comparação com o PGM que apresentou uma baixa correlação ao longo do tempo. As variedades botânicas apresentam expressiva diversidade genética para PM que subsidia a seleção de novas cultivares que reúnam uma série de característica favoráveis. PALAVRAS-CHAVE: Melhoramento genético, Qualidade, rondônia.

Introdução: O estado de Rondônia se destaca como tradicional produtor de café, sendo o segundo maior produtor brasileiro de C. canephora. No melhoramento genético de C. canephora, a seleção de plantas de elevada peneira média está associada à bebida de qualidade superior. Objetivos: O objetivo desse estudo foi avaliar a variabilidade genética de clones de C. canephora para o tamanho dos grãos, mensurado a partir da avaliação da peneira média (PM). Materiais e Métodos: Para isso, foi conduzido ao longo de dois anos agrícolas experimento no campo experimental da Embrapa no município de Ouro Preto do Oeste-RO, para a avaliação da peneira média de 130 genótipos (clones) com características das variedades botânicas Conilon, Robusta e híbridos intervarietais. O delineamento experimental utilizado foi de blocos ao acaso, com quatro repetições de quatro plantas por parcela. Resultados: Não houve resultados significativos para a interação clones X anos, indicando uma maior consistência no comportamento das plantas ao longo do tempo. Porém foram observadas diferenças significativas para o tamanho dos grãos entre os genótipos avaliados, possibilitando selecionar genótipos superiores. Conclusão: Os genótipos agruparam-se em cinco classes de acordo com o teste de média, subsidiando a caracterização de um gradiente de variabilidade da característica avaliada ABSTRACTIntroduction: Coffea canephora accounts for approximately 35% of the world's coffee production. The state of Rondônia stands out as a traditional coffee producer, being the second largest Brazilian producer of C. canephora. In the classical genetic improvement of C. anephora, the selection of plants of high average sieve is associated with a drink of superior quality. Objectives: The objective of this udy was to evaluate the genetic variability of Coffea canephora clones for the agronomic medium sieve (PM). Materials and Methods: The experiment was conducted in the experimental field of Embrapa, municipality of OuroPreto do Oeste-RO, located at coordinates 10º44'53 "S and 62º12'57". One hundred thirty genotypes (clones) of botanical characteristics Conilon, Robusta and intervarietal hybrids were evaluated in the agricultural years 2013-2014 and 2014-2015. The experimental design was a randomized block design with four blocks and four plants per plot, spacing 3.5 x 1.5 meters between plants. Results: Significant difference was found for the grain size. According to the F test, at 5% probability, the genotypes were grouped into five classes according to the mean test. Conclusion: The results obtained subsidized the characterization of a variability gradient of the evaluated trait.