Author : Louette, Dominique

Summary : The results herein are intended to contribute to discussions on the risk of transgenic varieties to the genetic structure of teosinte populations and landraces in Mexico. The study presented is part of research in Mexico on the conservation in situ of local varieties of cultivated plants (Loutte 1994). This report attempts to describe the mechanisms that underlie the structure and dynamics of diversity in a traditional agrosystem by characterizing the diversity of maize varieties cultivated, traditional management practices, and their effects on genetic structure. On the other hand, the data also provide evidence of the importance of gene flow between varieties, indicating to what extent traditional systems encourage or restrict this flow, and therefore to what extent a variety introduced may have an effect on the genetic structure of landraces.