Gene Flow Between Crops and their Wild Relatives
News Mar 15, 2010
New Book by Meike S. Andersson and M. Carmen de Vicente, ; Funded by GTZ and collaboration with CIAT and Universidad del Valle (Cali, Colombia)
The centres of origin and diversity of many crop species are located in developing countries. Many of these areas are not only under the pressure of environmental threats, but they are also affected by agriculture, and in particular by the way it is practiced.
Modern agriculture has made great strides to improve productivity, but is dependent on massive use of agricultural inputs, creating environmental problems. Biotech tools and genetically engineered crops are seen as possible solutions to overcome production constraints faced by many poor farmers, while at the same time overcoming environmental problems reducing the use of inputs. However, there are concerns about the likelihood for geneflow from GM varieties to wild populations, especially in centres of origin and diversity of crop plants.
The objective of this project was to provide support tools to assist in making well-informed decisions about the ecological implications of releasing GM crops in or around areas with concentrated crop diversity.
It focused on one particular concern that is of utmost importance in this respect: The likelihood of gene flow and introgression to crop wild relatives (CWR) and other domesticated species.
The goal was to provide objective information to guide basic and scientifically sound decision-making by taking into account the facts that gene flow and introgression exist, and that the preservation of crop genetic resources in their habitat is a requisite for the sustainable development of modern crops.
Specifically, the project produced the following three outputs:
* A book “Gene Flow Between Crops and Their Wild Relatives”, published by Johns Hopkins;
* World Maps of Crop Wild Relatives (CWR) and Gene Introgression;
* A Database of Gene Flow Bibliography.
(Clickable link to above at http://www.bioversityinternational.org/scientific_information/themes/conservation_and_use/gene_flow_project.html )
The work summarizes both state-of-the-art knowledge and research gaps related to gene flow and introgression between crops and their wild relatives.
The information is based on a comprehensive review of the relevant scientific and technical literature. It emphasizes gene transfer from GM crops to wild species, rather than between different cultivars (i.e., from GM to conventional varieties) of the same crop.
The 20 crop chapters are divided into the following sections:
* General biological information (crop's scientific name, its center(s) of origin and diversity, flowering, pollen dispersal and longevity, sexual and vegetative reproduction, seed dispersal and dormancy, the existence and persistence of volunteers and feral plants, and the existence of weeds and their invasiveness potential);
* Presentation of the most important CWR (information about their ploidy levels, diverse genomes, centers of origin, and geographic distribution);
* Assessment of the crop's potential for hybridization with its wild relatives (relevant studies and literature);
* Pollen flow studies related to pollen dispersal distances and hybridization rates (and recommended separation distances);
* Overview summarizing the state of development of GM technology (global GM crop area, GM traits currently researched for the crop, and countries where GM varieties are grown commercially or in field trials)
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