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Se llevó a cabo un ensayo en el estado Trujillo, Venezuela, con el objetivo de evaluar el comportamiento morfoestructural de Albizia lebbeck, Leucaena leucocephala (ecotipo Trujillo) y Erythrina fusca en condiciones de vivero. Se utilizó un diseño completamente aleatorizado para mediciones repetidas en el tiempo y diez réplicas por especie. Las variables estudiadas fueron: altura de la planta; diámetro del tallo y de las ramas; número de hojas, ramas, raíces y nódulos totales; y longitud de la rama y de la raíz. Al final de la evaluación (18 semanas) no se observaron diferencias significativas entre L. leucocephala y E. fusca en la altura de la planta (45,2 y 51,0 cm), el diámetro del tallo (0,65 y 0,78 cm), el número de hojas (43 y 45) y de ramas (17 y 18) y la longitud de la raíz (32,1 y 36,5 cm). A. lebbeck sólo se destacó en el número de raíces (61) y de nódulos totales promedio (6). Los resultados permiten concluir que con la utilización de un sustrato alcalino en vivero, L. leucocephala y E. fusca exhibieron un comportamiento morfoestructural aéreo similar y superior que el de A. lebbeck; mientras que la albizia mostró mejores resultados en la morfoestructura radical.A trial was conducted in the Trujillo state, Venezuela, in order to evaluate the morphostructural performance of Albizia lebbeck, Leucaena leucocephala (Trujillo ecotype) and Erythrina fusca under nursery conditions. A completely randomized design was used for repeated measurements in time and ten replications per species. The studied variables were: plant height; stem and branch diameter; number of leaves, branches, roots and total nodules; and branch and root length. At the end of the evaluation (18 weeks) no significant differences were observed between L. leucocephala and E. fusca in plant height (45,2 and 51,0 cm), stem diameter (0,65 and 0,78 cm), number of leaves (43 and 45) and branches (17 and 18) and root length (32,1 and 36,5 cm). A. lebbeck only stood out for the number of roots (61) and average total nodules (6). The results allow concluding that with the utilization of an alkaline substratum in nursery, L. leucocephala and E. fusca showed a similar aerial morphostructural performance and higher than that of A. lebbeck; while albizia showed better results in root morphostructure.

Mediante el análisis descriptivo, de componentes principales y de clasificación automática (ACA), se llevó a cabo un experimento para caracterizar la composición nutricional del follaje de 53 accesiones del género Leucaena (37 L. leucocephala, 7 L. macrophylla, 5 L. lanceolata, 2 L. diversifolia, 1 L. glauca y 1 L. esculenta) establecidas en Matanzas, Cuba. Se determinó la composición química, los niveles de metabolitos secundarios y la degradabilidad ruminal. En general, las accesiones presentaron excelente composición química para ser utilizadas como suplemento en la alimentación de rumiantes (PC: 25,71 ±3,94%; FDN: 46,91 ±2,09%; cenizas: 7,48 ±0,96%; DMS: 60,24 ±9,90%). Los indicadores que explicaron mejor las variaciones entre las accesiones fueron los componentes de la fracción fibrosa y la polifenólica, la concentración de mimosina y la degradabilidad ruminal. Sin embargo, la fracción proteica, los niveles de materia seca, de fitatos, minerales y las cenizas presentaron pocas fluctuaciones. Mediante el ACA se identificaron tres grupos con características nutricionales diferenciadas entre sí. Las accesiones de L. macrophylla, L. diversifolia y L. esculenta presentaron mayor concentración de metabolitos secundarios y menor degradabilidad ruminal que las pertenecientes a L. leucocephala, L. lanceolata y L. glauca, las cuales mostraron los mejores resultados. La degradación de la MS, PC y FDN se vio afectada por los contenidos de fibra, polifenoles totales, taninos precipitantes y taninos condensados.Through the descriptive analysis, main component analysis and automatic classification, a trial was conducted to characterize the nutritional composition of the foliage of 53 accessions from the Leucaena genus (37 L. leucocephala, 7 L. macrophylla, 5 L. lanceolata, 2 L. diversifolia, 1 L. glauca and 1 L. esculenta) established in Matanzas, Cuba. The chemical composition, levels of secondary metabolites and ruminal degradability were determined. In general, the accessions showed excellent chemical composition to be used as supplement in ruminant feeding (CP: 25,71 ±3,94%; NDF: 46,91±2,09; Ash: 7,48 ± 0,96%; DMD: 60,24 ± 9,90%). The indicators that better accounted for the variations between accessions were the components of the fibrous and polyphenolic fraction, mimosine concentration and ruminal degradability. However, protein fraction, dry matter and phytate rates, minerals and ash showed little fluctuation. By means of the ACA three groups were identified with differentiated nutritional characteristics among themselves. The accessions of L. macrophylla, L. diversifolia and L. esculenta showed higher concentration of secondary metabolites and lower ruminal degradability than the ones belonging to L. leucocephala, L. lanceolata and L. glauca, which showed the best results. DM, CP and NDF degradation was affected by fiber, total polyphenol, precipitable tannin and condensed tannin contents.

Extra virgin olive oil (EVOO) is renowned for its numerous minor compounds, particularly phenols, which contribute to its health-promoting properties and commercial quality. The phenolic composition of EVOO largely relies on the initial phenolic content of the olive fruits, which represents, therefore, an important trait to be considered in olive breeding programs. However, only limited studies have been conducted so far to compare the relative influence of genotype and environment in the variability of this trait. For that reason, this study aims to assess the influence of genotype (cultivars ‘Arbequina’, ‘Coratina’, ‘Hojiblanca’, ‘Koroneiki’, ‘Martina’, and ‘Picual’) and environment (harvest date, season, and location) on the fruit phenolic content and composition. A wide general variability was obtained in the whole dataset, with total phenols ranging from 6019 to 38,380 μg/g. A stronger effect of the genotype than the environment was observed for total phenolic content (representing 76–90% of total sums of squares) and the different groups of compounds. Notably, significant variations were found among cultivars not only in the total phenol content but also in the percentage of individual compounds within each main phenolic group. Overall, taking into account the entire dataset available, a clear grouping of samples according to genotypes was observed. The results obtained highlight the prominent influence of the genotype (cultivar) over the environment and genotype–environment interactions on the phenolic content and composition in olive fruits; even when considering very contrasting environments as the Mediterranean and subtropical in the present work. These findings suggest the feasibility of breeding selection of new cultivars with distinctive phenolic content and composition.

The large amount of olive cultivars conserved in germplasm banks can be used to overcome some of the challenges faced by the olive growing industry, including climate warming. One effect of climate warming in olive is the difficulty to fulfill the chilling requirements for flowering due to mild winter temperatures. In the present work, we evaluate seven olive cultivars for their adaptation to high winter temperatures by comparing their flowering phenology in the standard Mediterranean climate of Cordoba, Southern Iberian Peninsula, with the subtropical climate of Tenerife, Canary Islands. Flowering phenology in Tenerife was significantly earlier and longer than in Cordoba. However, genotype seems to have little influence on the effects of the lack of winter chilling temperatures, as in Tenerife. This was found even though the cultivars studied had a high genetic distance between them. In fact, all the cultivars tested in Tenerife flowered during the three-year study but showed asynchronous flowering bud burst. ‘Arbequina’ showed an earlier day of full flowering compared with the rest of the cultivars. The results observed here could be of interest to refine the phenological simulation models, including the length of the flowering period. More genetic variability should be evaluated in warm winter conditions to look for adaptation to climate warming.

O principal objetivo deste trabalho foi identificar a associação entre o efeito combinado da atividade física e redução do tempo de tela com excesso de peso em adolescentes. Oestudo foi transversal com amostra composta por 613 adolescentes, com idade entre 15 a 18 anos residentes em município do nordeste do Brasil. A atividade física foi medida por meio do IPAQ (International Physical Activity Questionnaire), versão curta e o tempo de tela foi verificado por meio de duas questões sobre o tempo que, em média o entrevistado assistia televisão, jogava videogame, usava o celular ou o computador em um dia de semana normal e em um dia no final de semana. O poder preditivo e os pontos de corte do tempo de tela e da atividade física para o desfecho de interesse foram identificados por meio das curvas Receiver Operating Characteristic (ROC). Foram propostos ainda diferentes modelos de regressão logística tendo o excesso de peso como variável dependente. Em todos os modelos de análise foi fixada como referência a combinação pouca atividade física e muito tempo de tela. Utilizou-se intervalo de confiança (IC) a 95%. Em rapazes, a combinação atividade física e pouco tempo de tela em um dia do final de semana foi inversamente associada ao excesso de peso (OR = 0,31; 0,12-0,85). O efeito combinado da atividade física e redução do tempo sentado frente a TV, tela de computador e assemelhados em um dia no final de semana está inversamente associado ao excesso de peso em rapazes.

Many researches have concluded that the time spent in front of TV, computer and other screen-type devices is an important risk factor for overweight and obesity. The aim of this study was to identify the discriminatory power and to propose screen time cutoff points for overweight, obesity and abdominal obesity in adolescents. This household survey had cross-sectional design with sample of 613 adolescents aged 15-18 years living in a city in northeastern Brazil. The predictive power and cutoffs points of screen time for the outcomes of interest were identified by receiver operating characteristic curves (ROC). The study adopted 95% confidence interval (CI). Screen time during one day on the weekend was a good discriminator for the presence of overweight only among girls, area under the curve ROC = 0.59 (0.51 to 0.65). There were no areas under the ROC curve with statistical significance to discriminate obesity and abdominal obesity. Remain sitting for accumulated four hours per day during the weekend discriminates presence of overweight among girls (sensitivity = 60.9%, specificity = 52%). The long time spent in front of TV, computer and other screen-type devices on the weekend discriminate overweight in girls.

Se desarrolló un experimento en el estado Trujillo, Venezuela, con el objetivo de comparar el patrón de crecimiento y la distribución de biomasa de Albizia lebbeck, Leucaena leucocephala (ecotipo Trujillo) y Erythrina fusca durante 18 semanas en vivero. Las variables estudiadas fueron: tasa de crecimiento en función de la altura (TCA) y de la distribución de la MS (TCMS), así como el porcentaje de materia seca (MS) y el peso seco por planta de las fracciones (hojas, tallo, raíz). Se utilizó un diseño completamente aleatorizado para mediciones repetidas en el tiempo y diez réplicas por especie. Erythrina presentó la mayor TCA y TCMS promedio (3,7 mm/día y 94,8 mg/día), seguida por leucaena (3,1 y 81,3) y, por último, albizia (1,2 mm/día y 53,1 mg/día), respectivamente. Independientemente de la especie, el mayor porcentaje de MS promedio se observó en las raíces (31,9), seguido por el tallo (28,0) y las hojas (25,4). Se observó una mayor distribución de MS por planta en las hojas (3,9 g) y la raíz (3,1 g), comparados con el tallo (2,9 g). Se concluye que, para estas condiciones de aviveramiento, E. fusca presentó los mejores resultados; mientras que A. lebbeck necesitaría más tiempo para alcanzar las características deseables para su trasplante a campo.A trial was conducted in the Trujillo state, Venezuela, in order to compare the growth and biomass distribution pattern of Albizia lebbeck, Leucaena leucocephala (Trujillo ecotype) and Erythrina fusca for 18 weeks in nursery. The studied variables were: growth rate related to height (GRH) and DM distribution (GRDM), as well as dry matter percentage (DM) and dry weight per plant of the fractions (leaves, stem, root). A completely randomized design for measurements repeated in time and ten replications per species were used. E. fusca showed the highest average GRH and GRDM (3,7 mm/day and 94,8 mg/day), followed by L. leucocephala (3,1 and 81,3) and, lastly, A. lebbeck (1,2 mm/day and 53,1 mg/day), respectively. In dependently from the species, the highest percentage of average DM was observed in the roots (31,9), followed by the stem (28,0) and leaves (25, 4). A higher DM distribution per plant was observed in the leaves (3,9 g) and root (3,1 g) as compared to the stem (2,9 g). It is concluded that, for these nursery conditions, E. fusca showed the best results; while A. lebbeck would need more time to reach the desirable characteristics for its transplant to the field.