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Ítem Mitochondrial DNA variation of Apis mellifera iberiensis further insights from a large-scale study using sequence data of the tRNAleu-cox2 intergenic region(Springer Nature, 2017-02-15) Chávez Galarza, Julio César; Garnery, Lionel; Henriques, Dora; Neves, Cátia José; Loucif Ayad, Wahida; Johnston, J. Spencer; Pinto, María AliceA large-scale survey of the Iberian honey bee (Apis mellifera iberiensis) diversity patterns, using sequence data of the tRNAleu-cox2 mitochondrial DNA (mtDNA) region, demonstrates that earlier studies based on the DraI test missed significant components of genetic variation. Based on results from this survey, existing haplotype names were revised and updated following a nomenclature system established earlier and extended herein for the intergenic region. A more complete picture of the complex diversity patterns of IHBs is revealed that includes 164 novel haplotypes, 113 belonging to lineage A and 51 to lineage M and within lineage A and 69 novel haplotypes that belong to sub-lineage AI, 13 to AII, and 31 to AIII. Within lineage M, two novel haplotypes show a striking architecture with features of lineages A and M, which based on sequence comparisons and relationships among haplotypes are seemingly ancestral. These data expand our knowledge of the complex architecture of the tRNAleu-cox2 intergenic region in Apis mellifera and re-emphasizes the importance of Iberia as a source of honey bee mtDNA diversity.Ítem Selección de especies y sitios para plantaciones forestales; éxitos y fracasos(Instituto Nacional de Innovación Agraria - INIA, 2015) Vásquez Carballo, WilliamLos factores a considerar en la selección de especies y sitios para plantaciones forestales son: 1. Objetivo o propósito de la plantación. Uso doméstico, Uso Industrial, o Protección del Medio o combinación; 2. Especies disponibles: nativas o exóticas 3. Características del sitio. Necesidades del árbol, factores del sitio, factores climáticos, climas y especies, factores edáficos. 4. Mercados y precios .Ítem Incorporación de nitrógeno para mejorar la eficiencia de uso del cultivo de arroz (Oryza sativa L.) en La Libertad, Perú(Universidad Católica de El Salvador, 2019-09-20) Heros Aguilar, Elizabeth; Soplín Villacorta, Hugo; Sosa Peralta, GuillermoEl mejoramiento de la eficiencia de uso de nitrógeno reduciría el consumo de fertilizantes nitrogenados y contribuiría a la preservación del ambiente y al desarrollo de sistemas de producción sostenibles. Para mejorar la eficiencia de uso, se realizó un experimento en el valle del distrito de Jequetepeque, provincia de Pacasmayo, departamento de La Libertad en Perú, para identificar la forma de aplicación y los niveles de nitrógeno más adecuados para optimizar la eficiencia y disminuir las pérdidas que se originan por el mal manejo del nitrógeno. Se evaluaron tres formas de aplicación del fertilizante nitrogenado (urea): Forma 1: 100% incorporado en suelo seco; Forma 2: 50% incorporado en suelo seco + 50% al voleo al inicio del primordio floral en lámina de agua; y Forma 3: Voleo tradicional aplicando la mitad del nitrógeno a los quince días después del trasplante en lámina de agua y el 50% restante al inicio del primordio floral al voleo en lámina de agua. Los niveles utilizados fueron: 120, 240 y 320KgNha-1 y un testigo 0. El rendimiento en grano obtenido varió de 5.67 a 4.88tha-1, para formas y de 7.36 a 5.34tha-1, para niveles de nitrógeno. La estimación de la eficiencia de uso de nitrógeno a través de los indicadores de eficiencia agronómica, eficiencia fisiológica y factor parcial de productividad, identificaron que la forma 2 tuvo la mejor respuesta.Ítem L’anthracothèque de Bordeaux : une collection de référence pour l’identification taxonomique des charbons de bois macrofossiles provenant des Landes de Gascogne et de leur périphérie(Université de Bordeaux, 2013-06-30) De Lafontaine, Guillaume; Amasifuen Guerra, Carlos Alberto; Ducousso, AlexisLes macrofossiles de charbon de bois enfouis dans le sol sont employés en paléoécologie pour étudier l’histoire écologique des communautés végétales ligneuses. L’approche moderne employant les charbons enfouis dans le sol (pédoanthracologie) s’appuie sur l’identification taxonomique sur la base de l’anatomie du bois à l’aide de guides d’identification et d’une collection d’échantillons de référence (anthracothèque) provenant de la région étudiée. Il n’existe pas encore de collection de référence pour les Landes de Gascogne et leur périphérie. Nous profitons d’une étude pédoanthracologique focalisée sur cette région pour établir une telle collection de 30 échantillons de référence provenant de 29 espèces ligneuses communes dans la région. Nous documentons une approche méthodologique simple et économique pour produire les échantillons de référence.Ítem Nueva variedad de avena (Avena sativa L.) multipropósito; resiliente al cambio climático y de ciclo corto(Universidad Nacional de Trujillo, 2020-12-30) Alejos Rivera, Juan; Aedo Palacios, Julio; Guerra Galdo, EvaCon el objetivo de obtener variedades de avena forrajera para alimentación de ganado, la EEA Andenes del INIA en el año 2019 obtiene la nueva variedad denominada INIA 908 - Mellicera. En las campañas agrícolas de 2013 a 2016 se evaluó con la línea L8 y variedad testigo INIA 903 - Tayko Andenes en parcelas de comprobación. El diseño experimental utilizado fue bloques completamente randomizado con tres repeticiones en cada localidad. El contenido de proteína incrementa al 50% de floración (21,44%), y disminuye (17,61%) al 100% de floración, incrementando el contenido de fibra en 3,26 % y disminuyendo la calidad del forraje. El uso óptimo de forraje con el tratamiento L9, es del 1 a 50% de inflorescencia visible. La nueva variedad demostró valores superiores a la avena local (Tayko), se puede observar un rendimiento promedio de M.S. en las 9 localidades de 11,39 t ha-1, nivel superior a la variedad local, que en promedio rindió 7,19 t ha-1 y se obtuvo un rendimiento promedio de semilla superior de 3,58 t ha-1. La avena Mellicera es resiliente al cambio climático y puede permitir al productor cosechar semilla en zonas altoandinas por su precocidad (153 días), en comparación que el Tayko.Ítem Phenolic composition, antioxidant and anti-proliferative activities of edible and medicinal plants from the Peruvian Amazon(El Sevier, 2016-06-14) Tauchen, Jan; Bortl, Ludvik; Huml, Lukas; Miksatkova, Petra; Doskocil, Ivo; Marsik, Petr; Panduro Villegas, Pablo Pedro; Bendezu Flores, Ymber; Van Damme, Patrick; Lojka, Bohdan; Havlik, Jaroslav; Lapcik, Oldrich; Kokoska, LadislavAmong 23 extracts of medicinal and edible plants tested, Mauritia flexuosa L.f., Arecaceae, showed significant antioxidant ability (DPPH and ORAC = 1062.9 and 645.9 ± 51.4 μg TE/mg extract, respectively), while Annona montana Macfad., Annonaceae, demonstrated the most promising anti-proliferative effect (IC50 for Hep-G2 and HT-29 = 2.7 and 9.0 μg/ml, respectively). However, combinatory antioxidant/anti-proliferative effect was only detected in Oenocarpus bataua Mart., Arecaceae (DPPH = 903.8 and ORAC = 1024 μg TE/mg extract; IC50 for Hep-G2 and HT-29 at 102.6 and 38.8 μg/ml, respectively) and Inga edulis Mart., Fabaceae (DPPH = 337.0 and ORAC = 795.7 μg TE/mg extract; IC50 for Hep-G2 and HT-29 at 36.3 and 57.9 μg/ml, respectively). Phenolic content was positively correlated with antioxidant potential, however not with anti-proliferative effect. None of these extracts possessed toxicity towards normal foetal lung cells, suggesting their possible use in development of novel plant-based agents with preventive and/or therapeutic action against oxidative stress-related diseases.Ítem The effect of hydrothermal treatment on metabolite composition of hass avocados stored in a controlled atmosphere(MDPI, 2021-11-10) Chirinos, Rosana; Campos, David; Martínez, Sofía; Llanos, Sílfida; Betalleluz Pallardel, Indira; García Ríos, Diego; Pedreschi, RominaAvocado cv. Hass consumption has expanded worldwide given its nutritional, sensory, and functional attributes. In this work, avocado fruit from two harvests was subjected to hydrothermal treatment (38 °C for 1 h) or left untreated (control) and then stored for 30 and 50 days in a controlled atmosphere (4 kPa O2 and 6 kPa CO2 at 7 °C) (HTCA and CA, respectively) with subsequent ripening at ~20 °C. The fruit was evaluated for primary and secondary metabolites at harvest, after storage, and after reaching edible ripeness. A decrease from harvest to edible ripeness in mannoheptulose and perseitol was observed while β-sitosterol, hydrophilic and lipophilic antioxidant activity (H-AOX, L-AOX), abscisic acid, and total phenolics (composed of p-coumaric and caffeic acids such as aglycones or their derivatives) increased. HTCA fruit at edible ripeness displayed higher contents of mannoheptulose, perseitol, β-sitosterol, L-AOX, caffeic acid, and p-coumaric acid derivatives, while CA fruit presented higher contents of α-tocopherol, H-AOX, and syringic acid glycoside for both harvests and storage times. The results indicate that a hydrothermal treatment prior to CA enables fruit of high nutritional value characterized by enhanced content of phenolic compounds at edible ripeness to reach distant markets.Ítem Compost quality optimization through Plackett-Burman’s design(OICC Press, 2024-08-28) Ortiz Dongo, Luis Felipe; Mendez Revollar, Yerly; Solorzano Acosta, Richard; Lastra, Sphyros; Carrion Carrera, GladysPurpose: This research aimed at compost quality optimization through Plackett-Burman’s design application.This statistical method was used to identify and evaluate key factors that impact compost quality and determine its optimal levels. Method: Eight experiments were carried out with variables such as leachate recirculation, Carbon/Nitrogen ratio,manure type, bacterial and fungi incorporation, type of plant material, and compost pile height. Results: Obtained results revealed significant influence of guinea pig manure in compost quality, improving pH and electric conductivity (dS∙m-1) values, as well as its influence on purple corn fresh and dry weight increase. However, the use of guinea pig manure can increase arsenic, mercury, and lead compost levels, but within the range allowed by Peruvian technical standards. Leachate recirculation showed significant effect on compost humidity increase, which decreased its physical quality to not permitted values by Peruvian technical standards. In addition, leachate uses a reduced number of corn leaves, as well as its fresh and dry weight. It was possible to identify optimal conditions to maximize composting process efficiency, through Plackett-Burman’s Design. Conclusion: These findings provide a solid foundation for composting practice's continuous improvement, contributing to high-quality organic fertilizer production more efficiently and sustainably. This study has the potential to guide future research and feasible applications in the agricultural field, favoring more environmentally friendly practices adoption.Ítem Evaluación de la respuesta ovárica en alpacas tratadas con Hormona Folículo Estimulante (FSH)(Sitio Argentino de Producción Animal, 2007-10-31) Cervantes, M.; Huanca Mamani, Teodosio; Palomino, J. M.; Huanca, W.El objetivo del estudio fue evaluar la respuesta ovárica en alpacas tratadas con hormona folículo estimulante (FSH). Se emplearon 10 alpacas huacaya hembras adultas. Todos los animales fueron sometidos al mismo protocolo de superovulación. Se evaluó el número y tamaño de folículos superestimulados y el número y tamaño de cuerpos lúteo. Los resultados obtenidos fueron: 9.2±3.5 folículos superestimulados con diámetro promedio 7.7±1.8mm y 4.1±2.5 cuerpos lúteos con diámetro 8.9±1.9mm. Los resultados muestran una respuesta ovárica moderada, sin embargo es necesario realizar ensayos donde se evalúe así mismo el número de embriones recuperados post monta.Ítem Patterns of Plumericin Concentration in Leaves of Himatanthus tarapotensis (Apocynaceae) and Its Interactions with Herbivory in the Peruvian Amazon(MDPI, 2022-04-08) Amasifuen Guerra, Carlos Alberto; Patel, Kirti; Delprete, Piero G.; Spina, Andréa P.; Grados, Juan; Vásquez Ocmín, Pedro; Gadea, Alice; Rojas, Rosario; Guzmán, Jesús; Sauvain, MichelWe explored the concentration patterns of the bioactive metabolite plumericin produced by Himatanthus tarapotensis (Apocynaceae) under different edaphic conditions and variations in rainfall intensity, as well as its potential role in the chemical defense against insect herbivores. Values of plumericin concentration from leaves were obtained by High-Performance Liquid Chromatography, and evaluated as a function of differences in soil types, variation of precipitation, and variation of the abundance of insect herbivores, using first a Repeated Measures Correlation (rmcorr) and then a Generalized Linear Mixed Model (GLMM) analysis. Plumericin concentration is highly variable among plants, but with a significantly higher concentration in plants growing on clay soil compared to that of the white-sand soil habitat (p < 0.001). Plumericin concentration is not affected by precipitation. The caterpillar of Isognathus leachii (Lepidoptera: Sphingidae) is the most conspicuous herbivore of H. tarapotensis, and its presence is continuous but not related to plumericin concentration, probably because of its capacity to elude the chemical defense of this plant. Nevertheless, our multivariate model revealed that plumericin concentration is related to the abundance of Hymenoptera (Formicidae), and this relationship is significantly influenced by the soil parameters of carbon percentage, clay percentage, and phosphorous percentage (p < 0.001). Plumericin is a mediating agent in the interaction between H. tarapotensis and its natural environment. Variation in plumericin concentration would be induced by the abundance of Hymenoptera (Formicidae), probably as a chemical response against these insects, and by differences in soil nutrient availability.