Yuan-Chih Su1, Po-Shung Wang1, Jhih-Ling Yang1, Hong Hong1, Tzu-Kai Lin2, Yuan-Kai Tu1,3, Bo-Jein Kuo4,5. 1. Department of Agronomy, National Chung Hsing University, No. 145 Xingda Road, South District, Taichung City, 40227, Taiwan (R.O.C.). 2. Division of Crop Science, Taiwan Agricultural Research Institute, No. 189, Zhongzheng Road, Wufeng District, Taichung City, 41362, Taiwan (R.O.C.). 3. Division of Biotechnology, Taiwan Agricultural Research Institute, No. 189, Zhongzheng Road, Wufeng District, Taichung City, 41362, Taiwan (R.O.C.). 4. Department of Agronomy, National Chung Hsing University, No. 145 Xingda Road, South District, Taichung City, 40227, Taiwan (R.O.C.). bjkuo@nchu.edu.tw. 5. Innovation and Development Center of Sustainable Agriculture (IDCSA), National Chung Hsing University, No. 145 Xingda Road, South District, Taichung City, 40227, Taiwan (R.O.C.). bjkuo@nchu.edu.tw.
Abstract
BACKGROUND: The cropping area of genetically modified (GM) crops has constantly increased since 1996. However, currently, cultivating GM crops is associated with many concerns. Transgenes are transferred to non-GM crops through pollen-mediated gene flow, which causes environmental problems such as superweeds and introgressive hybridization. Rapeseed (Brassica napus L.), which has many GM varieties, is one of the most crucial oil crops in the world. Hybridization between Brassica species occurs spontaneously. B. rapa grows in fields as a weed and is cultivated as a crop for various purposes. Both B. rapa weeds and crops participate in gene flow among rapeseed. Therefore, gene flow risk and the coexistence of these two species should be studied. RESULTS: In this study, field experiments were conducted at two sites for 4 years to evaluate gene flow risk. In addition, zero-inflated models were used to address the problem of excess zero values and data overdispersion. The difference in the number of cross-pollination (CP) events was nonsignificant between upwind and downwind plots. The CP rate decreased as the distance increased. The average CP rates at distances of 0.35 and 12.95 m were 2.78% and 0.028%, respectively. In our results, zero-inflated negative binomial models were comprehensively superior to zero-inflated Poisson models. The models predicted isolation distances of approximately 1.36 and 0.43 m for the 0.9% and 3% threshold labeling levels, respectively. CONCLUSIONS: Cultivating GM crops is prohibited in Taiwan; however, the study results can provide a reference for the assessment of gene flow risk and the coexistence of these two species in Asian countries establishing policies for GM crops.
BACKGROUND: The cropping area of genetically modified (GM) crops has constantly increased since 1996. However, currently, cultivating GM crops is associated with many concerns. Transgenes are transferred to non-GM crops through pollen-mediated gene flow, which causes environmental problems such as superweeds and introgressive hybridization. Rapeseed (Brassica napus L.), which has many GM varieties, is one of the most crucial oil crops in the world. Hybridization between Brassica species occurs spontaneously. B. rapa grows in fields as a weed and is cultivated as a crop for various purposes. Both B. rapa weeds and crops participate in gene flow among rapeseed. Therefore, gene flow risk and the coexistence of these two species should be studied. RESULTS: In this study, field experiments were conducted at two sites for 4 years to evaluate gene flow risk. In addition, zero-inflated models were used to address the problem of excess zero values and data overdispersion. The difference in the number of cross-pollination (CP) events was nonsignificant between upwind and downwind plots. The CP rate decreased as the distance increased. The average CP rates at distances of 0.35 and 12.95 m were 2.78% and 0.028%, respectively. In our results, zero-inflated negative binomial models were comprehensively superior to zero-inflated Poisson models. The models predicted isolation distances of approximately 1.36 and 0.43 m for the 0.9% and 3% threshold labeling levels, respectively. CONCLUSIONS: Cultivating GM crops is prohibited in Taiwan; however, the study results can provide a reference for the assessment of gene flow risk and the coexistence of these two species in Asian countries establishing policies for GM crops.
Authors: Mike J Wilkinson; Luisa J Elliott; Joël Allainguillaume; Michael W Shaw; Carol Norris; Ruth Welters; Matthew Alexander; Jeremy Sweet; David C Mason Journal: Science Date: 2003-10-09 Impact factor: 47.728
Authors: Rebecca Weekes; Carola Deppe; Theo Allnutt; Caroline Boffey; Derek Morgan; Sarah Morgan; Mark Bilton; Roger Daniels; Christine Henry Journal: Transgenic Res Date: 2005-10 Impact factor: 2.788
Authors: S I Warwick; M-J Simard; A Légère; H J Beckie; L Braun; B Zhu; P Mason; G Séguin-Swartz; C N Stewart Journal: Theor Appl Genet Date: 2003-04-30 Impact factor: 5.699