ABSTRACT Due to the possibility of enhancing the physiological responses by modulating the architecture of coffee trees, the objective of the study was to analyze the leaf gas exchanges and biomass allocation of Arabica coffee cultivated with different numbers of orthotropic stems. The experiment was carried out in a plantation located in Santa Teresa-ES, Brazil, cultivated with spacing of 2.5×1.0 m, using the cultivar Catuaí Vermelho IAC44. The gas exchange rates were monitored along stages of the phenological cycle (2014/2015), following a split-plot scheme, 3×3 (number of orthotropic stems per plant in three levels: 1, 2 and 3; and the phenological stages in three levels: flowering, fruit formation and maturation). The allocation of biomass in the plagiotropic branches was also analyzed during the phenological stage of fruit maturation. The management of the number of orthotropic stems affected the photosynthetic responses and biomass allocation of coffee trees. Under the studied conditions, cultivating the plants with two orthotropic stems created conditions which promoted the photosynthetic responses. Keeping more stems promotes the availability of leaves per amount of produced fruits in the plagiotropic branches, allowing the plant to sustain the production with less metabolic wearing.

The study objective was to determinate the concentration of aluminum that allow to distinguish genotypes of Jatropha for tolerance to this element, using the solution-paper method. For this study, seeds of four genotypes of Jatropha, were germinated at different Al concentrations (0, 15, 40, 80 and 120 mg L-1). After 14 days, the root length was measured for all treatments. It was observed that there are different tolerance levels for the genotypes. The root length decreased exponentially with the increase of the Al concentration. The solution-paper method allows the selection of genotypes of Jatropha in relation to aluminum tolerance and the concentration of 40 mg L-1 of Al is recommended to discriminate the tolerance of genotypes to this element.

El objetivo de la investigación fue evaluar el efecto de la concentración del aluminio en solución que mejor diferencia la tolerancia al aluminio en genotipos de Jatropha, utilizando el método papel-solución. Semillas de cuatro genotipos diferentes de Jatropha (CNPAE-248, CNPAE-301,CNPAE-308 y CNPAE-144) fueron germinadas en diferentes concentraciones de Al (0, 15, 40, 80 y 120 mg L-1) usando la técnica de papel-solución. Después de 14 días se midió el tamaño de la raíz primaria en todos los tratamientos. Los resultados aquí presentados muestran que hay un comportamiento diferente de los genotipos para la tolerancia donde el tamaño de la raíz primaria de estos disminuye exponencialmente en relación con el aumento de los niveles de Al. El método de papel-solución permite la selección de los genotipos de Jatropha en relación con la tolerancia al aluminio; recomienda utilizar la concentración de 40 mg L-1 de Al para discriminar diferencias en la tolerancia a este elemento.

Estudos de eficiência nutricional de fósforo, em cafeeiro conilon, são ferramentas importantes para contornar a elevada limitação que os baixos níveis naturais desse nutriente trazem aos cultivares dessa espécie. Objetivou-se, com este trabalho, estudar a eficiência nutricional e a resposta ao fósforo por clones de cafeeiro conilon. As plantas foram conduzidas durante 150 dias em vasos, contendo 10 dm³ de solo, em casa de vegetação. Utilizou-se o esquema fatorial 13 x 2, com três repetições, sendo os fatores: 13 clones que compõem o cultivar clonal "Vitória Incaper 8142" e dois níveis de adubação fosfatada (0 e 150% do recomendado de P2O5 para a cultura), em delineamento inteiramente casualizado. Os resultados indicam resposta diferenciada de produção de massa de matéria seca e de conteúdo de fósforo a cada nível de adubação fosfatada, para os clones de cafeeiro conilon e que os clones CV-04, CV-05 e CV-08 apresentam-se nutricionalmente eficientes e responsivos à adubação fosfatada.

Studies on nutritional efficiency of phosphorus in conilon coffee plants are important tools to unravel the high limitation that natural low levels of this nutrient in soil impose to these species cultivars. Therefore, this study aimed at evaluating the nutritional efficiency and the response to phosphorus of conilon coffee clones. Plants were managed during 150 days in pots containing 10 dm³ of soil, in greenhouse. A factorial scheme 13 x 2 was used, with three replications, being the factors: 13 clones constituting the clonal cultivar "Vitória Incaper 8142" and two levels of phosphate fertilization (0% and 150% of the P2O5 usualy recommended), in a completely randomized design (CRD). The results indicate a differentiated response of dry matter production and of phosphorus content on each level of phosphate fertilization for the conilon coffee clones and that CV-04, CV-05 and CV-08 clones are nutritionally efficient and responsive to the phosphate fertilization.

Apesar do controle químico da ferrugem do cafeeiro e a adubação nitrogenada serem amplamente pesquisado no Brasil, não existem trabalhos na literatura que apresentam esta interação em plantas de café conilon. Desta forma, objetivou-se estudar a interação entre o efeito da adubação nitrogenada e de ciproconazol+tiametoxam, no crescimento de mudas de café conilon, cultivar "Emcaper 8151 - Robusta Tropical", em ambiente controlado. Para isso, utilizou-se o delineamento experimental inteiramente casualizado, com quatro repetições, em esquema simples, com 13 níveis de combinações de nitrogênio e ciproconazol+tiametoxam. Os níveis de nitrogênio e ciproconazol+tiametoxam foram combinados seguindo modelo matricial Box Berard aumentada a 3(2k + 2k + 2k + 1). Os resultados mostram que as combinações do nível recomendado de ciproconazol+tiametoxam e de nitrogênio influenciaram negativamente as variáveis analisadas das plantas de café conilon, na condição de estudo.

Although the chemical control of coffee rust and the nitrogen fertilization are widely studied in Brazil, there are no documented studies that show this interaction in conilon coffee plants. Thus, the objective of this experiment was to study the interaction between the effects of nitrogen and cyproconazole+thiamethoxam in the growth of conilon coffee seedlings, cultivar "Emcaper 8151 - Robusta Tropical", in controlled environment. For this, a completely randomized design was used, with four replicates, simple layout, with 13 levels of combinations of nitrogen and cyproconazole+thiamethoxam. The levels of nitrogen levels and cyproconazole+thiamethoxam were combined following a Box Berard increased to 3 (2k + 2k + 2k + 1) matrix model. The results show that the combinations of the recommended level of cyproconazole+thiamethoxam and nitrogen influenced negatively the analyzed variables of the conilon coffee plants, in the studied conditions.

Com este trabalho, objetivou-se verificar a influência da aplicação de ciproconazol+tiametoxam, via solo, no crescimento de mudas clonais de cafeeiro conilon que compõem cultivar clonal 'Vitória Incaper 8142'. O experimento foi conduzido em vasos e sob condições de ambiente controlado. Utilizou-se delineamento inteiramente casualizado, com distribuição fatorial de 13x2, com quatro repetições, sendo os fatores: 13 clones que compõem a cultivar clonal 'Vitória Incaper 8142'; tratados e não tratados com ciproconazol+tiametoxam. Nas condições avaliadas, as mudas de todos os clones apresentaram, crescimento inferior e sintomas variados de fitotoxidade, influenciados pela aplicação via solo de ciproconazol+tiametoxam.

In order to assess the influence of the cyproconazole + thiamethoxam, into the soil, the growth of clonal coffee conilon comprising clonal cultivar 'Vitória Incaper 8142'. The experiment was conducted in pots and under greenhouse conditions. We used a completely randomized design with factorial distribution of 13x2 with four replications, being the factors: 13 clones that comprise the clonal cultivar 'Vitória Incaper 8142'; treated and untreated with cyproconazole + thiamethoxam. Evaluated conditions, the seedlings of all clones were lower and varied symptoms of phytotoxicity, influenced by the application via soil cyproconazole + thiamethoxam.

O crescimento e a produção de plantas de C. arabica, em função do porta-enxerto, foi avaliado em condições de campo, em Paula Cândido - MG. Utilizaram-se como enxerto quatro genótipos de C. arabica: as variedades Catuaí Vermelho IAC 15 e Oeiras MG 6851 e as progênies H 419-10-3-1-5 e H 514-5-5-3, e, como porta-enxerto, três genótipos de Coffea canephora Pierre ex A.Froenher: Apoatã LC 2258, Conilon Muriaé-1, sementes oriundas de um campo de recombinação entre os clones de variedade Robustão Capixaba (EMCAPA 8141) e o genótipo de C. arabica: Mundo Novo IAC 376-4, além da utilização de quatro pés-francos. A enxertia em cafeeiro pode influenciar o desenvolvimento das plantas, quando se compararam diferentes combinações enxerto/porta-enxerto com os respectivos pés-francos.Em plantas de cafeeiro enxertadas de seis anos, as combinações de enxertia Catuaí 15/Conilon, Oeiras/Apoatã, Oeiras/EMCAPA e H419/EMCAPA suplantaram os respectivos pés-francos na produção de café.

The effect of rootstocks on vegetative growth and yield of coffee plants (C. arabica) were evaluated under field condition at Paulo Cândio, Minas Gerais State, Brazil. It was tested four genotypes of C. arabica as grafts the varieties Catuaí Vermelho IAC 15 and Oeiras MG 6851 and the progenies H 419-10-3-1-5, H 514- 5-5-3 and three genotypes of C. canephora as rootstocks: Apoatã LC 2258, Conillon Muriaé-1 and recombination among clones of the variety Robustão Capixaba (EMCAPA 8141) and one genotype of C. arabica L.: Mundo Novo IAC 376-4. As a control it was wed non-grafted plants. Based on the results it could be concluded that plant development may was affected by grafting when non-grafted plants and graft/ rootstock combinations are compared. The grafting combinations Catuaí 15/Conilon, Oeiras/Apoatã, Oeiras/EMCAPA and H419/EMCAPA of 6 year, promoted increase in coffee yield, when compared to the respective non-grafted plant.