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Search Results: 1 - 10 of 222443 matches for " Efraín;Amador-Ramírez "
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Efecto del riego suplementario en la producción de biomasa y grano de frijol de temporal en Zacatecas, México
Acosta-Díaz, Efraín;Acosta-Gallegos, Jorge Alberto;Amador-Ramírez, Mario Domingo;Padilla-Ramírez, José Saúl;
Agricultura técnica en México , 2009,
Abstract: in the semiarid highlands of north-central mexico, the lack of water for agricultural production is an important problem, particularly since annually a depletion of two m in the water mirror of local wells is taking place and the water storage capacity in dams is limited. because of the above situation, the optimization of water resources through supplemental irrigation in critical stages of bean sown under rainfed conditions is important. the aim of the present research was to determine the effect of supplemental irrigation on shoot biomass accumulation and seed yield in two sets of improved cultivars with different seed type. two experiments were established at cezac experiment station in zacatecas, mexico in 2001; nine black-seeded cultivars were evaluated in one trial, and 14 seed colored cultivars in a second one. all cultivars are of the type iii indeterminate growth habit. two soil moisture levels were utilized: 1) rainfall plus supplemental irrigation and 2) natural rainfall conditions. the rainfall plus supplemental irrigation treatment consisted of maintaining the available soil moisture above 50% throughout the crop-growing season, which was achieved by rainfall plus two irrigations, one at pre- and the second at the flowering stages. the natural rainfall treatment depended only on the rainfall occurred during the growing season. in both experiments, average shoot biomass accumulation and seed yield of the rainfall plus supplemental irrigation were significantly higher (p<0.01) than those in the rainfall treatment. in general, black seeded cultivars, that were significantly later to mature (p<0.05), showed higher shoot dry weight and seed yield in response to the treatment rainfed+supplemental irrigation than the colored cultivars. there was a differential response of the cultivars to the moisture treatments; outstanding black seeded cultivars were negro zacatecas, negro ontiveros and negro z524 from the mesoamerican race, while among seed colored cultiva
Adaptation traits in dry bean cultivars grown under drought stress
Acosta-Díaz, Efraín;Acosta-Gallegos, Jorge Alberto;Trejo-López, Carlos;Padilla-Ramírez, José Saúl;Amador-Ramírez, Mario Domingo;
Agricultura técnica en México , 2009,
Abstract: drought is the major constraint to common bean (phaseolus vulgaris l.) production in mexico. the objective of this study was to identify physiological and phenological traits related to drought adaptation in common bean. a field experiment was conducted under a rainout shelter at the valley of mexico experimental station near texcoco, state of mexico. eight common bean cultivars from different genetic races and growth cycle and contrasted drought response were tested under drought stress and non-stress. irrigation was withheld 55 days after sowing at the initiation of flowering, to induce the stressed treatment. starting at this day, six consecutive nondestructive samplings were conducted at noon every other day. in each sampling, leaf water potential, stomata conductance and co2 assimilation rate were determined. data on phenology were also recorded. at physiological maturity, seed yield and shoot biomass were measured. harvest index was calculated. all cultivars exhibited a tendency to escape drought effects throughout accelerated reproductive development. this response was of small magnitude in mesoamerican cultivars negro cotaxtla 91 and bat 477 (type iii) and significant in cultivars from the durango race such as pinto zapata, bayo madero and bayo criollo del llano. significant difference among cultivars for stomata control was observed with high sensitivity in bat 477 and seq 12, cultivars from the mesoamerican race and in ica palmar from nueva granada race. bred and distinct cultivars ica palmar (type i) and pinto villa (type iii) from durango race, displayed high photosynthetic rate and harvest index, traits or mechanisms directly related to seed yield under stress and non-stress conditions.
Biomasa y rendimiento de frijol tipo flor de junio bajo riego y sequía
Acosta-Díaz, Efraín;Amador-Ramírez, Mario Domingo;Padilla-Ramírez, José Saúl;Gómez-Delgado, J. Patrocinio;Valadez-Montoya, Heladio;
Agricultura técnica en México , 2007,
Abstract: in the state of zacatecas, mexico 200 thousand ha of dry bean flor de junio class are annually sown, and its yield average is 315 kg ha-1. this low yield is due to intermittent drought during the growing season. the objective was to determine the effect of different soil moisture levels on plant maturity, shoot and root dry weight per plant, root-shoot ratio and yield of four bean genotypes. in 2002, two trials were conducted; one under greenhouse conditions and the other in the field at the unidad de agronomía of the universidad autónoma de zacatecas. in the greenhouse four soil moisture levels in 3 kg pots were evaluated; one without drought and three from moderate to severe stress: a) irrigated (r), 100% of the evapotranspired water was restituted every 12 h during the cycle, b) moderate drought (sm), 75% of the volume of r was restituted, c) severe drought (ss), 50% of the volume of r was restituted and d) moderate drought during the vegetative stage and severe drought during the reproductive stage (smv+ssr). in the field, two treatments were tested: rainfed (s), depending on rainfall and rainfed plus supplemental irrigation (s+r), with rainfall, contribution and three irrigations as needed. the stress treatments affected negatively all traits in the genotypes in comparison with r and s+r treatments in greenhouse and field, respectively. in the greenhouse; in comparison to the control (r) the average reductions observed with the smv+ssr treatment were: seven days to mature, 26% in shoot dry weight, 44% in root dry weight and 53% in yield. the negative effects increased accordingly to the drought level applied, except for root-shoot ratio, which increased with the stress. under field conditions, the average reductions under the rainfed treatment (s) as compared to (s+r) were: 13 days for maturity, 34% in shoot dry weight and 48% in yield. on the basis of yield reduction, drought susceptibility index and geometric mean of yield, lines uaz fj 2 and uaz fj 3 resulte
Efecto de la sequía en la producción de biomasa y grano de frijol
Acosta-Díaz, Efraín;Hernández-Torres, Ismael;Rodríguez-Guerra, Raúl;Pedroza-Flores, Jesús;Amador-Ramírez, Mario D.;Padilla-Ramírez, José Saúl;
Revista mexicana de ciencias agrícolas , 2011,
Abstract: intermittent drought is most limiting factor for bean production (phaseolus vulgaris l.) under seasonal conditions in mexico. aim of this work was to determine drought effect on biomass accumulation of sprout and grain yield in creole and introduced seasonal bean varieties. two experiments were set, one with 21 native varieties and another with 15 introduced varieties, from different uncertain type growth habit, at academic unit la asención from agronomy school of universidad autónoma de nuevo león, mexico in 2009. experiments were done under two treatments of soil humidity: irrigation during whole cycle and drought. in irrigation treatment soil was kept above 60% of serviceable humidity during cultivation cycle, by precipitation and four irrigation aids (two before and other two after flowering), while in treatment of drought irrigation was suspended when flowering started. in both experiments, under drought condition biomass accumulation of sprout and grain yield was significantly lower (p≤ 0.01) than in irrigation treatment. in general, effect of drought treatment on sprout's dry weight was greater in native varieties, while effect on grain yield was greater in introduced varieties. in drought, varieties with higher yield were: native, pinto-2, pinto-1, amarillo mantequilla, boleado, bayo blanco, canelo and quipincillo rojo-1; and introduced, peruano, flor de mayo media oreja, pinto-5 and ojo de cabra. in accordance with drought susceptibility index and geometric average, most efficient varieties for production of grain yield under both humidity conditions were: pinto-2, amarillo mantequilla, pinto-1, boleado, peruano, flor de mayo media oreja, pinto-5 and ojo de cabra; without exception, all these varieties were collected in test region, which demonstrates importance of local adaptation under drought conditions.
Presencia de Circulifer tenellus Baker y Beet mild curly top virus en maleza durante el invierno en el centro norte de México Circulifer tenellus Baker and Beet mild curly top virus presence in weeds during the winter in north-central Mexico
Rodolfo Velásquez-Valle,Luis Roberto Reveles-Torres,Mario Domingo Amador-Ramírez,María Mercedes Medina-Aguilar
Revista mexicana de ciencias agrícolas , 2012,
Abstract: Una de las enfermedades más importantes del chile para secado en el norte centro de México es la denominada amarillamientos del chile. Existe poca información acerca de la interacción entre el vector (Circulifer tenellus Baker), el Beet mild curly top virus y la maleza durante el invierno en esta región, consecuentemente el objetivo del trabajo fue identificar maleza de invierno que sirve como refugio para el vector y hospedero del virus en esta región. Entre enero y marzo de 2011 se muestrearon 26 manchones de maleza en los estados de Aguascalientes y Zacatecas. Se capturaron adultos de C. tenellus en 69.2% de los manchones de maleza muestreados; la mayoría (75.5%) de los especímenes eran hembras. El Beet mild curly top fue identificado sólo 15.4% de los sitios de muestreo infectando especies de maleza como Eruca sativa, Reseda sp., Chenopodium sp. y Solanum rostratum L. One of the most important diseases of chili pepper for drying in the north-central Mexico is called yellowing of chili. There is little information about the interaction between the vector (Circulifer tenellus Baker), the Beet mild curly top virus and weeds during the winter in this region; therefore, the objective was to identify winter weeds that serve as are fuge for the vector and host of the virus in this region. Between January and March, 2011, 26 patches of weed were sampled in Aguascalientes and Zacatecas. Adult C. tenellus were captured in 69.2% of the weed sampled patches; most of the specimens were females (75.5%). Beet mild curly top was identified in only 15.4% of the sampling sites, infecting weed species suchas Eruca sativa, Reseda sp., Chenopodium sp. and Solanum rostratum L.
Relación entre índice de área foliar y rendimiento en frijol bajo condiciones de secano
Acosta Díaz, Efraín;Acosta Gallegos, Jorge Alberto;Amador Ramírez, Mario Domingo;Padilla Ramírez, José Saúl;
Agricultura técnica en México , 2008,
Abstract: the leaves of the bean plant are one of the organs more affected by intermittent drought stress. the objective of this research was to determine the relationship between the leaf area index and seed yield at four phenological stages in dry bean cultivars of different grain type grown under rainfed conditions. the study was conducted in the main three producing areas in the state of zacatecas, mexico, during the summer of 2002 at six locations: four in the northwestern area, sown with a cv. negro san luis type; one in the central region, with a cv. of the flor de junio type and one in the southeastern region, with a cv. of the flor de mayo type. in each location, eight fields were chosen and in each two rows of 5 m longitude with four replications. four leaf area index samplings were made at four phenological stages: at the beginning of flowering, beginning of pod formation, beginning seed filling, and intermediate seed filling. seed yield was determined at physiological maturity. the relationship between the leaf area index at different stages and seed yield was determined by simple correlations. in general, average leaf area index increased with the development of the phenological stages, the highest values were observed at the beginning of the seed filling stage. average seed yield varied among locations: 130 g m-2 at the northwestern region with cv. negro san luis type, 139 g m-2 at central with cv. flor de junio type and 95 g m-2 at southwestern with cv. flor de mayo type.
Organización de las interneuronas positivas para parvoalbúmina de la corteza frontopolar en el ser humano: implicaciones para el procesamiento cognitivo y emocional
Efraín Buriticá Ramírez,Hernán J. Pimienta J.
Iatreia , 2005,
Abstract: La Región frontopolar de la corteza cerebral humana se vincula con el procesamiento explícito y la valoración de los estados mentales internos y externos, la recuperación de la información episódica, la memoria prospectiva y la disociación y reasignación de la atención. Los mecanismos inhibitorios de las interneuronas que expresan Parvoalbúmina son fundamentales para las anteriores funciones.
Choque cardiogénico: El tratamiento en el futuro cercano
Gaxiola, Efraín;Ramírez-Sánchez, Ulises;
Archivos de cardiología de México , 2006,
Abstract: the mortality rate for cardiogenic shock has decreased over the past decade. these improvements are presumed to reflect increased use of intraaortic ballon counterpulsation and coronary reperfusion strategies which, by restoring patency to the infarct-related artery, can limit infarct size. despite these therapeutic measures, mortality rates remain elevated. current strategies are aimed at decreasing reperfusion times and measures to preserve and prolong myocardial cell viability.
A Synopsis of Pterostemon (Iteaceae), a Group Endemic to Mexico  [PDF]
Judith Márquez Guzmán, Martha Martínez Gordillo, Ramiro Cruz Durán, Jaime Jiménez Ramírez, María Cristina Pérez-Amador
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.412A1001
Abstract: The genus Pterostemon Schauer (Iteaceae), is a group of three species restricted in distribution to Mexico. It includes: Pterostemon mexicanus Schauer, P. rotundifolius Ramírez, and P. bravoanus J. Jiménez-Ram. & Martínez Gordillo. On the basis of field observations and herbarium specimens, we review the morphology (vegetative and reproductive), and distribution to give an updated taxonomic treatment for the genus. Additionally the utility of morphological characters is evaluated for taxomic use, and detailed taxonomic descriptions and ecological associations are given for each species.
Corteza frontopolar humana: área 10
Efraín Buriticá-Ramírez,Hernán José Pimienta-Jiménez
Revista Latinoamericana de Psicología , 2007,
Abstract: La corteza frontopolar, y en particular, el área 10, está vinculada con procesos cognitivos muy complejos como la planeación, la introspección, la memoria retrospectiva y prospectiva, la disociación de la atención y resolución de problemas que implican tareas simultáneas. Esta información se ha derivado de estudios con neuroimagenología funcional. A pesar de lo anterior, su organización celular, neuroquímica y patrón de conexiones han sido poco reconocidos. En el presente trabajo se pretende una descripción anatomo-funcional del área 10, cubriendo aspectos anatómicos, citoarquitectónicos, quimioarquitectónicos y de conectividad. Se incluyen algunas observaciones de nuestro grupo en tejido humano postmortem. La información considerada es útil para establecer una aproximación estructural y funcional de esta área en el contexto de la organización del lóbulo frontal del humano.
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