The use of a needle injection method to inoculate maize and teosinte plants with the biotrophic pathogen Ustilago maydis is described. The needle injection inoculation method facilitates the controlled delivery of the fungal pathogen in between the plant leaves where the pathogen enters the plant through the formation of appresoria. This method is highly efficient, enabling reproducible inoculations with U. maydis.
Chavan, S., Smith, S. M. A Rapid and Efficient Method for Assessing Pathogenicity of Ustilago maydis on Maize and Teosinte Lines. J. Vis. Exp. (83), e50712, doi:10.3791/50712 (2014).