*4.4. Resistance Testing Aspects*

The pooling of inoculation dates makes it possible for treating a larger population in an inoculation and genotype di fferences can be identified better. The aggressiveness of the inocula for large scale tests should be checked before use. In this way, the use of inocula with standardized conidium concentration with low or no aggressiveness can be avoided. We need less inoculation times; the results will be more comparable. As resistance expression di ffers for di fferent isolates, the use of more isolates gives more reliable data on resistance level and its reliability, therefore representing a higher phenotyping quality where it is needed. All published reports stress the need for low DON contamination. As DON contamination does not correlate well in about 20% of the genotypes where DON overproduction and relative DON reduction [4] occurs, its testing should be included. Therefore, serial testing for DON in an advanced stadium of breeding is important to discard toxin overproducers and highly susceptible genotypes during breeding and variety registration tests [24].

**Author Contributions:** Conceptualization, A.M. and A.G.; methodology, A.M., A.G.; M.V., and B.T.; investigation, A.G., B.T., and M.V.; data curation, A.G. and A.M.; writing—original draft preparation, A.M. and A.G.; writing—review and editing, A.M. and A.G.; supervision, A.M.; project administration, B.T. and A.M. All authors have read and agreed to the published version of the manuscript.

**Funding:** MycoRed EU FP7 (KBBE-2007-2-5-05), GOP-1.1.1-11-2012-0159 projects (supported by Hungarian and EU sources) and TUDFO/51757/2019-ITM (2019-2023). The authors also acknowledge the kind help of Dr. Matyas Cserhati in correcting the English of the manuscript.

**Conflicts of Interest:** The authors declare no conflict of interest.
