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Incidencia y sintomatología de cinco virus en parcelas comerciales de chile seco en Aguascalientes, San Luis Potosí y Zacatecas, México
Velásquez-Valle, Rodolfo;Reveles-Torres, Luis Roberto;Mena-Covarrubias, Jaime;
Revista mexicana de ciencias agrícolas , 2012,
Abstract: world-wide the chili pepper crop is affected by more than 60 viral diseases, although very little is known about them in the area of dry pepper plantation in northern-central mexico. consequently, the aims of this work were to identify the presence of the virus and the associated symptoms in commercial dry pepper fields of the states of zacatecas, san luis potosí, and aguascalientes, mexico. mirasol and ancho pepper plants were sampled and the presence of symptoms such as dwarfing, chlorosis, leaf deformation, defoliation, vascular necrosis and joined branches, were recorded. samples were analyzed using das-elisa with the antisera of the tobacco mosaic virus (tobacco mosaic virus: tmv), cucumber mosaic virus (cucumber mosaic virus: cmv), potato virus y (potato virus y: pvy), pepper mottle virus (pepper mottle virus: pepmov), and tobacco etch virus (tobacco etch virus: tev). these viruses were identified in pepper plants collected in dry pepper fields located in the three states mentioned earlier.
El consumidor potencial de durazno (Prunus persica) orgánico en Zacatecas, Aguascalientes y San Luis Potosí
Padilla-Bernal, Luz E.;Pérez-Veyna, Oscar;
Agrociencia , 2008,
Abstract: the world market of organic food is undergoing accelerated growth, and méxico exports most of its production to this market. there are factors that can lower mexico's probabilities of increasing its presence in international markets, and developing the incipient domestic market could be an alternative to reduce dependence on the external market. peach (prunus persica) growers in zacatecas are in the process of converting conventional production to organic, and are willing to sell their produce on the domestic market if they can earn a price premium. this study examines variables that have an influence in local and regional consumers' motivation and willingness to pay a price premium for organic peach. interviews were conducted: 459 in zacatecas, 428 in aguascalientes, and 399 in san luis potosí. the sample size was determined by a simple random method considering the employed population that earned more than five times the minimum wage in the fourth quarter of 2003. the data were processed with a multiple bounded probit model, using maximum likelihood techniques. it was found that the premium consumers are willing to pay is minimum or nil, considering a statistical significance of the estimators of up to 10%.
Relaciones estratigráfico-estructurales en la intersección del sistema de fallas San Luis-Tepehuanes y el graben de Aguascalientes, México central
Loza-Aguirre, Isidro;Nieto-Samaniego, Angel F.;Alaniz-álvarez, Susana A.;Iriondo, Alexander;
Revista mexicana de ciencias geológicas , 2008,
Abstract: the zacatecas-san josé de gracia area, located at southern zacatecas and northern aguascalientes in the borderline between the sierra madre occidental and the mesa central, is particularly important because it is located at the intersection of two regional fault systems: the san luis-tepehuanesfault system and the aguascalientes graben. we mapped the area and measured the faults that affect the cenozoic units in order to know the interaction between these two fault systems during the cenozoic. eight new cenozoic litostratigraphic units were identified, four of which were dated, defining twofelsic volcanic pulses: the first one occurred during middle eocene, with the la bufa ryolite at the base (48.91 ± 0.09 ma) and la virgen formation at the top (36.8 ma; ponce y clark, 1988: economic geology, 83, 1668-1682), the second pulse during the oligocene, comprising rocks with isotopic ages of' 28.0 ± 0.8 ma (garabato ignimbrite) and 27.0 ± 0.7 ma (sierra fría rhyolite), with a magmatic gap between -36 and 29 ma. two deformation events were recognized: the first one (dl) occurred in the paleoceneearly eocene producing wnw and nne normal faults. the second event (d2), of late oligocene-early miocene age, comprised two deformational phases (d2a andd2b) that reactivated preexisting structures and formed new ones. the first phase (d2a) activated nne normal faults and the second phase (d 2b) formed wnw normal faults. an horizontal stretching direction of n60 °e could have generated simultaneous (dl) and alternating (d2) activity in both fault systems, which can be explained if we consider that the observed fault directions are inherited from older basement structures. an apparent left-lateral displacement of the aguascalientes graben is observed at its intersection with the san luis-tepehuanes fault system, but new data herein presented indicate that this apparent structural configuration is inherited from older structures.
El Colegio- Seminario de San Luis Gonzaga de Zacatecas y sus primeras Constituciones  [cached]
José Antonio Gutiérrez G.
Espiral , 2005,
Abstract: This work makes reference to the daily life and discipline at Colegio-Seminario of San Luis Gonzaga of Zacatecas in the second half of the 18th century. In addition to make reference to the beginning of the first period of this cultural center founded and supported thanks to the legacy instituted by doctor Francisco José Pérez de Aragón, its first constitutions, barely commented by those who have studied its history, are stressed. The reader could have a picture of the relations between the performers of this important Jesuit institution, as well as the moral and practical character that covers their daily tasks. This work is the result of a recent research visit to the Indies Archives of Seville, Spain.
Sweet-corn production in the rioverde region, San Luis Potosi, Mexico
Charcas-Salazar,Hilario; Aguirre-Rivera,Juan R; Durán-García,Héctor M;
Agronomía Tropical , 2008,
Abstract: in the state of san luis potosi mexico, a land extent of 29022 hectares to produce maize, zea mays l., under irrigation management are cultivated every year; from these 21 079 hectares (72.6%) are used for grain production, and 7 943 (27.4%) for sweet-corn. 99.7% of the surface used for sweet-corn is located in the rioverde region, in communal plots of 3 hectares in average, where the corn is planted in crop rotation with chili, capsicum annum l., tomato, licopersicum esculentum mill., tree tomato, physalis philadelphica lam., and squash, cucurbita spp. sweet-corn production is obtained with cultivars and traditional culture techniques; however, the productivity and profitability is lower than in other regions of the country. the objective of this work was to analyze the production system of sweet-corn and to know its limitative factors. to collect the information, farmers from the region were interviewed to summarize the cultural practices: the data was sorted and classified through multivariate analysis. the results shown that sweetcorn production system is under a process of transition from traditional to intensive. also we found that the farmers with the best results, normally use low plant density, apply nitrogen fertilizers opportunely and adequately, and sell the harvest before or after the majority of producers.
Pavonia Argentina (Malvaceae) nuevo registro para la flora de la provincia de San Luis (Argentina)
Carosio,María Cecilia; Junqueras,María José; Andersen,Alicia; Fernández Belmonte,María Cecilia;
Multequina , 2010,
Abstract: it has been detected the presence of pavonia argentina in san luis province, argentina.
Selección de genotipos de chile resistentes al complejo patogénico de la marchitez
Anaya-López, José Luis;González-Chavira, Mario Martín;Villordo-Pineda, Emiliano;Rodríguez-Guerra, Raúl;Rodríguez-Martínez, Raúl;Guevara-González, Ramón Gerardo;Guevara-Olvera, Lorenzo;Montero-Tavera, Víctor;Torres-Pacheco, Irineo;
Revista mexicana de ciencias agrícolas , 2011,
Abstract: in mexico the most important root disease of the chili pepper crop is the wilt disease, it is primarily controlled with fumigants and fungicides that help to select resistant isolates and cause environment and health damage. a safe environmental option could be the resistant varieties cultivation, but there are few disease resistance varieties. this study's aim was to isolate the pathogens associated with chili pepper wilt disease in central and north of mexico and to identify chili pepper resistant genotypes. during 2006 and 2007, chili pepper plants with wilt disease symptoms were collected in 118 lots from chihuahua, colima, durango, guanajuato, querétaro, san luis potosí and zacatecas, from which pathogens were isolated and pure cultures were obtained. they were individually or in mixtures inoculated to select resistant germplasm, in 44 chili pepper accessions of inifap's germplasm bank and 141 collections from durango, guanajuato, michoacán, san luis potosí and zacatecas. fusarium spp., was isolated with a 42.6% frequency, rhizoctonia solani 37% and phytophthora capsici 3.9%. 26 collections were identified with at least one of them resistant to fusarium spp., and six to r. solani. only bg102 and bg107 accessions from the gene bank were resistant to p. capsici and to the group of three pathogens. these are potential materials to be used in chili pepper genetic improvement.
Contribución del estado de Zacatecas (México) a la conservación de la riqueza florística del Desierto Chihuahuense
Balleza, José de Jesús;Villase?or, José Luis;
Acta botánica mexicana , 2011,
Abstract: the chihuahuan desert (dch) is the largest and floristically richest arid zone in northern méxico. the dch includes territories of seven mexican states, including zacatecas and san luis potosí where its southern limit is located. zacatecas harbors 46% of the vascular flora recorded in the dch and the asteraceae family is an important component of such richness, both throughout the dch as a whole and within its zacatecan portion. unfortunately, zacatecas has not been adequately considered in the different conservation strategies proposed to protect the floristic richness of the dch. in this paper we describe a selection of sites in zacatecas that are important for the conservation of floristic richness, using 198 species of asteraceae as a surrogate of the entire flora and dividing the fraction of the dch in the state into 26 squares of 30 minutes latitude and longitude. the sites were identifiedby means of an iterative method, the results of which indicate the necessity of protecting 18 squares to ensure the conservation of the totality of species. the location of the most important squares identified, as well as the role that zacatecas may potentially play in the conservation of the biodiversity of the dch are discussed.
Evolución petrológica y geoquímica de un complejo de domos topacíferos en el Campo Volcánico de San Luis Potosí (México)
Rodríguez-Ríos, Rodolfo;Aguillón-Robles, Alfredo;Leroy, Jacques L.;
Revista mexicana de ciencias geológicas , 2007,
Abstract: topaz-bearing rhyolites are widely spread throughout the mesa central of mexico, quite near to the eastern limit of the sierra madre occidental volcanic province (durango, zacatecas and san luis potosí states), whereas in the western part of the usa, they are situated at both sides of the colorado plateau and the rio grande rift. these rhyolites are characterized by fluorine enrichments (f >0.2 wt.%) and by the presence of topaz that have crystallized due to post-magmatic processes. in the san luis potosí volcanic field (slpvf), topaz-bearing rhyolites (san miguelito rhyolite) mainly comprise the el gato (deg) and cerro silva (dcs) domes. these volcanic structures are associated to the extensional tectonics, which developed in the central part of mexico during the mid-tertiary. the san miguelito rhyolite corresponds to a peraluminous, subalkaline, silicic magmatic episode associated to one of the events forming the slpvf. the san miguelito rhyolite contains between 25 and 30% of phenocrysts, this being the quantitative proportion of potassium feldspar ~18.7%, quartz ~7.7%, plagioclase ~2.4%, biotite ~1.2% mineral phases. the slpvf (deg and dcs) topaz-bearing ryholites present high contents of sio2, which vary from ~76.8 to ~79.6 wt.% and an alkalies content of ~6.9 to ~8.5 wt.%, as well as strong potassic character. rhyolitic lava flows also show an enrichment of large ion lithophile elements (lile), a depletion in elements compatible with feldspars (ba, sr, and eu) and a negative anomaly in eu. the slpvf topaz-bearing rhyolites seem to have originated by partial melting of a residual granulitic source from the precambrian continental crust. in accordance with the model proposed, the presence of contemporary mafic magmas throughout the crust produced small volumes of partial crustal melts, including the breakdown of small amounts of fluorine-rich biotite that gave rise to the high fluorine concentration in these rocks. an extensional tectonic environment allowed the
La prolongación austral de las Sierras de San Luis The Southern Prolongation of Sierras de San Luis  [cached]
J. Kostadinoff,D. Gregori,E. Bjerg,A. Raniolo
Revista de la Asociación Geológica Argentina , 2002,
Abstract: Al sur de las Sierras de San Luis se ubican en forma meridiana una serie de altos orográficos cuyo extremo austral son las sierras de Varela, del Pozo Peje y Los Cerrillos. En la sierra de Varela las rocas del basamento están representadas por diversos tipos de esquistos y migmatitas. En el sur de esta sierra se halla un complejo volcánico compuesto por pórfiros riolíticos de edad triásica. Las mediciones del campo gravitatorio y magnético indican la presencia de rocas máficas y ultramáficas en su subsuelo como las halladas en Las águilas y Virorco, en las Sierras de San Luis. En el sector oeste de la cuenca de Alvear se infiere, por los estudios geofísicos, la existencia de rocas básicas. The sierras de Varela, Pozo Peje and Los Cerrillos are the southernmost geomorphological expression of the Sierras de San Luis, a N-S trending mountain range. In the Sierras de Varela, the basement consists of several kinds of schist and migmatites. South of Sierra de Varela, the main outcrops are those of a Triassic rhyolitic volcanic complex. Gravity and magnetic measurements reveal strong anomalies, which are attributed to the presence of mafic and ultramafic rocks in the subsurface. The same type of rocks are responsible for similar geophysical anomalies observed in the area of Las Aguilas and Virorco, in the northern part of the Sierras de San Luis. Geophysical studies suggest that basic rocks are also present in the western part of the Alvear basin.
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