ABSTRACT Phosphorus is a major limiting nutrient for crops in tropical regions. In addition, another major challenge for the future agriculture will be to maintain water levels in the soil to ensure satisfactory crop development. This study inserted in this context aimed to evaluate the conditioning caused by phosphorus fertilization and water availability in the soil over the biomass production and nutritional efficiency of plants of crambe (Crambe abyssinica Hochst). To this end, the experiment was conducted in a greenhouse, with four levels of phosphorus fertilization and three levels of water availability, along of 45 days, in order to obtain information about the production of biomass, nutritional contents, and the patterns of the nutritional efficiency of crambe plants. The results show that increasing the phosphorus supply in the soil promotes greater biomass production in crambe plants. In addition, the increase in water availability and levels of phosphorus fertilization near the recommended level promotes greater nutritional efficiencies in absorb, translocate and use the phosphorus available in the soil.

RESUMEN La disponibilidad de agua y fósforo es una limitante para los cultivos en las regiones tropicales. El objetivo de este estudio fue evaluar el efecto de la fertilización fosfatada y la disponibilidad de agua en el suelo sobre la producción de biomasa y la eficiencia nutricional de las plantas de crambe (Crambe abyssinica Hochst). Las plantas fueron cultivadas en un invernadero, con cuatro niveles de fertilización de fósforo y tres niveles de disponibilidad de agua, para estudiar el comportamiento vegetativo entre emergencia y floración. Se evaluó la biomasa, contenido nutricional y patrones de eficiencia nutricional de las plantas. Los resultados muestran un aumento de biomasa al fertilizar con fósforo. Se observa un efecto sinérgico al aumentar la disponibilidad de agua y fósforo, mejorando la eficiencia en la absorción del fósforo disponible en el suelo.

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.

Crambe is a sensitive specie to exchangeable aluminum, it require a well-fertilized and corrected soil. The objective of this study was to understand the impact of aluminum presence, in different concentrations, in the substrate on the germination and development of crambe. The experiment was carried out as a randomized complete block design with a 5x2 factorial arrangement in four replicates. The five concentrations of Al3+ were 0, 15, 40, 80 and 120 mg dm-3 Al3+ and two temperatures (20 and 30 °C), with four replications. The relative growth rate, plant height, leaf number, total leaf area, specific leaf area, dry matter in each plant compartment (root, stem and leaf), leaf area ratio, stem mass ratio and leaf mass ratio were evaluate. Germination was favored by 20 ºC. The limitation on plant growth was greater as the concentration of aluminum increased, presenting losses in growth, as well of production of dry matter and leaf development, also causing changes in the patterns of biomass allocation between the plant compartments.

Crambe es una especie sensible al aluminio intercambiable que requiere suelos bien fertilizados y corregidos. El objetivo de este trabajo fue evaluar distintas concentraciones de aluminio en la germinación y desarrollo de crambe. El experimento para germinación se realizó con un diseño de bloques completos al azar con arreglo factorial de 5x2, con cuatro repeticiones. Las cinco concentraciones de Al3+ fueron 0, 15, 40, 80 y 120 mg dm-3 y las temperaturas de 20 y 30° C. El experimento para desarrollo de la planta se realizó con un diseño de bloques completos al azar con cinco concentraciones de Al3+ y cuatro repeticiones. Los parámetros evaluados fueron porcentaje de germinación, crecimiento de las plántulas y biomasa. Se analizó la tasa relativa de crecimiento, altura de planta, número de hojas, área foliar total, área foliar específica, materia seca en cada compartimento de la planta (raíz, tallo y hojas), razón de área foliar, razón de masa de raíz, tallo y hojas. El porcentaje de germinación aumentó a los 2 °C. La mayor concentración de aluminio afectó el crecimiento, producción de materia seca y desarrollo de hojas. Estos resultados sugieren que el cramble es sensible al aluminio intercambiable.

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.

The objective of this study was to evaluate the influence of pre-germination treatments and temperature on the germination of crambe seed (Crambe abyssinica Hochst). The completely randomized design was used in a 3 x 3 x 2 factorial (physical treatments x chemical treatments x temperature). The chemical treatments consisted of paper soaked in gibberellic acid (GA3), potassium nitrate (KNO3) and water. The physical treatments consisted of maintaining the seed intact, mechanical scarification and seed coat removal. Temperatures of 25 and 30 °C were used in the completely randomized design. The variables studied were germination speed index, germination percentage, seed length and seedling dry mass. In the studied conditions, the percentage and rate of germination, length and seedling dry weight of seeds of C. abyssinica Hochst were enhanced by removal of the integument, in soaking with GA3 at 25 °C.

Objetivou-se com o presente trabalho, avaliar a influência de tratamentos pré-germinativos e de temperaturas na germinação de sementes de crambe (Crambe abyssinica Hochst), em esquema fatorial 3 x 3 x 2 (tratamentos químicos x tratamentos físicos x temperatura). Sendo os tratamentos químicos: ácido giberélico (GA3), nitrato de potássio (KNO3) e água. E os tratamentos físicos: semente intacta, escarificação mecânica e a retirada do tegumento. Foram utilizadas as temperaturas de 25 e 30 °C em delineamento inteiramente casualizado. Estudou-se as seguintes variáveis: índice de velocidade e porcentagem de germinação, comprimento e massa seca das plántulas. Nas condições de estudo, a porcentagem e o índice de velocidade de germinação, o comprimento e a massa seca de plántulas das sementes de C. abyssinica Hochstforam incrementados com a remoção do tegumento, sob o umedecimento com GA3 na temperatura de 25 °C.

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.