Methodology is provided for the production of uniformly transformed plants capable of transmitting a foreign gene to progeny by sexual reproduction. A foreign gene is introduced into the zygote in an isolated embryo sac and a transformed plant is recovered. Alternatively, a foreign gene is introduced into an egg cell in an isolated embryo sac, the egg cell is fertilized with an isolated sperm cell and a transformed plant is recovered. Sperm cells may be transformed with a foreign gene, an egg cell in an isolated embryo sac is fertilized with the transformed sperm cells, or nuclei isolated from the transformed sperm cells, and a transgenic plant is recovered. Another method for the production of transgenic plants is transformation of an embryo in an isolated embryo sac. The transgenic plant produced by any one of these methods is homogeneously transformed and capable of transmitting the foreign gene to progeny by sexual reproduction.