[Bt gene flow of transgeic cotton]

Area of Science:

• Agricultural Science
• Genetics
• Ecology

Context:

• Assessing the ecological impact of genetically modified crops is crucial for environmental safety.
• Understanding gene flow in transgenic cotton ( *Gossypium hirsutum* ) is vital for risk assessment in agricultural ecosystems.
• The study focuses on the Chinese ecological environment, a significant region for cotton cultivation.

Purpose:

• To quantify the extent and patterns of gene flow from transgenic cotton (GK-12) to non-transgenic cultivars (CCRC 12, Xinmian 13).
• To evaluate the influence of distance and transgenic crop diversity on engineered gene dispersal.
• To determine the potential for gene flow to wild relatives and establish effective buffer zone recommendations.

Summary:

• Gene flow was detected up to 36 meters from the transgenic cotton plot, with significantly higher rates observed within the 0-6 meter range.
• Bt gene flow increased with transgenic cotton diversity at closer distances (3-6m) but showed minimal increase at greater distances.
• Gene flow between cotton species was lower than between cultivars but extended to 72 meters, suggesting interspecific gene flow potential.

Impact:

• Findings indicate that a 72-meter buffer zone could effectively limit gene flow from small-scale field tests of transgenic cotton.
• The study highlights the importance of considering both cultivar and species gene flow when assessing the environmental risks of GMOs.
• Results contribute to the development of biosafety guidelines for transgenic crop deployment in diverse agricultural landscapes.