USDA-ARS U.S. National Poultry Research Center 1 article published in JoVE Genetics Rapid Deletion Production in Fungi via Agrobacterium Mediated Transformation of OSCAR Deletion Constructs Scott E. Gold1, Zahi Paz2, María D. García-Pedrajas3, Anthony E. Glenn1 1Toxicology and Mycotoxin Research Unit, NPRC, USDA-ARS, 2Hazera Seeds LTD, Brurim, 3Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora” - Universidad de Málaga - Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Estación Experimental “La Mayora” Gene deletion mutants generated through homologous recombination are the gold standard for gene function studies. The OSCAR (One Step Construction of Agrobacterium-Recombination-ready-plasmids) method for rapid generation of deletion constructs is described. Agrobacterium mediated fungal transformation follows. Finally, a PCR based confirmation method of gene deletions in fungal transformants is presented.