Rodriguez-Leyva E.,Colegio de Mexico |
Lomeli-Flores J.R.,Colegio de Mexico |
Valdez-Carrasco J.M.,Colegio de Mexico |
Jones R.W.,University Autnoma Of Quertaro |
Stansly P.A.,University of Florida
Southwestern Entomologist | Year: 2012
The pepper weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae), is a key pest of cultivated peppers (Cepsicum spp.) in the southern United States, Mexico, Central America, and on some islands of the Caribbean. Control of the pest is difficult and dependant on insecticide, with no effective biological control program yet developed. New species and records of parasitoids collected from various localities within the probable regions of origin of the pepper weevil in Mexico are listed. In total, 102 parasitoid specimens of six genera were collected. Of these, Eupelmus cushmeni (Crawford) and Beryscepus hunteri (Crawford) were recorded for the first time as primary parasitoids of the pepper weevil. A key to identify the genera of hymenopteran parasitoids attacking pepper weevil is also presented.
Kuester A.P.,Iowa State University |
Jones R.W.,University Autnoma Of Quertaro |
Sappington T.W.,Iowa State University |
Kim K.S.,Seoul National University |
And 4 more authors.
Annals of the Entomological Society of America | Year: 2012
Although the boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a devastating pest in the United States and Mexico, its population structure and genetic diversity in Mexico on wild and cultivated cotton hosts (genus Gossypium) is poorly understood. Past studies using morphology, host use, and distribution records suggest that A. grandis grandis comprises three forms with host-associated characteristics: the southeastern form (from domesticated Gossypium hirsutum L., southeastern United States and northeastern Mexico), the thurberia form (from Gossypium thurberi Todaro, Arizona and northwestern Mexico), and the Mexican form (from multiple Gossypium species and other malvaceous plant genera in the remainder of Mexico and Central America). However, the phylogenetic relationships, host preferences, and distributions of these forms are not completely understood. An alternative hypothesis of an eastern and western form of the boll weevil is suggested by the suspected phylogeographic range expansion from an ancestral distribution in the tropics northward along both Mexican coasts, culminating in the maximally contrasting phenotypes observed in the northeastern and northwestern arms of the current distribution. In this study, we sequenced one mitochondrial and four nuclear genes to gain insight into the evolutionary relationships among the putative forms and their distributions on wild and domesticated cotton hosts. Using models of evolution, we compared the three-form to the two-form classification and to two alternative classifications that incorporate geography and host use traits. The genetic data at most loci provide stronger support for the two-form than the three-form hypothesis, with an eastern and western group separated by the Sierra Madre Occidental mountain range. They do not support separate taxonomic status for boll weevils developing on G. thurberi. © 2012 Entomological Society of America. © 2012 Entomological Society of America.
Brcenas R.T.,University Autnoma Of Quertaro |
Hawkins J.A.,University of Reading |
Chiang F.,National Autonomous University of Mexico
Haseltonia | Year: 2012
The names Opuntia bulbispina, O. clavata, O. emoryi and O. grahamii, originally proposed by George Engelmann between 1848 and 1856, are reviewed and typified after new findings of previously unknown voucher specimens. Original materials collected by some of the collaborators employed by Engelmann during the Mexican Boundary Survey were discovered in a loan from the Torrey Herbarium at the New York Botanical Garden (NY). Many of the materials include fragments of stems and fruits, and others include only sectioned flowers and some seeds. Particularly good descriptions of the species here concerned were published in Engelmann's "Synopsis of the Cactaceae" in 1857, and exceptional illustrations were produced by Paulus Roetter and printed in "Cactaceae of the Boundary" in 1859. The problems surrounding some previous typifications of these names range from typification of joint lectotypes to illegitimate typifications of illustrations when original material was known to exist. The materials selected for typification were collected by the Mexican Boundary Survey and are lodged at the herbaria of the Missouri Botanical Garden (MO) and the New York Botanical Garden (NY); some are illustrations published by Engelmann.
Rojas E.,University Autnoma Of Quertaro |
Horta J.,University Autnoma Of Quertaro |
Lopez-Lara T.,University Autnoma Of Quertaro |
Hernandez J.B.,University Autnoma Of Quertaro
Probabilistic Engineering Mechanics | Year: 2011
A probabilistic solid-porous model has been developed to determine the shear strength of unsaturated soils. The probabilistic model was built by analyzing the probability of a certain pore or group of pores of a network to fill or remain filled with water during a wetting or drying process, respectively. This model is used to determine the equivalent stress which represents the stress supported by the solid skeleton of an unsaturated soil and is related to the strength of the material. The probabilistic model is an alternative to the use of computational models and shows some important advantages. The theoretical results of the model are compared with a series of triaxial tests performed at constant suction and constant volume. These comparisons demonstrate that this model is adequate to establish the strength of unsaturated materials. © 2010 Elsevier Ltd. All rights reserved.
Mucino V.H.,West Virginia University |
Lozano Guzman A.A.,Instituto Polit Ecnico Nacional |
Alcazar Farias E.K.,University Autnoma Of Quertaro |
Sanchez-Goni E.,West Virginia University |
Navarrete I.A.,Instituto Polit Ecnico Nacional
ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) | Year: 2012
Global competencies of engineering graduates have been identified as traits that are increasingly necessary for professional competitiveness of graduates, but continue to be elusive and difficult to address in the engineering curricula. Study abroad and experiential learning programs have been invoked to address some of the global competencies with varied degrees of success. In this paper, a faculty-led program model developed by West Virginia University and several institutions in Mexico and the US is presented, in which senior engineering students from the US and Mexico team up to conduct meaningful engineering projects in industry in Mexico. Intermixed teams of students are formed and placed in various industrial sites to work full time under the advice of engineering practitioners and faculty members from both Mexico and USA. Global competencies are addressed in the context of a project that requires students to work with peers of similar disciplines and level across language and cultural barriers. Copyright © 2012 by ASME.
Gmez-Snchez M.,University Autnoma Of Quertaro |
Cabrera-Luna A.,University Autnoma Of Quertaro |
Gonzlez-Elizondo M.S.,Centro Interdisciplinario Of Investigacin Para El Desarrollo Integral Regional |
Reznicek A.A.,University of Michigan
Systematic Botany | Year: 2012
Carex vizarronensis, a new species from Cadereyta de Montes in the Mexican state of Queretaro, is described and illustrated. The new species is distinguished from C. schiedeana by its densely papillose culms, leaves and inflorescence bracts, and, perigynia with a corky stipe. © Copyright 2012 by the American Society of Plant Taxonomists.