Untitled

Bellon, Mauricio R.; Berthaud, Julien; Smale, Mélinda; Aguirre, J. A.; Taba, Suketoshi; Aragón, Flavio; Diaz, Joseph; Castro, Hugo

doi:10.1023/a:1023967611495

Cited by 77 publications

(9 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A portion of this landrace diversity is housed in seed collections, such as the germplasm collection at the International Maize and Wheat Improvement Center (www.cimmyt.org). However, a much larger and more dynamic source of genetic diversity resides in the evolving populations of maize that are repeatedly mixed and selected by individual farmers (11,12,21,22). Although it is unlikely that the presence of a few transgenes would reduce the genetic diversity of these populations to a greater extent than gene flow from non-GM modern cultivars, transgenes have been perceived as a threat to the crop's cultural identity by local farmers (4,12).…”

Section: Resultsmentioning

confidence: 99%

“…Maize plays a central role in the diet and culture of Mexican society, and approximately two-thirds of the maize grown in Mexico consists of landraces (4,11,12). Further monitoring of transgene introgression is warranted because there are many routes by which novel transgenes could potentially spread and multiply within and among maize populations (4,11,12,21,22). Worldwide, the ability of transgenes to disperse among countries merits closer scientific monitoring, especially when the receiving country has not approved them for environmental release, and in cases when the genetic modification eliminates or impairs the use of a particular crop as food.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Absence of detectable transgenes in local landraces of maize in Oaxaca, Mexico (2003–2004)

Ortiz-García

Ezcurra

Schoel

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

104

View full text Add to dashboard Cite

In 2000, transgenes were detected in local maize varieties (landraces) in the mountains of Oaxaca, Mexico [Quist, D. & Chapela, I. H. (2001) Nature 414, 541–543]. This region is part of the Mesoamerican center of origin for maize ( Zea mays L.), and the genetic diversity that is maintained in open-pollinated landraces is recognized as an important genetic resource of great cultural value. The presence of transgenes in landraces was significant because transgenic maize has never been approved for cultivation in Mexico. Here we provide a systematic survey of the frequency of transgenes in currently grown landraces. We sampled maize seeds from 870 plants in 125 fields and 18 localities in the state of Oaxaca during 2003 and 2004. We then screened 153,746 sampled seeds for the presence of two transgene elements from the 35S promoter of the cauliflower mosaic virus and the nopaline synthase gene (nopaline synthase terminator) from Agrobacterium tumefaciens . One or both of these transgene elements are present in all transgenic commercial varieties of maize. No transgenic sequences were detected with highly sensitive PCR-based markers, appropriate positive and negative controls, and duplicate samples for DNA extraction. We conclude that transgenic maize seeds were absent or extremely rare in the sampled fields. This study provides a much-needed preliminary baseline for understanding the biological, socioeconomic, and ethical implications of the inadvertent dispersal of transgenes from the United States and elsewhere to local landraces of maize in Mexico.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Absence of detectable transgenes in local landraces of maize in Oaxaca, Mexico (2003–2004)

Ortiz-García

Ezcurra

Schoel

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

104

View full text Add to dashboard Cite

show abstract

“…Asian farmers have been cultivating thousands of rice landraces with different aromas, tastes, medicinal properties and cultural values to meet their culinary and cultural requirements [28]. Mexican farmers in the Oaxaca region plant 11 different corn landraces used to produce 9 different types of dishes [29]. Traditional crop varieties in Ethiopia including African millet ( Eleusine coracana ), wheat ( Triticum turgidum ) [30] and barley [31] are well preserved to meet the needs of traditional local food cultures.…”

Section: Introductionmentioning

confidence: 99%

Influence of ethnic traditional cultures on genetic diversity of rice landraces under on-farm conservation in southwest China

Wang

Wang²,

Sun

et al. 2016

J Ethnobiology Ethnomedicine

View full text Add to dashboard Cite

BackgroundCrop genetic resources are important components of biodiversity. However, with the large-scale promotion of mono-cropping, genetic diversity has largely been lost. Ex-situ conservation approaches were widely used to protect traditional crop varieties worldwide. However, this method fails to maintain the dynamic evolutionary processes of crop genetic resources in their original habitats, leading to genetic diversity reduction and even loss of the capacity of resistance to new diseases and pests. Therefore, on-farm conservation has been considered a crucial complement to ex-situ conservation. This study aimed at clarifying the genetic diversity differences between ex-situ conservation and on-farm conservation and to exploring the influence of traditional cultures on genetic diversity of rice landraces under on-farm conservation.MethodsThe conservation status of rice landrace varieties, including Indica and Japonica, non-glutinous rice (Oryza sativa) and glutinous rice (Oryza sativa var. glutinosa Matsum), was obtained through ethno-biology investigation method in 12 villages of ethnic groups from Guizhou, Yunnan and Guangxi provinces of China. The genetic diversity between 24 pairs of the same rice landraces from different times were compared using simple sequence repeat (SSR) molecular markers technology. The landrace paris studied were collected in 1980 and maintained ex-situ, while 2014 samples were collected on-farm in southwest of China.ResultsThe results showed that many varieties of rice landraces have been preserved on-farm by local farmers for hundreds or thousands of years. The number of alleles (Na), effective number of alleles (Ne), Nei genetic diversity index (He) and Shannon information index (I) of rice landraces were significantly higher by 12.3–30.4 % under on-farm conservation than under ex-situ conservation. Compared with the ex-situ conservation approach, rice landraces under on-farm conservation programs had more alleles and higher genetic diversity. In every site we investigated, ethnic traditional cultures play a positive influence on rice landrace variety diversity and genetic diversity.ConclusionMost China’s rice landraces were conserved in the ethnic areas of southwest China. On-farm conservation can effectively promote the allelic variation and increase the genetic diversity of rice landraces over the past 35 years. Moreover, ethnic traditional culture practices are a crucial foundation to increase genetic diversity of rice landraces and implement on-farm conservation.Electronic supplementary materialThe online version of this article (doi:10.1186/s13002-016-0120-0) contains supplementary material, which is available to authorized users.

show abstract

“…While efforts such as the Svalbard Global Seed Vault and other germplasm repositories seek to safeguard the agricultural treasures of the world, they represent a static picture of diversity and often can marginalize the dynamic process of farmers whose activities generate and maintain diversity. The role of farmer selection in the creation and maintenance of crop diversity has only recently been investigated in staple crops such as wheat, maize, potatoes, and cassava (Abay et al 2008; Bellon 1996; Bellon et al 2003; Brush and Meng 1998; Cleveland et al 2000; Dyer and Taylor 2008; Jarvis and Hodgkin 1999; Louette and Smale 2000; Perales et al 2003). To date there have been limited attempts to examine their role in creating and conserving diversity in horticultural crops.…”

Section: Introductionmentioning

confidence: 99%

Different Seed Selection and Conservation Practices for Fresh Market and Dried Chile Farmers in Aguascalientes, Mexico

2010

View full text Add to dashboard Cite

Different Seed Selection and Conservation Practices for Fresh Market and Dried Chile Farmers in Aguascalientes, Mexico. The process of selecting and saving seed is the most basic and oldest of agricultural practices. In today’s modern and highly capital-intensive agriculture, seeds are often treated like another chemical input. This study sought to examine seed selection and saving practices among chile farmers in Aguascalientes, Mexico, where both industrial and traditional agriculture are practiced. We observed a clear division among farmers who plant chile peppers commercially. Sixty-eight chile pepper farmers were surveyed in order to document seed selection and saving practices. Fifteen respondents (22%) planted chile peppers destined for the fresh market and all utilized purchased commercial seed of F1 hybrid varieties. Fifty-three farmers (78%) planted chiles to be dried and either saved their own or purchased seeds that others had saved and selected. Farmers who saved their own seed sought to maintain an ideotype, rather than directionally select for certain traits, much like Cleveland et al. (2000) chronicled in central Mexican maize farmers. Farmers would benefit from a participatory plant-breeding program in order to maintain productive seed stock for the continued cultivation of dried chile pepper in the state.

show abstract

Untitled

Cited by 77 publications

References 21 publications

Absence of detectable transgenes in local landraces of maize in Oaxaca, Mexico (2003–2004)

Absence of detectable transgenes in local landraces of maize in Oaxaca, Mexico (2003–2004)

Influence of ethnic traditional cultures on genetic diversity of rice landraces under on-farm conservation in southwest China

Different Seed Selection and Conservation Practices for Fresh Market and Dried Chile Farmers in Aguascalientes, Mexico

Contact Info

Product

Resources

About