A genetic screen for Arabidopsis mutants displaying a hyper-susceptible to Agrobacterium transformation (hat) phenotype was performed. The gene disrupted in the hat3 mutant encodes a putative myb-family transcription factor (MTF) that negatively regulates susceptibility to Agrobacterium-mediated transformation. Over-expression of an integrin-like protein results in plants that are hyper-susceptible to transformation. Manipulation of MTF, members of this protein family, and members of the integrin domain-like protein family for example At14a allows improved control of Agrobacterium transformation, including in crops.