Abstract
We compared the risk of reselecting melanin biosynthesis dehydratase inhibitor (MBI-D)-resistant Pyricularia oryzae isolates between two treatment programs, a nursery box application of diclocymet and a rotational program in which nursery boxes received a non-MBI-D fungicide application and then later, in the field, a foliar application of a diclocymet and ferimzone mixture. Both were effective against panicle blast. However, the latter prevented the reselection of MBI-D-resistant isolates more effectively than the former.