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Table 1 Unexpected effects that impact fitness in rice after GE plants are crossed into genetic backgrounds of weedy or cultivated rice

From: Risk assessment of genetically engineered plants that can persist and propagate in the environment

InsecticidalEnhanced relative performance of the crop-weed hybrids, taller plants, more tillers, panicles, and spikelets per plant, as well as higher 1 000-seed weight, compared with the weedy rice parents
Seeds from the F1 hybrids had higher germination rates and produced more seedlings than the weedy parents
Herbicide toleranceTransgenic F2 crop–weed hybrids produced 48–125% more seeds per plant than non-transgenic controls
Transgenic hybrids also had higher EPSPS protein levels, tryptophan concentrations, photosynthetic rates, and per cent seed germination compared with non-transgenic controls
Findings suggest that overexpression of a native rice EPSPS gene can lead to fitness advantages, even without exposure to glyphosate
InsecticidalTransgenes can significantly alter the segregation distortion pattern in hybrid progeny, particularly the direction of segregation deviated according to different parents. Transgenes with strong selection advantages may have evolutionary impacts on hybrid progeny by changing their pattern of allelic segregation distortion after introgression from transgenic crops to wild relatives through hybridisation[45]
InsecticidalWeedy rice has increased fitness after the introgression of Bacillus thuringiensis (Bt) genes from cultivated rice[17]
InsecticidalIncrease of Bt content in some hybrids of wild rice and cultivated rice[46]
InsecticidalLower insect damage and higher fecundity in hybrids[47]
Herbicide toleranceTransgenic hybrid lineages showed significantly earlier tillering and flowering, as well as increased fecundity and overwintering survival/regeneration abilities[34]
Herbicide toleranceFitness of feral progeny was significantly higher after introgression from weedy rice to glufosinate-resistant transgenic hybrid rice[48]
Herbicide tolerance and insecticidalFitness of progeny in cultivated rice and weedy rice was found to depend on the environment, selective pressure and genetic background[27]