Gene flow from herbicide-tolerant GM rice and the heterosis of GM rice-weed F2 progeny

Abstract

Gene flow from genetically modified (GM) crops to non-GM cultivars or weedy relatives may lead to the development of more aggressive weeds. We quantified the amount of gene flow from herbicide-tolerant GM rice (Protox GM, derived from the cultivar Dongjin) to three cultivars (Dongjin, Aranghyangchal and Hwaseong) and a weedy rice line. Gene flow frequency generally decreased with increasing distance from the pollen donor. At the shortest distance (0.5 m), we observed a maximum frequency (0.039%) of gene flow. We found that the cultivar Dongjin received the greatest amount of gene flow, with the second being weedy rice. Heterosis of F2 inbred progeny was also examined between Protox GM and weedy rice. We compared growth and reproduction between F2 progeny (homozygous or hemizygous for the Protox gene) and parental rice lines (GM and weedy rice). Here, transgene-homozygous F2 progeny was significantly taller and produced more seeds than the transgene-hemizygous F2 progeny and parental lines. Although the gene flow frequency was generally low, our results suggest that F2 progeny between GM and weedy relatives may exhibit heterosis.

Outcrossing potential between 11 important genetically modified crops and the Chilean vascular flora

“…Rice is a self‐compatible autogamous species that can lead to pollen‐mediated outcrosses if short cultivation distances between individuals are applied between cultivars or subspecies, or when their flowering periods overlap. Pollen‐mediated gene flow from GM to conventional rice cultivars was already reported, with percentages ranging from <0.2% between immediate neighbouring or mixed plants in a plot and up to <1% for more distant plots (Chun et al ., ; Jia et al ., ; Messeguer et al ., , ; Rong et al ., , ; Serrat et al ., ). Additionally, by the use of different experimental designs (i.e.…”

Rice transgene flow: its patterns, model and risk management

“…Experiment results have shown that the frequency of transgene flow to red rice is similar to that between cultivated rice, because they are primarily self‐pollinated (e.g. Chen et al ., ; Chun et al ., ; Messeguer et al ., ; Olguin et al ., ; Song et al ., b; Song et al ., ). Gealy et al .…”

“…Experiment results have shown that the frequency of transgene flow to red rice is similar to that between cultivated rice, because they are primarily self-pollinated (e.g. Chen et al, 2004;Chun et al, 2011;Messeguer et al, 2004;Olguin et al, 2009;Song et al, 2002b;Song et al, 2009). Gealy et al (2003) reviewed more than ten published papers on the rates of gene flow from cultivated rice to weedy rice and noted that typical rates of cropweed hybridization were in the range of 0%-1.00%.…”

Fitness correlates of crop transgene flow into weedy populations: a case study of weedy rice in China and other examples

“…As shown in Table 1, molecular markers (e.g. microsatellites) are also used to quantify of crop-to-weed and crop-to-wild gene flow (Messeguer et al 2004;Olguin et al 2009;Chun et al 2011;Jia et al 2014). Gene flow results collected from these experimental studies are the first step for assessing the impact of cropto-weed and crop-to-wild transgene flow in rice.…”