Low frequency of transgene flow from Bt/CpTI rice to its nontransgenic counterparts planted at close spacing

Authors

  • Jun Rong,

    1. The Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Shanghai 200433, China;
    Search for more papers by this author
  • Zhiping Song,

    1. The Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Shanghai 200433, China;
    Search for more papers by this author
  • Jun Su,

    1. Fujian Province Key Laboratory of Genetic Engineering for Agriculture, Fujian Academy of Agricultural Sciences, Fuzhou 350003, China
    Search for more papers by this author
  • Hui Xia,

    1. The Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Shanghai 200433, China;
    Search for more papers by this author
  • Bao-Rong Lu,

    Corresponding author
    1. The Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Shanghai 200433, China;
      Authors for correspondence: Bao-Rong Lu and Feng Wang Tel: +86 21 65643668 (B-RL) Fax: +86 21 65643668 (B-RL) Email: brlu@fudan.edu.cn (B-RL); wf@fjage.org (FW)
    Search for more papers by this author
  • Feng Wang

    Corresponding author
    1. Fujian Province Key Laboratory of Genetic Engineering for Agriculture, Fujian Academy of Agricultural Sciences, Fuzhou 350003, China
      Authors for correspondence: Bao-Rong Lu and Feng Wang Tel: +86 21 65643668 (B-RL) Fax: +86 21 65643668 (B-RL) Email: brlu@fudan.edu.cn (B-RL); wf@fjage.org (FW)
    Search for more papers by this author

Authors for correspondence: Bao-Rong Lu and Feng Wang Tel: +86 21 65643668 (B-RL) Fax: +86 21 65643668 (B-RL) Email: brlu@fudan.edu.cn (B-RL); wf@fjage.org (FW)

Summary

  • • Crop-to-crop transgene flow will affect seed purity of non-GM rice varieties, leading to unwanted consequences. To assess the maximum probability of transgene outflow in rice (Oryza sativa), gene flow experiments were conducted with three cultivation patterns with different mixed-planting proportions of adjacent GM and non-GM rice at two sites in Fujian and Hainan Provinces of China.
  • • Three GM rice lines containing two insect-resistance genes (Bt/CpTI) and their non-GM counterparts were used in the experiments to allow natural hybridization to occur. A hygromycin resistance gene was used as a selective marker for identifying hybrids.
  • • Based on the examination of > 645 700 geminated seeds, the result showed low frequencies (0.05–0.79%) of transgene flow from GM to non-GM rice at close spacing, although with significant variation among mixed-planting proportions.
  • • It is concluded that rice transgene flow will occur at a very low frequency (< 1.0%), even if the GM rice is planted at close spacing with non-GM rice, and high densities of GM rice cultivated in the neighborhood of non-GM rice will increase the probability of outcrossing with the non-GM rice.

Ancillary