Abstract: The present invention provides methods for chemical selection of female gametes that do not contain a transgene of interest in plants. The methods result is increased efficiency of a breeding program to provide increased trait purity by ensuring that inbreds and plants are homozygous for a transgene of interest. Herbicides such as glyphosate can be used as the chemical gametocide to selectively eliminate female gametes that do not contain the gene conferring glyphosate resistance, resulting in seed or progeny substantially homozygous for such herbicide resistance on a large scale in a single generation.