Quantitative Trait Loci Analysis of Novel Fusarium Head Blight Resistance in Tokai 66

Abstract

Problem Statement: Identification of Quantitative Trait Loci (QTLs) in durable resistant genotype is important for marker-assisted breeding. The study was conducted to identify QTLs linked to FHB resistance in 'Tokai 66', a Japanese genotype. Approach: A cross was made between Tokai 66 and Jagalene and the single seed descend was used to advance the population. The F_2:4 and F_2:5 populations were evaluated by artificially inoculating disease in a mist-irrigated nursery in 2006 and 2007. Disease incidence, severity, FDK and DON content were evaluated in the 128 RILs. Map Manager QTX was used to prepare the linkage map and QTL Cartographer 2.0 was used to identify QTLs for FHB responses from the field data respectively. Results: Four QTLs for FHB responses were detected, of which one QTL each for severity and FDK were stable across two years and were located at the 5B and 3BSc, respectively. Both QTLs conferred resistance to FHB. Two unstable QTLs were detected at the 5B and 3D for FDK and DON content, respectively using the field environment. The 5B QTL for FDK contributed to susceptibility, whereas the 3D QTL for DON content contributed to resistance. Conclusion: The 5B QTL associated with resistance to severity and 3B QTL associated with resistance to FDK could be utilized by winter wheat breeding programs selection to enhance FHB resistance.