As the tests were made in both research institutes, it is reasonable that they share the IP for the finding. 24-24 genotypes selected from the population CM 82036/Remus were used for the test having 2 QTLs 3B and 5A, 3B and 5 A separately and again a group without known QTLs. The 3B QTLs is effective against spreading, called also resistance component 2, 5A is effective against invasion, normally measured by the ratio of infected heads, called also resistance component 1.
These two QTLs are the two, which have the strongest effect on FHB resistance among QTLs identified until now. All other QTLs have medium or small effect. For this reason it was an important question, what is the function of these QTLs following field inoculation.
For this a two sites, two plot-replicated trial was used, where each plot replicate was treated by eight different Fusarium isolate. Following inoculation FHB rating on the field, FDK, toxin (DON) contamination, 1000 grain mass, seed No./head, test weight, yield response, DNA and ergosterol content was measured to see the scope of the QTLs. The most important lessen is that the group means for lines carrying 5A and 3B QTLs gave very similar performance with no or slight difference, even for toxin contamination.
The group having both QTLs gave significantly better effect, very high resistance as a synergetic effect of the two differing effect QTLs. This proved us, and all breeders that 3B is alone not effective enough to secure high level of resistance and the same is valid for the 5A QTL. For this reason an effective strategy is only that utilizes both QTL types in one plant. We think, this is the most important message of the test. Further, there was no difference for the different Fusarium spp. used. This is the first clear prove that individual QTLs are species non specific. This is again a highly important message for the breeders.
Additionally the QTL effect was strongest for FHB, FDK and DON (or for F. avenaceum moniliformin), the other traits were less influenced and difference between 3B+5A was not always different from the individual 3B and 5B effect. The last message was that the large effect QTLs were evenly identified in both institutes that worked with different methods in different environments. This means that these QTLs can be worked with under very different environments and conditions, which is again good news for the breeders.