First report of virulence to the septoria tritici blotch resistance gene <i>Stb16q</i> in the Irish <i>Zymoseptoria tritici</i> population

Kildea, Steven; Byrne, John J.; Cucak, Mladen; Hutton, Fiona

doi:10.5197/j.2044-0588.2020.041.013

Cited by 15 publications

(15 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Cellule was widely used in France, becoming the third most frequent cultivar grown (8% of the area under wheat in 2016), but its use then declined following a decrease in its resistance to STB. Indeed, STB symptoms were first observed on Cellule in 2015 in France (Romain Valade, ARVALIS‐Institut du Végétal, personal communication) and in 2019 in Ireland (Kildea et al, 2020), highlighting the beginning of a breakdown of Stb16q resistance.…”

Section: Introductionmentioning

confidence: 99%

Annual dynamics of Zymoseptoria tritici populations in wheat cultivar mixtures: A compromise between the efficacy and durability of a recently broken‐down resistance gene?

et al. 2021

View full text Add to dashboard Cite

Cultivar mixtures slow polycyclic epidemics but may also affect the evolution of pathogen populations by diversifying the selection pressures exerted by their plant hosts at field scale. We compared the dynamics of natural populations of the fungal pathogen Zymoseptoria tritici in pure stands and in three binary mixtures of wheat cultivars (one susceptible cultivar and one cultivar carrying the recently broken‐down Stb16q gene) over two annual field epidemics. We combined analyses of population “size” based on disease severity, and of population “composition” based on changes in the frequency of virulence against Stb16q in seedling assays with more than 3000 strains. Disease reductions were observed in mixtures late in the epidemic, at the whole‐canopy scale and on both cultivars, suggesting the existence of a reciprocal protective effect. The three cultivar proportions in the mixtures (0.25, 0.5, and 0.75) modulated the decrease in (a) the size of the pathogen population relative to the two pure stands, (b) the size of the virulent subpopulation, and (c) the frequency of virulence relative to the pure stand of the cultivar carrying Stb16q. Our findings suggest that optimal proportions may differ slightly between the three indicators considered. We argue potential trade‐offs that should be taken into account when deploying a resistance gene in cultivar mixtures: between the dual objectives “efficacy” and “durability,” and between the “size” and “frequency” of the virulent subpopulation. Based on current knowledge, it remains unclear whether virulent subpopulation size or frequency has the largest influence on interepidemic virulence transmission.

show abstract

Section: Introductionmentioning

confidence: 99%

Annual dynamics of Zymoseptoria tritici populations in wheat cultivar mixtures: A compromise between the efficacy and durability of a recently broken‐down resistance gene?

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Their act of resistance is supposed to be a gene-for-gene relationship as demonstrated in the Stb6 gene ( Brading et al, 2002 ). Both Stb6 and Stb16q were the source of resistance in European cultivars ( Ghaffary et al, 2012 ) but lost their effectiveness lately in certain geographical regions ( Saintenac et al, 2018 ; Kildea et al, 2020 ). These pathogen-specific major genes can confer resistance to the pathogen either at the seedling stage ( Stb7 , Stb9-15 , StbSm3 , StbWW , and TmStb1 ), adult stage ( Stb2 , Stb3 , Stb8 , and Stb17 ), or at all growth stages ( Stb1 , Stb4-6 , Stb16q , and Stb18 ) of the wheat plant ( Raman and Milgate, 2012 ; Brown et al, 2015 ).…”

Section: Introductionmentioning

confidence: 99%

Genome-Wide Association Analysis and Genomic Prediction for Adult-Plant Resistance to Septoria Tritici Blotch and Powdery Mildew in Winter Wheat

et al. 2021

View full text Add to dashboard Cite

Septoria tritici blotch (STB) caused by the fungal pathogen Zymoseptoria tritici and powdery mildew (PM) caused by Blumeria graminis f.sp tritici (Bgt) are among the forefront foliar diseases of wheat that lead to a significant loss of grain yield and quality. Resistance breeding aimed at developing varieties with inherent resistance to STB and PM diseases has been the most sustainable and environment-friendly approach. In this study, 175 winter wheat landraces and historical cultivars originated from the Nordic region were evaluated for adult-plant resistance (APR) to STB and PM in Denmark, Estonia, Lithuania, and Sweden. Genome-wide association study (GWAS) and genomic prediction (GP) were performed based on the adult-plant response to STB and PM in field conditions using 7,401 single-nucleotide polymorphism (SNP) markers generated by 20K SNP chip. Genotype-by-environment interaction was significant for both disease scores. GWAS detected stable and environment-specific quantitative trait locis (QTLs) on chromosomes 1A, 1B, 1D, 2B, 3B, 4A, 5A, 6A, and 6B for STB and 2A, 2D, 3A, 4B, 5A, 6B, 7A, and 7B for PM adult-plant disease resistance. GP accuracy was improved when assisted with QTL from GWAS as a fixed effect. The GWAS-assisted GP accuracy ranged within 0.53–0.75 and 0.36–0.83 for STB and PM, respectively, across the tested environments. This study highlights that landraces and historical cultivars are a valuable source of APR to STB and PM. Such germplasm could be used to identify and introgress novel resistance genes to modern breeding lines.

show abstract

“…More recently, a similar dramatic breakdown in STB resistance has occurred in Ireland, this time to the cv. Cellule, which has the novel resistance gene Stb16q (Kildea et al, 2020). As recently identified and characterized by Saintenac et al (2021), Stb16q conferred excellent levels of broad‐spectrum STB resistance.…”

Section: Introductionmentioning

confidence: 99%

Detection of virulence to septoria tritici blotch (STB) resistance conferred by the winter wheat cultivar Cougar in the Irish Zymoseptoria tritici population and potential implications for STB control

et al. 2021

View full text Add to dashboard Cite

Septoria tritici blotch (STB), caused by the ascomycete pathogenZymoseptoria tritici, is the most economically destructive disease of winter wheat throughout northern Europe (O'Driscoll et al., 2014).Following infection and a prolonged latent period, leaf necrosis is induced, with ensuing lesions that develop on the upper canopy during grain fill, leading to significant yield losses (Jørgensen et al., 2021). To prevent these losses, disease control programmes incorporating agronomic practices (e.g., delayed sowing), host resistance,

show abstract

First report of virulence to the septoria tritici blotch resistance gene Stb16q in the Irish Zymoseptoria tritici population

Cited by 15 publications

References 3 publications

Annual dynamics of Zymoseptoria tritici populations in wheat cultivar mixtures: A compromise between the efficacy and durability of a recently broken‐down resistance gene?

Annual dynamics of Zymoseptoria tritici populations in wheat cultivar mixtures: A compromise between the efficacy and durability of a recently broken‐down resistance gene?

Genome-Wide Association Analysis and Genomic Prediction for Adult-Plant Resistance to Septoria Tritici Blotch and Powdery Mildew in Winter Wheat

Detection of virulence to septoria tritici blotch (STB) resistance conferred by the winter wheat cultivar Cougar in the Irish Zymoseptoria tritici population and potential implications for STB control

Contact Info

Product

Resources

About