Disclosed are methods for transformation of an androgenic-derived, haploid cell line with a site-specific nuclease. In some embodiments, the androgenic-derived, haploid cell line is a maize microspore-derived plant tissue culture. In addition, the disclosure provides a method for modifying, e.g., by mutating or targeting and integrating donor DNA into, a specific locus of a haploid or dihaploid tissue genome. The disclosure further provides methods for regenerating a whole plant from the haploid or dihaploid tissue that contains either the mutation at a specific genomic locus or a donor DNA integrated within a specific genomic locus may be obtained from the subject disclosure.
