The objective of this work was to control the purity level of canephora coffees (Conilon coffee) from the state of Espírito Santo (Brazil), as a function of the addition of grounds produced by the coffees themselves using a portable microspectrometer in the infrared region. (microNIR), associated with chemometric tools. The PCA model grouped the coffees according to the level of adulterant in the samples and showed that the presence of moisture and polysaccharides is important for the discrimination between pure and adulterated samples. PLS-DA and SIMCA classification models were built with commercial samples and resulted in the discrimination of authentic and non-authentic samples with accuracy values above 90% and 82% for PLS-DA and SIMCA, respectively. The quantification results presented by the PLS model were satisfactory for all models, reaching the best results at 75 °C with RMSEP values of 6.13 wt%, R2p = 0.9917; and LOD in the range of 5.6-8.9 wt%; LOQ = 17-26.8 wt%, according to IUPAC; relative standard deviation for repeatability of 1.0 and 1.7 wt%; and intermediate precision of 3.4 and 1.1 wt% for low (<10 wt%) and high (≈ 90 wt%) levels of adulterants, respectively. Therefore, this work represents the first exploratory study to analyze adulterations with coffee grounds by portable NIR, demonstrating the potential of the equipment against this type of adulteration.

RESUMO Informações obtidas a partir de estudos de variabilidade espacial e do Sistema Integrado de Diagnose e Recomendação (DRIS) poderão contribuir para o melhor entendimento da relação entre o balanço de nutrientes e os fatores que limitam a produtividade das culturas. Este estudo mostra que plantas equilibradas nutricionalmente podem estar associadas à baixa produtividade em café Conilon (Coffea canephora). O estudo foi realizado em uma lavoura altamente produtiva de café Conilon em São Mateus, ES. Foi estabelecida uma grade amostral com 100 pontos, cada ponto relacionado a uma planta. Vinte pares de folhas de cada planta foram coletados de ramos produtivos compondo uma amostra para análise nutricional. A incidência da ferrugem (Hemileia vastatrix), a presença da broca do café (Hypothenemus hampei), e características físicas do solo também foram coletadas para cada planta amostrada. O DRIS e o Índice de Equilíbrio dos Nutrientes (IEN) foram calculados e, com os dados de produtividade, foram caracterizados utilizando estatística descritiva. Foram criados mapas com a distribuição espacial do IEN, produtividade, areia total e incidência de ferrugem e da broca do cafeeiro. Verificou-se baixa relação entre equilíbrio nutricional e produção no café Conilon, sugerindo que fatores não nutricionais também influenciaram na produtividade das plantas. Nas áreas dos mapas com alto IEN, o balanço nutricional da planta foi o principal fator limitante da produção, pois a maioria das plantas nessa área produziu menos que a produtividade média das plantas amostradas. O uso de uma ferramenta geoestatística combinada com o IEN resultou em melhor compreensão da relação entre variáveis nutricionais e não nutricionais sobre a produtividade de café Conilon.

ABSTRACT Information obtained from studies of spatial variability and the Diagnosis and Recommendation Integrated System (DRIS) may contribute to understanding better the relationship between mineral nutrient balance and factors that limit the crop yield. This study shows that nutritionally balanced plants may be associated with low productivity in Conilon coffee fields. The study was carried out on a highly productive Conilon coffee (Coffea canephora) field, in São Mateus, state of Espírito Santo, Brazil. A sample grid was established with 100 points, each point linked to one plant. Twenty pairs of leaves from each plant were collected from productive branches to create a sample for nutritional analysis. The rust incidence (Hemileia vastatrix), the presence of the coffee borer (Hypothenemus hampei), and the physical characteristics of the soil were evaluated in each sampled plant. DRIS and Nutrient Balance Index (NBI) were calculated, and from the yield data, they were characterized using descriptive statistics. Maps were created showing the spatial distribution of the NBI, yield, total sand, and incidence of rust and coffee borer. It was verified the low relationship between nutritional balance and yield in Conilon coffee, suggesting that non-nutritional factors also influenced plant production. In areas of the maps with high NBI, the plant’s nutritional balance was the main limiting factor of production, since most plants in this area produced less than the average productivity of the plants sampled. The use of a geostatistics tool combined with the NBI resulted in better understanding of the relationship between nutritional and non-nutritional variables on the Conilon coffee yield.

RESUMO A fertilidade do solo é um fator decisivo para o rendimento das culturas agrícolas e a sua distribuição e correlação espacial, e podem alterar significativamente a produtividade média em uma área cultivada. Objetivou-se no presente trabalho estudar a variabilidade e correlação espacial dos micronutrientes ferro (Fe), cobre (Cu), manganês (Mn), zinco (Zn), da matéria orgânica (MO) e da produtividade em uma área cultivada com macadâmia. O estudo foi desenvolvido em um Latossolo Amarelo distrocoeso, cultivado há 20 anos com macadâmia no município de São Mateus, ES. A malha instalada foi de 144 x 140 m com 100 pontos e com distância mínima de 5 m, onde foi coletada uma amostra composta de solo na profundidade de 0-0,20 m, utilizada para análise química do Fe, Cu, Mn, Zn e da MO. A colheita da macadâmia foi realizada no período de fevereiro a junho de 2015, colhendo-se os frutos na projeção da copa da planta. Os dados foram submetidos à análise geoestatística através do ajuste de semivariogramas experimentais e o método de krigagem foi aplicado para mapear os padrões espaciais dos nutrientes e da produtividade. Todos os atributos em estudo apresentaram estrutura de dependência espacial (forte e moderada). A MO teve correlação positiva com os micronutrientes, e somente o Zn teve correlação positiva com a produtividade. Zn e Mn obtiveram semivariogramas cruzados que explicaram os mapas observados, enquanto o Fe obteve tendência contrária à produtividade da macadâmia.

ABSTRACT Soil fertility is the key to agricultural production. The spatial correlation and location of nutrients may significantly affect the yields. The objective of this work was to evaluate the variability and spatial correlation of iron (Fe), copper (Cu), manganese (Mn), zinc (Zn), and organic matter (OM) with macadamia nut yield. The study was conducted in an Oxisol cultivated for 20 years with macadamia nut in São Mateus, state of Espírito Santo, Brazil. A 100 point grid was used comprising an area of 144 × 140 m with a minimum distance between points of 5 m, in which a single composite soil sample was collected from 0-0.20 m layer for chemical analysis of Fe, Cu, Mn, Zn and OM. Nuts under the canopy’s projection were harvested from February to June, 2015. The data were evaluated by geostatistical analysis using semivariograms, and kriging was used to map spatial distributions of nutrients and nut yield. All evaluated attributes showed strong or moderate spatial dependence structure. The OM was correlated positively with micronutrients, but only Zn was positively correlated with nut yield. Crossed semivariograms adequately explained the maps of Zn and Mn; and Fe showed opposite tendency for macadamia nut yield.

Abstract The morphoagronomic characterization of 12 genotypes of M. esculenta was performed during the 2013/2014 and 2014/2015 crop years. The 12 genotypes were planted in a randomized block design, with four replicates per genotype. Number of tuberous roots per plant, weight of tuberous roots, root yield, total plant weight, harvest index, plant height, height of first branch, number of shoots, stem diameter, number of buds, leaf dry weight and petiole length were evaluated. Genotypes “Camuquem” and “Goiás” were the most productive, and “Amarela” and “Gema de Ovo” were the most divergent. Seventy percent of genetic diversity was due to petiole length (22.86%), root yield (19.20%), weight of tuberous roots (14.89%) and number of buds (13.72%). Overall, the present results indicate a broad genetic basis for the evaluated genotypes, so that such genetic variation benefits the plant breeding for future scenarios Further studies of the evaluated genotypes should be performed under environmental limitations, using biochemical and molecular tools to identify markers for genetic improvement.

Abstract Knowledge of the genetic variability of a population is essential to guide its preservation and maintenance in addition to increasing the efficiency of genetic breeding programs. On this basis, this study was conducted to evaluate the genetic diversity of Coffea canephora genotypes using multivariate statistical procedures applied to a set of morpho-agronomic variables. The materials employed in this study constitute a crop located in Vila Valério - ES, Brazil, where the genotypes are arranged in a randomized-blocks experimental design with four replicates. Significant differences were detected by the F test at the 1% or 5% probability levels among the genotypes for all evaluated traits, demonstrating heterogeneity of genetic constitution in the studied population, which is favorable to breeding, as it indicates the possibility to identify superior and divergent individuals. Based on the generalized Mahalanobis distance, the most divergent combinations were obtained between genotypes 23 and 10 (256.43) and 23 and 17 (250.09). The clusters formed by Tocher’s optimization and the UPGMA hierarchical method agreed, both similarly grouping the genotypes into three clusters. Of the analyzed traits, mature fruit weight (19.08%), yield (15.50%), plant diameter (12.42%), and orthotropic-shoot internode length (10.94%) were the most efficient to explain the dissimilarity among the genotypes.

RESUMO Objetivou-se, no presente estudo, caracterizar a variabilidade espacial dos atributos relacionados à acidez do solo, a necessidade de calagem e a produtividade de pimenta-do-reino sob um Latossolo Amarelo. O estudo foi realizado em uma lavoura de pimenta-do-reino, no município de São Mateus, ES. A área experimental possui dimensões de 100 x 120 m na qual demarcou-se uma malha com 126 pontos. Em cada ponto amostral foram coletadas três subamostras de solo na projeção da copa da pimenteira-do-reino compondo uma amostra na profundidade de 0-0,20 m. A produtividade da lavoura foi estimada por meio da colheita das três plantas circunvizinhas a cada ponto amostral. Os resultados obtidos foram submetidos à análise da estatística descritiva e à análise geoestatística. O mapa da necessidade de calagem possibilitou a delimitação das zonas homogêneas de taxas de calcário a serem aplicadas ao solo. Os modelos matemáticos ajustados aos semivariogramas demonstraram que todas as variáveis em estudo apresentaram estrutura de dependência espacial. O conhecimento da variabilidade espacial associada à definição de zonas homogêneas pode ser usado para aumentar a eficiência de aplicação de calcário.

ABSTRACT Studies aimed at determining homogeneous zones and the spatial variability of soil characteristics may improve the efficiency of agricultural input applications. The purpose of this study was to determine homogeneous zones for liming applications and to characterize the spatial variability of characteristics related to soil acidity and productivity in an Oxisol cultivated with black pepper (Piper nigrum L.). This study was carried out in São Mateus, state of Espírito Santo, Brazil. The experimental site was 100 x 120 m. A grid with 126 sampling points was established. Three soil sub-samples were collected at each sampling point in the black pepper canopy areas, at a 0-0.20 m depth. Crop productivity was estimated by harvesting the three plants neighboring each sampling point. Descriptive statistics and geostatistical analyses were performed. Homogeneous management zones were defined based on map of liming needs. Mathematical models adjusted to semivariograms indicated that all of the studied variables exhibited spatial dependency. An analysis of the spatial variability together with the definition of homogeneous zones can be used to increase the efficiency of soil liming.

Conduziu-se um experimento de campo sob sistema plantio direto (SPD) e sistema de plantio convencional (SPC) para avaliar a produção de massa seca, a quantidade de N e a taxa de decomposição de crotalária (Crotalaria juncea) e sorgo forrageiro (Sorghum bicolor L.), e seus efeitos na produtividade do feijoeiro comum (Phaseolus vulgaris L.). O sistema de manejo do solo não influenciou na produtividade de massa seca das plantas de cobertura do solo; contudo, o sorgo produziu 60% mais massa seca que a crotalária. O maior acúmulo de N foi observado sob SPD, 45% a mais que sob SPC; entretanto, não houve diferença entre as plantas de cobertura do solo. A taxa de decomposição da palhada sob SPD foi 50% menor do que sob SPC e, até os 28 dias, a decomposição da crotalária sob SPC foi mais rápida que a do sorgo. A produtividade de grãos da cultura do feijoeiro comum foi 40% maior em SPD em comparação com o SPC apresentando alta correlação com a quantidade de N acumulada pelas plantas de cobertura do solo. Sob as condições do Cerrado Goiano, o SPD promove maior acúmulo de N e menor taxa de decomposição das plantas de cobertura do solo, promovendo a maior produtividade da cultura do feijoeiro comum, comparado ao SPC.

A field experiment was carried out under no-tillage system (NT) and conventional tillage (CT) to assess the dry mass production, N accumulation and the decomposition rate of crotalaria (Crotalaria juncea) and sorghum (Sorghum bicolor L.), as well as, their effects on the grain yield of common bean (Phaseolus vulgaris L.). Results showed that soil management had no effect on the dry mass production of cover crop, however, the sorghum produced 60% more dry mass as compared with crotalaria. The largest N accumulation was observed under NT, which showed 45% more N than CT, however, no statistical difference between cover crops was observed. The straw rate decomposition under NT was 50% lower than under CT and, until 28 days, the decomposition of crotalaria under CT was faster than sorghum. The common bean grain yield was 40% higher under NT as compared with CT and it showed high correlation with N amount accumulated by the cover crops. Under Cerrado condition of Goiás state, NT promotes greater N accumulation and lower decomposition rate of the cover crops, leading to greater grain yield of common bean as compared with CT.