Search Results for: Mexico

Abstract: The peasant economy of the Yucatan Peninsula is sustained by agriculture and beekeeping. Honey production has great economic importance, given that it represents the main source of income for Mayan rural families. Furthermore, Mexico is the world’s fourth‐largest exporter of honey. The honey comes from jungle that covers the peninsular territory and forms part …

Abstract: In Mexico, the Center of origin and diversity of maize, a daily per capita average of 0.5 kg of maize-based foods are consumed. Approximately 10 million tons of maize is produced in small peasant holdings. Nevertheless, a greater proportion of industrially produced maize-derived products have started to appear in recent years. We traced the …

Abstract: Using precise pollen species determination by conventional microscopic methods, accompanied by molecular genetic markers, we found bees collect GMO (genetically modified) soybean pollen and incorporate it in Yucatan honey. Honey comb samples from Las Flores, Campeche, Mexico, often contained soybean pollen. Pollen in honey was analyzed in nine samples; six contained substantial soy pollen …

Abstract: Objectives. Current models of transgene dispersal focus on gene flow via pollen while neglecting seed, a vital vehicle for gene flow in centers of crop origin and diversity. We analyze the dispersal of maize transgenes via seeds in Mexico, the crop’s cradle. Methods. We use immunoassays (ELISA) to screen for the activity of recombinant …

Abstract: Transgenic crop varieties (TGVs) are being promoted as essential for improving small-scale Third World (SSTW) agriculture. Most economic research on this topic makes critical, untested assumptions, including that farmers will choose TGVs over other varieties because TGVs are economically optimal and because farmers are risk neutral profit maximizers. We tested these assumptions using data …

Abstract: Our original publication contained two separate conclusions derived from two methodological approaches. First, using PCR, we detected the presence of three distinct transgenic DNA sequences in maize landraces in Oaxaca, Mexico. Second, we attempted to establish the genomic context of transgene insertion using i-PCR. The criticisms raised by Metz and Fütterer and by Kaplinsky …

Abstract: In 2003, the environmental authorities of the Federal District of Mexico declared that genetically modified organisms were incompatible with ecological agriculture practices established in rural areas south of Mexico City. To ensure compliance with official standards and organic agriculture policies, steps were taken to implement an early warning system for the detection of genetically …

Abstract: Glyphosate is an agrochemical widely used to control weeds. However, glyphosate spreads to water bodies by spray-drift, run-off and leaching, potentially causing detrimental effects on non-target biota. There is no information on the occurrence of this herbicide in water bodies near crop fields in Mexico, although it is the most commonly used pesticide in …

Abstract: Concerns have been raised about the potential effects of transgenic introductions on the genetic diversity of crop landraces and wild relatives in areas of crop origin and diversification, as this diversity is considered essential for global food security. Direct effects on non-target species, and the possibility of unintentionally transferring traits of ecological relevance onto landraces …

Abstract: Field, greenhouse, and laboratory experiments were conducted to investigate resistance to glyphosate in tropical sprangletop biotypes (Lv8 and Lv9) collected in Persian lime from Veracruz, Mexico. Assays to determine the dose required to reduce seedling fresh weight by 50% indicated a resistance factor (RF) of 4.9 and 3.2 for biotypes Lv8 and Lv9, respectively; …

Abstract: The aim of this study was to generate an easy to use index to evaluate the ecological state of agricultural land from a sustainability perspective. We selected environmental indicators, such as the use of organic soil amendments (green manure) versus chemical fertilizers, plant biodiversity (including crop associations), variables which characterize soil conservation of conventional …

Abstract: We used aerial photographs, satellite images, and field surveys to monitor forest cover in the core zones of the Monarch Butterfly Biosphere Reserve in Mexico from 2001 to 2012. We used our data to assess the effectiveness of conservation actions that involved local, state, and federal authorities and community members (e.g., local landowners and …

Abstract: 1. During the 2009–2010 overwintering season and following a 15‐year downward trend, the total area in Mexico occupied by the eastern North American population of overwintering monarch butterflies reached an all‐time low. Despite an increase, it remained low in 2010–2011. 2. Although the data set is small, the decline in abundance is statistically significant using both …

Abstract: Samples of rice from Mexican and USA retail stores were analyzed for the presence of transgenic (GM) events using real-time PCR. In screening for the CaMV35S promoter sequence (35SP), positive results were found in 49 and 35% of the Mexican and American samples, respectively. In further investigations in Mexican samples, 43% were positive for …

Text: In their letter (25 Feb., p. 1399), J. P. R. Martínez-Soriano and D. S. Leal-Klevezas say that there “should be no need for concern” that the introduction of transgenic maize varieties in Mexico may pose a risk to landraces or wild relatives of maize in its ancestral home. However, it would be a mistake …

Abstract: The Genetic Modified Organisms (GMO) or transgenics could harm human and animal health and represent a potential danger to biodiverse countries. Particularly delicate is its use in a country such as Mexico, where corn and beans are originated, plants which have been converted into a food item all over the world. As to social aspects, …

Abstract: A possible consequence of planting genetically modified organisms (GMOs) in centres of crop origin is unintended gene flow into traditional landraces. In 2001, a study reported the presence of the transgenic 35S promoter in maize landraces sampled in 2000 from the Sierra Juarez of Oaxaca, Mexico. Analysis of a large sample taken from the …

Abstract: Over 95% of the currently cultivated cotton was domesticated from Gossypium hirsutum, which originated and diversified in Mexico. Demographic and genetic studies of this species at its centre of origin and diversification are lacking, although they are critical for cotton conservation and breeding. We investigated the actual and potential distribution of wild cotton populations, …

Abstract: Threats to migratory animals can occur at multiple periods of the annual cycle that are separated by thousands of kilometres and span international borders. Populations of the iconic monarch butterfly (Danaus plexippus) of eastern North America have declined over the last 21 years. Three hypotheses have been posed to explain the decline: habitat loss …

Abstract: Gene flow is a potential concern associated with the use of transgenic crops because it could affect genetic diversity of related landraces and wild relatives. This concern has taken on added importance with the looming introduction of transgenic crops in centers of crop domestication (Mexico, China) and those producing pharmaceutical compounds. For gene flow …

Abstract: Data have been lacking on the proportion of Helicovera zea larvae that develop on noncotton host plants that can serve as a refuge from selection pressure for adaptation to transgenic cotton varieties that produce a toxin from the bacterium Bacillus thuringiensis. We found that individual H. zea moths that develop as larvae on cotton …

Abstract: Pesticides have been implicated in widespread amphibian declines. We assessed acute and chronic toxicity of two widely used herbicides to larval New Mexico (Spea multiplicata) and Plains (S. bombifrons) spadefoots from cropland and native grassland playas. Roundup WeatherMAX® (WM) toxicity estimates (48- and 216-h LC50; 48-h LC1) for both species were similar to environmental …