Why some pathogens don't develop resistance to Qo Inhibitors:

Derek Hollomon: Are some diseases unlikely to develop QoI resistance? Pest Management Science 63; 217-218
Helge Sierotzki *, Regula Frey, Jürg Wullschleger, Simona Palermo, Serge Karlin, Jeremy Godwin, Ulrich Gisi: Cytochrome b gene sequence and structure of Pyrenophora teres and P. tritici-repentis and implications for QoI resistance. Pest Management Science 63; 225-233