Author
![]() |
PETERSEN, S - North Carolina State University |
![]() |
LYERLY, J - North Carolina State University |
![]() |
MALONEY, P - North Carolina State University |
![]() |
NAVARRO, R - North Carolina State University |
![]() |
Cowger, Christina |
![]() |
Brown-Guedira, Gina |
![]() |
Costa, Jose |
![]() |
GRIFFEY, C - Virginia Polytechnic Institution & State University |
![]() |
MURPHY, J - North Carolina State University |
Submitted to: National Fusarium Head Blight Forum
Publication Type: Proceedings Publication Acceptance Date: 10/20/2014 Publication Date: N/A Citation: N/A Interpretive Summary: Breeding for resistance to Fusarium Head Blight is of major importance as the disease can have serious negative impacts on wheat production in warm and humid regions of the world, including the state of North Carolina. The importance of finding native sources of resistance in U.S. soft red winter wheat lines has been emphasized in recent years. The North Carolina cultivar NC-Neuse is a moderately FHB resistant soft red winter wheat, released in 2003. A population of 170 wheat lines derived from a cross between ‘NC Neuse’ and the FHB susceptible line ‘AGS 2000’ was evaluated for FHB resistance over several years. Suitable data for at least some FHB traits were collected from seven environments. Several traits related to resistance to FHB were evaluated, including accumulation of the mycotoxin deoxynivalenol (DON). At all QTL except one on chromosome 5B, NC-Neuse contributed resistance. Technical Abstract: Breeding for resistance to Fusarium Head Blight is of major importance as the disease can have serious negative impacts on wheat production in warm and humid regions of the world, including the state of North Carolina. Fusarium Head Blight can cause significant grain yield reduction, but also severely affect the grain quality due to accumulation of mycotoxins produced by the pathogen. The importance of finding native sources of resistance in U.S. soft red winter wheat lines has been emphasized in recent years. The North Carolina cultivar NC-Neuse is a moderately FHB resistant soft red winter wheat, released in 2003. A population of 170 random F5 -derived recombinant inbred lines derived from a cross between ‘NCNeuse’ and the FHB susceptible line ‘AGS 2000’ was evaluated for FHB resistance over several years and locations. Suitable data for at least some FHB traits were collected from a total of seven environments (2-3 reps/env). These included Kinston, NC in 2011, 2012, 2013, and 2014; Salisbury, MD in 2012; and Lake Wheeler, NC in 2013 and 2014. The FHB related traits evaluated were disease incidence (INC), severity (SEV), Fusarium damaged kernels (FDK), and accumulation of the mycotoxin deoxynivalenol (DON). Least squares means (lsmeans) were calculated from the phenotypic data within and across environments. In environments where heading date (HD) was significant, this was used as covariate in the data analysis and calculations of lsmeans. A linkage map containing a total of 1839 polymorphic SSR, DArT and SNP markers across 27 linkage groups was developed and utilized for mapping of QTL in this population. QTL analysis was conducted using Composite Interval Mapping (CIM) and then Multiple Interval Mapping (MIM) with WinQTLCart 2.5. The critical LOD value to declare QTL significance was 3.0, based on 1000 permutations. We identified QTL associated with FHB resistance (from several environments and/or several resistance traits) on chromosomes 1A, 1B, 2A, 4A, 5B, and 6A. Their LOD scores ranged from 3.0 to 5.4 with effects between 5.5-11.5%. At all QTL except the one on chromosome 5B, the NC-Neuse allele contributed resistance. The QTL on 5B (co-localized with the Vrn-B1 locus) showed up only in 2012 environments, probably due to an usually mild winter. QTL for HD and plant height were mapped to chromosomes 2B, 4A, 5B, 6A, and 7D. The resistance QTL on chromosomes 4A and 6A did not colocalize with QTL controlling HD and/or plant height. In the coming months, markers associated with the identified resistance QTL will be run on a broader set of wheat lines to test their usefulness and to test frequencies of resistance alleles. |