<i>Gossypium barbadense</i> maintenance and coexistence in situ with genetically modified cotton in the state of Mato Grosso, Brazil

Abstract

The objective of this work was to determine which cotton genetic resources are present in the state of Mato Grosso, Brazil, to assess the risks associated with the in situ conservation of these materials, including gene flow from genetically modified (GM) crops, and to determine the effectiveness of the exclusion zones for genetically modified cotton. Four expeditions were performed inside and outside the exclusion zones, to collect geographical and morphological data, as well as the use of these species by the population, and data on the in situ maintenance practices at each site. The presence of GM proteins was determined in some plants within the exclusion zones, and in all plants outside the exclusion zones. Gossypium barbadense was the most frequent species, primarily cultivated in urban and rural backyards for medicinal purposes. No evidence of hybridization with G. hirsutum was observed, based on morphology or on GM protein expression, even in regions with long-term coexistence. The species G. barbadense is the most important cotton genetic resource in Mato Grosso state. The exclusion zones are not necessary to protect the genetic diversity of the species in the state. The decline of medicinal use of the species is the primary threat to its conservation, and preservation efforts should focus on maintaining its traditional uses.