Provance M.C.,University of California at Riverside |
Garcia-Ruiz I.,Centro Interdisciplinario Of Investigacion Para El Desarrollo Integral Regional Ciidir |
Thommes C.,University of California at Davis |
Ross-Ibarra J.,University of California at Davis
Genetic Resources and Crop Evolution | Year: 2013
The traditional cultivation of an endangered species, Diospyros riojae, in North-Central Mexico, and the sale of its fruit, is described for the first time. This is complemented by the first examination of genetic structure in New World Ebenaceae. Genetic comparisons are made among 27 accessions of D. riojae from across its known range of cultivation, and individuals of Diospyros conzattii, Diospyros digyna, Diospyros californica, Diospyros rosei, Diospyros rekoi and an unknown species of Diospyros from Oaxaca, Mexico. Morphological comparisons are made between D. conzattii, D. riojae, and the unknown species of Diospyros from Oaxaca. D. riojae is cultivated in two markedly different climates: arid and semi-arid localities west of the Sierra Gorda, especially near Tecozautla, Hidalgo, and humid areas of the Huasteca Region, east of the Sierra Gorda. Much lower levels of genetic diversity were detected in western populations, where populations are larger, and management intensity is the greatest. Neither the results of our genetic analysis, nor our morphological analysis of recent collections of D. riojae, D. conzattii, and an unknown species from Oaxaca, are consistent with the most recent revision of Neotropical Diospyros. Taxon-level divergence, rather than cultivar-level divergence, is suggested for D. riojae and D. conzattii. © 2013 Springer Science+Business Media Dordrecht.
Escobedo-Bonilla C.M.,Centro Interdisciplinario Of Investigacion Para El Desarrollo Integral Regional Ciidir
Journal of Antivirals and Antiretrovirals | Year: 2013
Shrimp culture has long been done in Asia and America to provide high quality food to people. Modern aquaculture uses advanced techniques to increase shrimp production but it also has enhanced the occurrence of infectious diseases. Disease is the main pitfall for the development and sustainability of shrimp aquaculture worldwide. In the last decade several methods and strategies have been developed and evaluated under experimental conditions in order to curb the negative impact of viral infections. Among these, RNA interference is the most recent tool against viral diseases in shrimp and it is deemed as a promising biotechnology to boost shrimp production. This paper gives a broad overview of the RNAi methods used to fight viral diseases in shrimp aquaculture compared to the antiviral effect of methods previously evaluated against viruses. It also gives examples of the use of RNAi to learn more on mechanisms of the shrimp defense response. The application of RNAi to fight or treat viral infections in shrimp aquaculture has yet to come and it depends on the efficacy of RNAi against several viral diseases, evaluation of environment and food safety and the development of cheap, massive delivery methods of RNAi molecules to shrimp farming facilities. © 2011 Escobedo-Bonilla CM.
Leal J.A.R.,San Luis Potosí Institute of Scientific Research and Technology |
Medrano C.N.,San Luis Potosí Institute of Scientific Research and Technology |
Silva F.O.T.,Research Center En Geografia omatica Ing Jorge mayo Ac |
Garcia J.T.S.,Centro Interdisciplinario Of Investigacion Para El Desarrollo Integral Regional Ciidir |
Gutierrez L.R.R.,San Luis Potosí Institute of Scientific Research and Technology
Hydrogeology Journal | Year: 2012
Aquifer systems present intrinsic properties such as vulnerability, which is identified as the potential risk of groundwater pollution by contaminants generated by human activity. When there are surface sources of pollution, usually there is a direct relationship between high vulnerability and decreased water quality. Nevertheless, this relationship is not observed in all aquifers and so the causative circumstances of inconsistencies between aquifer vulnerability and water quality have been investigated. This work addresses the vulnerability assessment of the Chapala Marsh area, Mexico, using SINTACS analysis. The Chapala Marsh aquifer is characterized by a granular structure and a fractured recharge zone; there are natural and anthropogenic sources of pollution. The results show discrepancies between the vulnerability indices and groundwater quality, as indicated by the existence of vulnerable areas with good water quality and vice versa. This is because the SINTACS method works well when contaminants have only vertical movement. For scenarios with lateral movement of contaminants, the method of geographic weighted regression (GWR) is used to model the influence of potential sources of contaminants on the water quality. © 2012 Springer-Verlag.
Relationship between chloride concentration and electrical conductivity in groundwater and its estimation from vertical electrical soundings (VESs) in Guasave, Sinaloa, Mexico [Relación entre concentración de cloruros y conductividad eléctrica en aguas subterráneas y su estimación a partir de Sondeos Eléctricos Verticales (SEV) en Guasave, Sinaloa, México]
Peinado-Guevara H.,National Autonomous University of Mexico |
Peinado-Guevara H.,Autonomous University of Sinaloa |
Green-Ruiz C.,National Autonomous University of Mexico |
Herrera-Barrientos J.,CICESE |
And 4 more authors.
Ciencia e Investigacion Agraria | Year: 2012
Soils in arid or semi-arid areas often have salinity problems, so the quality of irrigation water plays an important role in agricultural production. Groundwater quality analysis includes the determination of chloride ions, which are toxic to plants in high concentrations. A total of 1358 groundwater samples were collected and analyzed in the period 1980-2008. Water electrical conductivity [EC] and chloride ion concentration values were related by the linear equation [Cl-] = 4.928 EC (R> 0.94), to estimate the concentration of chloride ions as a function of the electrical conductivity of water in the study area. A geophysical survey was conducted through 34 Vertical Electrical Soundings (VESs) to calculate the water electrical conductivity from the interpretation of the apparent resistivity data. Twenty-nine VESs were used to relate the resistivity of the saturated formation (Ro) with that for the groundwater (Rw) by the linear equation Rw = 0.427 Ro + 1.987. Then, EC was estimated as the inverse of Rw. Finally, the chloride ion concentration was determined by the equation mentioned above. Following the same procedure for the five remaining VESs, which were acquired in places where there are no wells, the chloride ion concentration and the electrical resistivity of the saturated formation (Ro) and groundwater (Rw and its inverse EC) were obtained without requiring a destructive technique.
Mondragon Chaparro D.,Centro Interdisciplinario Of Investigacion Para El Desarrollo Integral Regional Ciidir |
Ticktin T.,University of Hawaii at Manoa
Conservation Biology | Year: 2011
Hundreds of epiphytic bromeliads species are harvested from the wild for trade and for cultural uses, but little is known about the effects of this harvest. We assessed the potential demographic effects of harvesting from the wild on 2 epiphytic bromeliads: Tillandsia macdougallii, an atmospheric bromeliad (adsorbs water and nutrients directly from the atmosphere), and T. violaceae, a tank bromeliad (accumulates water and organic material between its leaves). We also examined an alternative to harvesting bromeliads from trees-the collection of fallen bromeliads from the forest floor. We censused populations of T. macdougallii each year from 2005 to 2010 and of T. violaceae from 2005 to 2008, in Oaxaca, Mexico. We also measured monthly fall rates of bromeliads over 1 year and monitored the survival of fallen bromeliads on the forest floor. The tank bromeliad had significantly higher rates of survival, reproduction, and stochastic population growth rates (λs) than the atmospheric bromeliad, but λs for both species were <1, which suggests that the populations will decline even without harvest. Elasticity patterns differed between species, but in both, survival of large individuals had high elasticity values. No fallen bromeliads survived more than 1.5 years on the forest floor and the rate of bromeliad fall was comparable to current harvest rates. Low rates of population growth recorded for the species we studied and other epiphytic bromeliads and high elasticity values for the vital rates that were most affected by harvest suggest that commercial harvesting in the wild of these species is not sustainable. We propose the collection of fallen bromeliads as an ecologically and, potentially, economically viable alternative. ©2011 Society for Conservation Biology.