Relevance of Trichoderma afroharzianum as a corncob blight pathogen

Project Tricho-Maize

In 2018, a new pathogen was described for the first time on corn cobs in Germany, which led to massive infestations at several field trial sites in southern Germany. All cobs of the 20 maize varieties grown there were overgrown with the fungus. Based on microscopic and molecular biological investigations, the fungus occurring there was identified as Trichoderma afroharzianum. To date, the genus Trichoderma has never been conspicuous as a pathogen on maize cobs in Europe. The aim of the research project is to record the occurrence of Trichoderma species on maize cobs in a Europe-wide monitoring and to determine the damaging effect on maize, in particular the possible reduction in yield and quality. By means of inoculation trials in the greenhouse and field, the damage potential will first be determined. The data from the monitoring of the spread and from the inoculation trials on the damage potential will be incorporated into a risk analysis for this new maize pathogen, which will be carried out in cooperation with the JKI. In view of a required management of the disease, investigations on inoculum sources, dissemination routes and alternative hosts will continue. In this context, representative maize breeding material will be tested in field trials for the presence of resistance. Simultaneous inoculations on the corn cob with Trichoderma and Fusarium are also planned in order to investigate given interactions with regard to damage and mycotoxin contamination.