The invention provides novel compositions and methods for improving the transformation of monocot seed excised embryo explants, which may include one or more steps of explant preparation, explant rehydration, Rhizobiales bacterium inoculation and co-culture, bud induction, extended bud induction, or regeneration of genetically modified plants or plant parts. The methods provided herein may include transforming at least one plant cell of the embryo explant with a heterologous polynucleotide by inoculating the embryo explant with a Rhizobiales bacterium comprising the heterologous polynucleotide. The methods provided herein also include methods of regenerating a genetically modified plant or plant part from a transformed or edited plant cell or explant.