COLONIZATION OF WHEAT HEADS BY FUSARIUM HEAD BLIGHT ANTAGONIST CRYPTOCOCCUS FLAVESCENS OH 182.9 WHEN APPLIED ALONE OR IN COMBINATION WITH PROTHIOCONAZOLE AND THE TREATMENT EFFECT ON FHB DISEASE DEVELO

摘要

Quantify the colonization of infection court tissues of field-grown wheat by FHB biocontrol strain OH 182.9 in the presence or absence of field rates of prothioconazole and 2) determine FHB disease development for the same treatments applied in the colonization work. Research results to date from laboratories worldwide indicate that it is unlikely that any single control measure will reduce Fusarium head blight (FHB) of wheat to economically acceptable levels when conditions favor disease development. The use of yeast biological control agent Cyptococcus flavescens OH 182.9 (NRRL Y-30216) as part of an integrated management strategy against FHB is understudied yet has considerable potential for significantly contributing to the reduction of FHB anddeoxynivalenol (DON). We have isolated a prothioconazole-tolerant (PTCT) variant of OH 182.9 (OH 182.9 C3) that frequently exhibits enhanced biocontrol activity over its wild type progenitor strain (Schisler et al., 2009). This variant also is tolerant of tebuconazole. As part of an integrated control protocol, strain OH 182.9 could be applied to wheat and barley after flowering when fungicides are not approved for use.