Studies conducted by the University of Manitoba are finding the 3-A DON chemotype to be much more aggressive than the previous 15-A DON chemotype.
Canadian Grain Commission mycologist Randy Clear says, since 1998 the prevalence of 3-A DON has increased from about five percent of infected wheat crops in western Canada to 40 to 50 percent.
http://www.farmscape.com/f2ShowScript.aspx?i=23210&q=More+Toxic+Fusarium+Graminearum+Chemotype+More+Prevalent+in+Western+Canada