title: Detection of transgenes in local maize varieties of small-scale farmers in eastern cape, South Africa.
abstract: Small-scale subsistence farmers in South Africa have been introduced to genetically modified (GM) crops for more than a decade. Little is known about i) the extent of transgene introgression into locally recycled seed, ii) what short and long-term ecological and socioeconomic impacts such mixing of seeds might have, iii) how the farmers perceive GM crops, and iv) to what degree approval conditions are followed and controlled. This study conducted in the Eastern Cape, South Africa, aims primarily at addressing the first of these issues. We analysed for transgenes in 796 individual maize plants (leaves) and 20 seed batches collected in a village where GM insect resistant maize was previously promoted and grown as part of an governmental agricultural development program over a seven year period (2001-2008). Additionally, we surveyed the varieties of maize grown and the farmers' practices of recycling and sharing of seed in the same community (26 farmers were interviewed). Recycling and sharing of seeds were common in the community and may contribute to spread and persistence of transgenes in maize on a local or regional level. By analysing DNA we found that the commonly used transgene promoter p35s occurred in one of the 796 leaf samples (0.0013%) and in five of the 20 seed samples (25%). Three of the 20 seed samples (15%) included herbicide tolerant maize (NK603) intentionally grown by the farmers from seed bought from local seed retailers or acquired through a currently running agricultural development program. The two remaining positive seed samples (10%) included genes for insect resistance (from MON810). In both cases the farmers were unaware of the transgenes present. In conclusion, we demonstrate that transgenes are mixed into seed storages of small-scale farming communities where recycling and sharing of seeds are common, i.e. spread beyond the control of the formal seed system.
authors.affiliation: GenØk -Centre for Biosafety, Tromsø, Norway.
authors.forename: Marianne
authors.initials: M
authors.lastname: Iversen
authors.affiliation: GenØk -Centre for Biosafety, Tromsø, Norway.
authors.forename: Idun M
authors.initials: IM
authors.lastname: Grønsberg
authors.affiliation: Unit for Environmental Sciences and Development, North-West University, Potchefstroom, South Africa.
authors.forename: Johnnie
authors.initials: J
authors.lastname: van den Berg
authors.affiliation: Department of Urban and Rural Development, Swedish University of Agricultural Sciences, Uppsala, Sweden.
authors.forename: Klara
authors.initials: K
authors.lastname: Fischer
authors.affiliation: College of Agriculture and Natural Sciences, School of Biological Sciences, University of Cape Coast, Cape Coast, Ghana.
authors.forename: Denis Worlanyo
authors.initials: DW
authors.lastname: Aheto
authors.affiliation: GenØk -Centre for Biosafety, Tromsø, Norway; Faculty of Health Sciences, UIT The Arctic University of Norway, Tromsø, Norway.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bøhn
mesh_terms: D000383:Agriculture / Q000379:methods*; D018556:Crops, Agricultural / Q000235:genetics*; D030821:Plants, Genetically Modified; D016133:Polymerase Chain Reaction / Q000379:methods; D012639:Seeds / Q000235:genetics*; D011795:Surveys and Questionnaires; D019076:Transgenes; D003313:Zea mays / Q000235:genetics*