The present invention provides methods and compositions which deliver Agrobacterium via microinjection directly into the embryo sac. At the time of injection, the embryo sac can comprise an egg cell, or alternatively, the embryo sac can be fertilized and comprise either a zygote or an embryo. Once inside the embryo sac, the Agrobacterium harboring a T-DNA having a polynucleotide of interest can express of the polynucleotide of interest in the plant. Further, the Agrobacterium can transfer the T-DNA having the polynucleotide of interest to the plant nucleus to produce a transformed plant. The polynucleotide of interest may be stably integrated into the genome of the egg cell, zygote, embryo, or endosperm, and any tissue, plant part, and/or plant generated therefrom.