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Search Results: 1 - 10 of 138560 matches for " Víctor Arturo;Ayala Garay "
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Calidad fisiológica de semillas de Physalis ixocarpa en función de madurez a cosecha y condiciones de almacenamiento Physalis ixocarpa physiological seed quality in terms of maturity at harvest and storage conditions
Ignacio Pérez Camacho,Víctor Arturo González Hernández,óscar Javier Ayala Garay,José Alfredo Carrillo Salazar
Revista mexicana de ciencias agrícolas , 2012,
Abstract: El deterioro de la semilla durante el almacenamiento reduce su capacidad germinativa y el establecimiento de plántulas en campo. En semillas de Physalis ixocarpa Brot., se desconocen los niveles de los factores ambientales que afectan su longevidad germinativa y su desempe o fisiológico durante el almacenamiento, en función del estado de desarrollo a la cosecha. En esta investigación se evaluó semilla de la variedad Chapingo cosechada en tres estados de desarrollo (45, 55 y 65 días después de la polinización), en tres periodos de almacenamiento (0, 4 y 8 meses) combinados con cinco ambientes que incluyeron dos temperaturas (23.8 y 5.3 °C) y dos niveles de humedad relativa (24 y 81%). Se encontró que la semilla puede mantener su capacidad germinativa inicial (70%), por al menos durante 8 meses cuando se almacena en baja humedad relativa (24%) o en frío (5 °C), ya que la combinación de alta humedad relativa (81%) y temperatura de 23 °C causan el deterioro de la semilla. El deterioro se manifiesta en reducciones de germinación de 70 a 29%, viabilidad de 81 a 46%, velocidad de emergencia de radícula de 20.4 a 9.9 radículas por día, velocidad de emergencia de la parte aérea de 6.3 a 2.3 plántulas por día, respiración de 16.1 a6.6nmol CO2 g-1 s-1 y en un aumento en conductividad eléctrica de 32 a 97 μS cm-1 g-1. Las semillas de 55 días de edad ya han alcanzado la madurez fisiológica, pues germinan igual y con el mismo vigor que las semillas de 65 días. Las semillas inmaduras de 45 días ya poseen capacidad de germinar, aunque 10% menos que la semilla madura y con menor vigor. Seed deterioration during storage reduces germination and seedling establishment in the field. For Physalis ixocarpa Brot. seeds the levels of environmental factors that affect its germination longevity and physiological performance during storage, depending on the state of development at harvest are unknown. For this research, variety Chapingo seeds harvested at three stages of development were evaluated (45, 55 and 65 days after pollination), in three storage periods (0, 4 and 8 months) combined with five environments including two temperatures (23.8 and 5.3 °C) and two relative humidity levels (24 and 81 %). It was found that, the seeds can maintain its initial germination capacity (70%) for at least 8 months when stored under low relative humidity (24%) or cold (5 °C), since the combination of high relative humidity (81%) and temperature of 23 °C cause degradation in the seeds. The deterioration is manifested in reduced germination from 70 to 29%, viability from 81 to 46%, radicle rat
Calidad fisiológica de semillas de Physalis ixocarpa en función de madurez a cosecha y condiciones de almacenamiento
Pérez Camacho, Ignacio;González Hernández, Víctor Arturo;Ayala Garay, óscar Javier;Carrillo Salazar, José Alfredo;Santos, Gabino García de los;Pe?a Lomelí, Aureliano;Cruz Crespo, Elia;
Revista mexicana de ciencias agrícolas , 2012,
Abstract: seed deterioration during storage reduces germination and seedling establishment in the field. for physalis ixocarpa brot. seeds the levels of environmental factors that affect its germination longevity and physiological performance during storage, depending on the state of development at harvest are unknown. for this research, variety chapingo seeds harvested at three stages of development were evaluated (45, 55 and 65 days after pollination), in three storage periods (0, 4 and 8 months) combined with five environments including two temperatures (23.8 and 5.3 °c) and two relative humidity levels (24 and 81 %). it was found that, the seeds can maintain its initial germination capacity (70%) for at least 8 months when stored under low relative humidity (24%) or cold (5 °c), since the combination of high relative humidity (81%) and temperature of 23 °c cause degradation in the seeds. the deterioration is manifested in reduced germination from 70 to 29%, viability from 81 to 46%, radicle rate of emergence from 20.4 to 9.9 radicles per day, rate of emergence of the aerial part from 6.3 to 2.3 seedlings per day, respiration from 16.1 to 6.6 nmol co2 g-1 s-1 and an increase in electrical conductivity from 32 to 97 μs cm-1 g-1. seeds of 55 days of age have already reached physiological maturity, since they germinate with the same vigor that the seeds of 65 days. immature seeds of 45 days do have ability to germinate, although 10% less than mature seed and with less vigor.
Efecto de desarrollo y secado de semillas de physalis ixocarpa brot en germinación, vigor y contenido de azúcares
Pérez Camacho,Ignacio; González Hernández,Víctor A; Molina Moreno,Juan C; Ayala Garay,óscar J; Pe?a Lomelí,Aureliano;
Interciencia , 2008,
Abstract: during seed development the humidity content decreases while germinability increases, a process known as acquisition of tolerance to desiccation. however, this process is not well known in seeds of physalis ixocarpa. the effect of three drying methods in the physiological quality (germination and vigor) and sugar content of seeds of p. ixocarpa cv chapingo was evaluated at different development stages. seeds were extracted at six fruit development stages (28, 35, 42, 49, 56 and 63 days after flowering, ddf) and exposed to three types of drying: forced air at 25oc or at room temperature, and a control consisting in planting the seeds inmediately. in all development stages, both drying treatments elevated germination up to 42% (p £ 0.05) over the control. the emergency rate (seed vigor) increased on average from 7 seedlings per day at 28 ddf to 18 seedlings per day at 42 ddf, independent of the drying method, which means that these drying methods affected germinability instead of seed vigor. in all the treatments, saccharose and rafinose contents increased during seed development, whereas monosaccharides contents (glucose, fructuose and sorbitol) were not related to the drying treatments.
Desarrollo de fruto y semilla de cinco variedades de tomate de cáscara en Sinaloa
Rodríguez-Burgos, Alejo;Ayala-Garay, Oscar Javier;Hernández Livera, Adrián;Leal-León, Víctor Manuel;Cortez-Mondaca, Edgardo;
Revista mexicana de ciencias agrícolas , 2011,
Abstract: husk tomato has been cultivated in sinaloa, mexico, for 20 years and its importance increased in the last decade. there is little systematic information of management and productive potential of different varieties. the development of fruits and seeds and its quality, was studied on five varieties (querétaro, rendidora, mahone, orizaba, carrice?o) planted on two dates (pd1: september 6th and pd2: october 16th, 2008). querétaro and mahone varieties had on average, the longest fruit (37 and 34 cm), wider (43 and 40 cm) and heavier (38 and 34 g) respectively, this led the querétaro variety to a higher (53 t ha-1) fruit yield (fruty). the best crop development was observed in pd1, because pd2 presented a severe attack of powdery mildew (podosphaera xanhtii), obtaining a fruty 7.5 times lower. the growth kinetics of fruit's weight was sigmoidal and showed that the peak was reached at 35 days after flowering (af) (38 g). there were differences in the growth kinetics of a thousand seeds weight between the two pd; while in pd1, growth was linear, meaning that the maximum was not reached at 56 af (last sampling); in pd2, growth reached a maximum at 42 af (1.26 g). similarly, the germination and seed vigor (first count in germination test) peaked at 56 af (82% and 71% respectively).
Adaptacion de un modelo de deterioro a semillas de tomate de cáscara
Carrillo Salazar, J. Alfredo;Pichardo González, J. Manuel;Ayala Garay, óscar J.;González Hernández, Víctor A.;Pe?a Lomelí, Aureliano;
Revista fitotecnia mexicana , 2011,
Abstract: air temperature and relative humidity are the most important environmental factors affecting the viability of stored seeds. in this investigation, the viability of husk tomato (physalis ixocarpa brot.) seeds stored without control of air temperature and relative humidity, was estimated with a model designed for tomato seeds (lycopersicon esculentum mill.). the seed moisture was calculated using the air temperature and relative humidity of storage conditions, while the seed viability was calculated using the ellis and roberts equation. the coefficient lambda (λ) in the seed water content equation, and the values of ch, cw, cq, and ki in the ellis and roberts equation were calibrated with the marquardt and simplex optimization methods. the mean error of the difference between observed and modeled data (mbe), the mean error in percent (mpe), and the root square of the mean difference between modeled and observed data (rmsd), were used as bias measurements. the calibrated lambda (61.6) for husk tomato seeds was 62 % higher than that for tomato, but this calibrated value rendered an adequate average (5 %) of the seed moisture. ch, cw, and ki optimized simultaneously with the simplex method produced the best calibration of the ellis and roberts equation, since each parameter changed less than 4.6 % from its original value, with a mean error of 3.4 % and a r2 over 0.97. modeled viability of husk tomato seeds was higher or equal than 85 % after 263 d of storage, and there after 50 % of viability was lost in 4 years and 5 months.
Desarrollo de fruto y semilla de cinco variedades de tomate de cáscara en Sinaloa Fruit and seed development of five varieties of husk tomato in Sinaloa
Alejo Rodríguez-Burgos,Oscar Javier Ayala-Garay,Adrián Hernández Livera,Víctor Manuel Leal-León
Revista mexicana de ciencias agrícolas , 2011,
Abstract: El tomate de cáscara se explota en Sinaloa, México, desde hace 20 a os y su importancia se incrementó en la última década. Existe muy poca información sistematizada del manejo y potencial productivo de diferentes variedades. Se estudió el desarrollo de fruto y semilla, y la calidad de esta, en cinco variedades (Querétaro, Rendidora, Mahone, Orizaba, Carrice o) sembradas en dos fechas (FS1: 6 de septiembre y FS2: 16 de octubre de 2008). Las variedades Querétaro y Mahone tuvieron en promedio un fruto más largo (37 y 34 cm), ancho (43 y 40 cm) y pesado (38 y 34 g) respectivamente, esto llevó a la variedad Querétaro un rendimiento de fruto (RendF) más alto (53 t ha-1). El mejor desarrollo de cultivo se observó en FS1, debido que en FS2 se presentó un fuerte ataque de cenicilla (Podosphaera xanhtii), obteniéndose un RendF 7.5 veces menor. La cinética de crecimiento del peso de fruto fue sigmoidal y mostró que el máximo se alcanzó a los 35 días después de la floración (DF) (38 g). Existieron diferencias en la cinética del crecimiento del peso de mil semillas entre ambas FS, mientras que en FS1 el crecimiento fue lineal, significa que el máximo no se alcanzó a 56 DF (último muestreo), en FS2 el crecimiento llegó a un máximo a los 42 DF (1.26 g). Igualmente la germinación y vigor de la semilla (primer conteo en la prueba de germinación) alcanzaron el máximo a los 56 DF (82% y 71%, respectivamente). Husk tomato has been cultivated in Sinaloa, Mexico, for 20 years and its importance increased in the last decade. There is little systematic information of management and productive potential of different varieties. The development of fruits and seeds and its quality, was studied on five varieties (Querétaro, Rendidora, Mahone, Orizaba, Carrice o) planted on two dates (PD1: September 6th and PD2: October 16th, 2008). Querétaro and Mahone varieties had on average, the longest fruit (37 and 34 cm), wider (43 and 40 cm) and heavier (38 and 34 g) respectively, this led the Querétaro variety to a higher (53 t ha-1) fruit yield (FrutY). The best crop development was observed in PD1, because PD2 presented a severe attack of powdery mildew (Podosphaera xanhtii), obtaining a FrutY 7.5 times lower. The growth kinetics of fruit's weight was sigmoidal and showed that the peak was reached at 35 days after flowering (AF) (38 g). There were differences in the growth kinetics of a thousand seeds weight between the two PD; while in PD1, growth was linear, meaning that the maximum was not reached at 56 AF (last sampling); in PD2, growth reached a maximum at 42 AF (1.26 g). Similarly,
Calidad fisiológica, ácidos grasos y respiración en semillas de tomate de cáscara deterioradas artificialmente
Pichardo González, Juan M.;Ayala Garay, óscar J.;González Hernández, Víctor A.;Flores Ortiz, César M.;Carrillo Salazar, Alfredo;Pe?a Lomelí, Aureliano;Robledo Paz, Alejandrina;García de los Santos, Gabino;
Revista fitotecnia mexicana , 2010,
Abstract: during storage, seeds deteriorate due to mechanisms that reduce their germination rate, seedling growth rate and tolerance to adverse conditions. seed deterioration can be measured by means of artificial aging tests (aa). in this research the artificial deterioration of husk tomato seeds (physalis ixocarpa brot.) var. 'chf1-chapingo' was evaluated, and the germination rate was correlated with fatty acids content and respiratory activity. in a first experiment, seeds were artificially aged by applying 55, 65 and 75 % of relative humidity (rh) at 45 and 50 °c, for 30 d and germination rate (g, %), seed vigor (radical emergence rate, rer) and fatty acids content (quantified by means of a gas chromatograph connected to a mass spectrometer) were evaluated. in a second experiment, seeds were aged by imposing 50, 55, 60, 65, 70, 75 and 80 % of rh at 50 °c for 30 d; g, rer and respiration rate (measured after 72 h of imbibition) were measured as response variables. it was found that linoleic acid was the most abundant fatty acid (87-93 % of the total content) in these seeds, and the increase of heat and relative humidity caused a significant reduction (p ≤ 0.05) in g and ser without affecting fatty acids content. compared to untreated seeds (control), the combined effect of 50 °c and 65 % rh produced losses of 53 % in g and of 92 % in rer, in experiment 1. the same treatment (50 °c and 65 % rh) induced losses of 21 % in g and of 78 % in rer when compared to responses at 50 °c and 50 % rh. the respiratory rate correlated with the losses in g (r = 0.88) and rer (r = 0.99), thus indicating that loss of physiological quality in deteriorated seeds can be attributed to the reduction in respiratory activity.
Rese a de " Reinvención de la exclusión social en tiempos de crisis" de Joaquín García Roca.
Víctor Renes Ayala
Polis : Revista de la Universidad Bolivariana , 2012,
Abstract:
Null controllability on Lie groups
Víctor Ayala,Eyüp Kizil
Proyecciones (Antofagasta) , 2013,
Abstract: We prove an extension of a classical result for null controllability of linear control systems on Euclidean spaces, to linear control systems on a connected Lie group G, assumed to be simply connected and nilpotent.
Market orientation at universities: Construct and exploratory validation
Rivera-Camino,Jaime; Molero Ayala,Víctor;
Innovar , 2010,
Abstract: faced with a panorama of growing competitiveness in which universities are forced to get resources on their own, the concept of market orientation can be seen as a solution backed by ample literature. however, the existing literature is based principally on the profit-making sector with the publications in the educational field being still scarce. the purpose of our exploratory research is to develop and validate a market orientation measure in a sampling of spanish universities. the scale integrates and expands the theoretical proposals from previous research; it shows acceptable levels of reliability and validity while allowing the setting-up of future lines of research in the area.
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