Further characterization of the scab resistance of ‘Frontana’ spring wheat and the relationships between resistance mechanisms

Abstract

ÔFrontanaÕ spring wheat exhibits resistance to Fusarium head blight (FHB), but it is not clear which genes confer resistance to initial infection or spread. This study assessed the FHB resistance of reciprocal backcross monosomic (RBCM) lines previously developed using Frontana and ÔChrisÕ. Six RBCM lines differing for Frontana and Chris disomic chromosomes 3A, 6A and 4D were evaluated to determine which chromosome prevents disease establishment or spread after either spray or single floret inoculation (SFI). Data were collected for FHB incidence, severity and spread. The RBCM line with Frontana chromosome 3A expressed the lowest FHB severity and incidence after spray inoculation and the lowest disease spread after SFI. This confirms a major role of Frontana chromosome 3A in resistance to FHB establishment and spread. Frontana chromosomes 6A and 4D also influence resistance but have less of an impact compared with 3A. Significant correlations between disease incidence and severity and between severity and visually Fusarium damaged kernels (VFDK) suggest that type I and type II resistant mechanisms do not function independently in Frontana. Therefore, the metrics used to quantify resistance are interrelated.

Minor Differences in Anther Extrusion Affect Resistance to Fusarium Head Blight in Wheat

“…Although FHB resistance in wheat could occur through various mechanisms, different types of resistant mechanisms may not always work independently (Yabwalo et al. ). AE is mainly associated with type I resistance, but can also mediate other important traits because AE is associated with grain deterioration and mycotoxin accumulation.…”

“…Resistance against FHB can be divided into resistance to initial infection (type I) and resistance to fungal spread within spikes (type II) (Schroeder and Christensen 1963); a type III resistance (resistance to mycotoxin accumulation) has also been proposed (Wang and Miller 1988). Although FHB resistance in wheat could occur through various mechanisms, different types of resistant mechanisms may not always work independently (Yabwalo et al 2011). AE is mainly associated with type I resistance, but can also mediate other important traits because AE is associated with grain deterioration and mycotoxin accumulation.…”

Molecular Mapping of Quantitative Trait Loci for Fusarium Head Blight Resistance in the Brazilian Spring Wheat Cultivar “Surpresa”

“…Frontana was a widely used FHB resistance source in the Brazilian, North American, and Canadian wheat breeding programs prior to the introduction of Asian germplasms ( Zhu et al, 2019 ). FHB resistance in Frontana has been characterized and validated across multiple studies and is primarily conferred by QTL on chromosome 3A ( Steiner et al, 2004 ; Mardi et al, 2006 ; Berzonsky et al, 2007 ; Yabwalo et al, 2011 ; Szabo-Hever et al, 2018 ). Besides the QTL on chromosome 3A, QTL from numerous chromosomes including 4A, 5A, 6A, 6B, 7A, 4D, some of which are coincident with QTL for PH and DA, contribute to FHB resistance in Frontana ( Steiner et al, 2004 ; Mardi et al, 2006 ; Berzonsky et al, 2007 ; Szabo-Hever et al, 2018 ).…”

“…Before Sumai3 was utilized in wheat breeding programs in the Americas, cultivar Frontana from Brazil was extensively used as the FHB resistance source ( Rudd et al, 2001 ; Zhu et al, 2019 ). Frontana primarily confers type I FHB resistance with some type II and type III FHB resistances ( Steiner et al, 2004 ; Yabwalo et al, 2011 ; Ágnes et al, 2014 ). Considering the shared ancestry and origin of Frontana and Surpresa, it would be interesting to decipher the genetic basis of FHB resistance in Surpresa.…”

Arms Race between the Host and Pathogen Associated with Fusarium Head Blight of Wheat

“…For example, Li et al (2019) finely localized the genetic locus of Qfhb.nau-2B in Nanda 2419 [ 75 ], and Jiang et al (2020) localized the FHB resistance QTL QFhb-5A in Yangmai 158 [ 55 ]. In addition, the fungus-resistant locus in different wheat resistance strains, such as the Swiss wheat variety Arina [ 76 ]; Ernie [ 77 ] and Truman [ 78 ] in the USA; Dream [ 79 ] in Germany; T. macha [ 80 ] in Maga, Frontana [ 81 ] in Brazil; Chok-wang [ 82 ] in Korea; and Nyubai [ 83 ] and SYN1, a synthetic species bred by the International Maize and Wheat Improvement Center (CIMMYT), all have been identified by constructing genetic populations RILs or DHLs. Furthermore, with the application of bioinformatics technology and the continuous improvement of genomic data, the methods of genome-wide association studies (GWAS) have been used to excavate resistant loci/QTLs or associated genes [ 84 ].…”