The objective of this study was to evaluate the nutritional efficiency of phosphorus in clones of conilon coffee, in greenhouse condition. A factorial design 13 x 4 was used, with three replications, and the factors being: 13 clones that compose the clonal cultivar "Vitória Incaper 8142" and four levels of phosphorus fertilization (0%, 50%, 100% and 150% of the recommended P 2 O 5 for the culture) in a completely randomized design (CRD). The cultivation consisted of a period of 150 days, then in each experimental unit, the values of dry matter and phosphorus content of the vegetative parts were obtained. The indices of nutritional efficiency (absorption, translocation and utilization) were calculated. The clones of conilon coffee showed different behavior for all variables at each level of fertilization with P 2 O 5 . The mass of dry weight, phosphorus content, and efficiency of phosphorus utilization of the clones increase linearly with the increase of P 2 O 5 . The efficiency of phosphorus absorption, depending on the levels of P 2 O 5 applied to the clones of conilon coffee, has set to a quadratic model. The translocation efficiency of phosphorus, depending on the levels of P 2 O 5 applied, is different for clones of conilon coffee, with a linear characteristic and also quadratic.

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The objective of this study was to evaluate the nutritional efficiency of phosphorus in physic nut (Jatropha curcas L.) genotypes, under controlled conditions. The experiment was arranged in a randomized block design, in a factorial scheme 10 x 2, using ten physic nut genotypes, two levels of phosphorus available in the soil (10 and 60 mg dm^-3), and four replications. Cultivation consisted of a period of 100 days, with vegetative growth being evaluated in each experimental plot, with the dry matter mass values, phosphorus contents in the vegetative parts, nutritional efficiency indices, and alpha parameter also being obtained. The results show that the physic nut genotypes present greater vegetative growth, dry matter mass accumulation, P content, absorption efficiency and translocation at the high level of phosphorus available in the soil. Genotype CNPAE-C2 is the most efficient and responsive to phosphoric fertilization

The use of supplementary irrigation to sustain the plantation during moments of severe water stress or moments of high water demand is becoming almost a norm to keep sustainable crops, especially due to the climate changes and the high frequency in which climate extremes are occurring lately. The objective of this study was to evaluate the agronomic performance and expression of genetic variability among genotypes of Coffea arabica L. cultivated in farming systems with different levels of water supply, focusing on rainfed or supplementary irrigated systems. The experiment was developed in competition field, testing 8 genotypes of C. arabica L. in rainfed or supplementary irrigated systems. The growth and production were evaluated during 2 consecutive cycles (2014-2015 and 2015-2016). Among the growth gains, it was observed large gains in coffee yield, but the magnitude of the gains varied among genotypes. For crop yield, for example, Paraíso MG/H 419-1 presented 136% gain, while Oeiras MG-6851 was capable of yielding as much more coffee in rainfed conditions than in irrigated system. The expression of variability for some agronomic traits (such as coffee yield, canopy size, growth rate, and number of new buds) may be intensified by the supplementary water supply, which promotes gains in production and growth, increases the magnitude of variation among genotypes and allows to identify different patterns for selection, which may not be observed in the rainfed systems.

ABSTRACT. The present study was developed to respond to the need for an increase in crop yield in the mountain region of Caparaó (southern Espírito Santo State, Brazil), an area of traditional coffee production. This study aimed to analyze the diversity and characterize the crop yield of genotypes of Coffea arabica L. with potential for cultivation in high plant density systems. In addition, it also aimed to quantify the expression of agronomic traits in this cultivation system and provide information on the genotypes with the highest cultivation potential in the studied region. The experiment followed a randomized block design with 16 genotypes, four repetitions, and six plants per experimental plot. Plant spacing was 2.00 x 0.60 m, with a total of 8333 plants per hectare, representing a high-density cultivation system. Coffee plants were cultivated until the start of their reproductive phenological cycles and were evaluated along four complete reproductive cycles. Genotypes with high crop yield and beverage quality, short canopy, and rust resistance were selected. C. arabica genotypes showed variability in almost all characteristics. It was possible to identify different responses among genotypes grown in a high plant density cultivation system. Although the chlorophyll a content was similar among genotypes, the genotypes Acauã, Araponga MG1, Sacramento MG1, Tupi, and Catuaí IAC 44 showed a higher chlorophyll b content than the other genotypes. Among these, Sacramento MG1 also showed high leafiness and growth of vegetative structures, whereas Araponga MG1, Pau-Brasil MG1, and Tupi showed high fruit production. In addition, Araponga MG1 had also a higher and more stable crop yield over the years.

This study investigated the severity of leaf rust and brown eyespot in genotypes of Coffea arabica L. cultivated with high plant density in the region of Caparaó-ES. The experiment was conducted in a competition field, cultivated with high plant density (8333 plants per hectare), following a randomized block design, with 16 genotypes and four replications. The plants were evaluated during consecutive harvests to study two complete reproductive cycles (from 2010 to 2012). Data were obtained for the phenologicalstages of flowering, graining, maturation and vegetative rest of each cycle. The severity of leaf rust (Hemileia vastratrix) and brown eyespot (Cercospora coffeicola) was evaluated using descriptive scales. It was observed that the genotypes are able to keep a considerable level of resistance to the leaf rust and brown eyespot when cultivated with increased density. The genotypes presented variability regarding the severity of the leaf rust and brown eyespot, indicating the existence of differential levels of resistance between them. For cultivation with high plant density, the genotypes Katipó, Paraíso MG H419-1, H419-3-3-7-16-4-1-1

Efficiency of absorption and utilization of boron, zinc, copper and manganese in grafted coffee seedlingsStudying nutritional efficiency of grafted coffee plants is important for the selection of graft/ rootstock combinations, aiming to achieve better plant development and yield. The objective of this work was to evaluate the genetic differences for B, Zn, Cu and Mn absorption and utilization efficiencies of grafted coffee seedlings. The experiment was conducted with seedlings planted in 20 L pots with a substrate consisting of soil, sand, and manure in the proportion of 3:1:1, in which they kept for 18 months, until harvest. Four genotypes of Coffea arabica L. were used as grafts: cultivars Catuaí Vermelho IAC 15 ('Catuaí 15) and Oeiras MG 6851 ('Oeiras'), and hybrids H419-10-3-4-4 ('H419') and H514-5-5-3 ('H514'). O estudo da eficiência nutricional de plantas enxertadas de cafeeiro é importante para a seleção de combinações enxerto/porta-enxerto, visando atingir melhor desenvolvimento e produção. Este trabalho teve como objetivo avaliar as diferenças na eficiência de absorção e utilização de B, Zn, Cu e Mn em mudas enxertadas de cafeeiro. O experimento foi conduzido em vasos de 20 litros contendo como substrato terra, areia e esterco na proporção de 3:1:1, onde as plantas permaneceram por um período de 18 meses. Utilizaram-se como enxerto quatro genótipos de Coffea arabica L.: os cultivares Catuaí-Vermelho IAC 15 ('Catuaí 15') e Oeiras MG 6851 ('Oeiras') e os híbridos H419-10-3-4-4 ('H419') e H514-5-5-3 ('H514') do programa de melhoramento da EPAMIG/UFV. Como porta-enxerto foram empregados cinco progênies de famílias de meio-irmãos de clones de Coffea canephora Pierre ex Froenher cv. Conilon: ES 21, ES 36, ES 26, ES 23 e ES 38 do programa de melhoramento de café robusta do Incaper. O delineamento experimental foi inteiramente casualizado, com 24 tratamentos e três repetições, sendo quatro pés-francos e 20 combinações de enxertia. A eficiência nutricional das plantas variou conforme a combinação enxerto/porta-enxerto. O cultivar Oeiras não foi beneficiado por nenhuma enxertia, apresentando redução da produção total de matéria seca em todas as combinações comparativamente ao respectivo pé-franco. O cultivar Catuaí 15 foi mais eficiente na produção de matéria seca e utilização de B e Zn quando combinado com os materiais genéticos de conilon ES 26 e ES 23. Palavras-chave:Café, enxertia, eficiência nutricional, micronutrientes.

Coffea canephora shows considerable variability for several agronomic traits, including nutritional efficiency. Beside the intrinsic nutritional efficiency of a genotype, the availability of water in the soil is another factor that can cause different responses, which suggests the possibility of selection of genotypes to enhance the nutritional efficiency under different scenarios, such as plantings in areas with low natural fertility or subjected to drought. We evaluated the genetic diversity of genotypes of C. canephora that compose the cultivar "BRS Ouro Preto", the first available clonal cultivar recommended for Rondonia State, based on parameters of nutritional status of the plants subjected to cultivation under conditions of abundant water supply or subjected to water deficit. To this end, the experiment was developed with two trials where the 15 genotypes of this cultivar were cultivated in a greenhouse, under conditions of abundant water supply or subjected to water deficit. The trials followed a completely randomized design, with four replications and the mineral status of the plants was evaluated based on the content of N, P, K, Ca, Mg and S of their green tissues. The genotypes ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 18 (2): gmr18300 L.C.T. Starling et al. 2presented high variability for these nutritional parameters, making it possible to identify distinct patterns and to group them according to their nutritional status. Variability was affected by drought, showing that the water supply can cause changes in patterns of nutritional status and affect the clustering of genotypes. The genotypic effect surpassed the environmental influence for most mineral parameters, resulting in a desirable scenario for a possible selection to enhance nutritional efficiency, for both irrigated and rainfed systems, within the group of genotypes that already present high yield in Rondonia state.