%0 Journal Article %T Rationalizing the isolation distance needed for field trials involving genetically modified rapeseed (Brassica napus L.) in China %A XiangXiang Zhao %A Tang Tang %A GuiMin Chen %A FuXia Liu %A XingLong Wang %A CuiPing Bu %A ChangMing Lu %J Chinese Science Bulletin %@ 1861-9541 %D 2013 %I %R 10.1007/s11434-012-5595-z %X The isolation distance required for field trials of genetically modified (GM) rapeseed varies widely worldwide, with a 50¨C400 m distance in most nations contrasting with a minimum 1000-m isolation distance in China. The goal of this study was to evaluate the relevance of current regulations in China regarding the isolation distance needed for GM rapeseed trials. A pollen flow experiment was conducted based on the design of concentric circles, with the GM plants in a 20-m diameter circle at the centre, surrounded by non-GM plants to a distance 60 m from the perimeter of the circle containing GM plants. The rate of pollen flow was the highest at the isolation distance of 0.5 m, where it ranged from 2.3091% to 2.6711%. The general pattern of the pollen flow rate (y) with distance (x) was well described by the equation y = 1.3936x 0.9136 (R 2 = 0.9950). The long-distance pollen flow tested at the isolation distance of 800 m was 0.0018%, which agrees with the theoretical prediction. The results suggested that 300 m, rather than 1000 m, is a reasonable distance to ensure a tolerable threshold of pollen flow (less than 0.01%) under conditions of winter rapeseed production in China. %K regulated isolation distance %K genetically modified winter rapeseed %K pollen flow rate %K tolerance threshold %U http://link.springer.com/article/10.1007/s11434-012-5595-z