The benzoxazolinone class of phytoalexins are released by wheat, maize and rye upon pathogen attack. Benzoxazolinones have antimicrobial activity, but certain fungi have evolved mechanisms to actively detoxify these compounds, which may contribute to the virulence of these pathogens. In many Fusarium spp. a cluster of genes is thought to be involved in the detoxification of benzoxazolinones. However, only one enzyme, Fusarium Detoxification of Benzoxazolinone 2 (Fdb2), encoded in the cluster has been unequi vocally assigned a role in this process. The FDB2 gene encodes a N-malonyltransferase and was identified in the maize pathogen F. verticillioides. In this thesis, through comparative genome analysis of several Fusarium species, a conserved genomic region has been identified around FDB2. Expression analyses demonstrated that a cluster of nine genes were responsive to exogenous benzoxazolinone in the important wheat pathogen Fusarium pseudograminearum.