|Del Pilar Rojas, Maria|
Submitted to: Proceedings of National Scab Forum
Publication Type: Abstract Only
Publication Acceptance Date: 12/1/2007
Publication Date: 12/1/2007
Citation: Garvin, D.F., Del Pilar Rojas, M., Blankenheim, Z., Wennberg, K., Elakkad, A., Dill-Macky, R. 2007. FHB resistance of wheat lines near-isogenic for five different FHB resistance QTLs [abstract]. U.S. Wheat and Barley Scab Forum, December 1, 2007, Kansas City, Missouri. p. 226. Interpretive Summary:
Technical Abstract: To continue improving FHB resistance in hard red spring wheat (HRSW), it is imperative that new FHB resistance genes from wheat and its relatives be introduced into the HRSW germplasm base. In 2001, we initiated a program to use marker-assisted backcrossing to individually introgress five FHB resistance QTLs from diverse germplasm sources into three FHB-susceptible HRSW backgrounds (Norm, Wheaton, Apogee). The QTLs selected include two from Sumai 3 (Fhb1 and Qfhs.ifa-5AS) to serve as reference QTLs, one from the soft red winter wheat Freedom (reportedly on chromosome arm 2AS), one from the Brazilian wheat Frontana (chromosome arm 3AL), and one from wild emmer (Qfhs.ndsu-3A). The development of BC4-derived QTL near-isogenic lines (QTL-NILs) is now complete, and these lines have been subjected to comparative FHB resistance evaluations both in the field and greenhouse. Results of these evaluations involving all QTL-NILs in the Norm and Wheaton backgrounds have revealed the effects of the individual QTLs following attempted introgression into these two HRSW genetic backgrounds. Evidence has been found for enhanced FHB resistance in QTL-NILs harboring each of the QTLs introgressed, though this effect appears to be influenced both by genetic background and by the efficacy of the molecular markers used to introduce the QTLs. These QTL-NIL series provide new and useful germplasm for HRSW FHB resistance breeding efforts, and they are a useful resource for additional research on FHB resistance. For instance, we currently are using the lines to examine epistatic interactions between QTLs,and additional scientific uses may include exploring the molecular basis of host-pathogen interactions and the biological basis of differences between type I and type II resistance.