New sources of resistance to Septoria tritici blotch in wheat seedlings

Leaf rust uredospore production and lesion size were measured on flag leaves of adult wheat plants in a glasshouse for different lesion densities. We estimated the spore weight produced per square centimeter of infected leaf, per lesion, and per unit of sporulating area. Three levels of fertilization were applied to the plants to obtain different nitrogen content for the inoculated leaves. In a fourth treatment, we evaluated the effect of Septoria tritici blotch on leaf rust uredospore production. The nitrogen and carbon content of the spores was unaffected or marginally affected by lesion density, host leaf nitrogen content, or the presence of Mycosphaerella graminicola on the same leaf. In leaves with a low-nitrogen content, spore production per lesion was reduced, but lesion size was unaffected. A threshold effect of leaf nitrogen content in spore production was however, evident, since production was similar in the medium- and high-fertilizer treatments. In leaves inoculated with M. graminicola and Puccinia triticina, the rust lesions were smaller and produced fewer spores. The relationships among rust lesion density, lesion size, and uredospore production were fitted to a model. We determined that the density effect on spore production resulted mainly from a reduction in lesion size, the spore production per unit of sporulating surface being largely independent of lesion density. These results are consistent with those obtained previously on wheat seedlings. The main difference was that the sporulation period lasted longer in adult leaves.

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Sources of resistance and susceptibility to Septoria tritici blotch of wheat

Molecular Plant Pathology ◽

10.1111/mpp.12482 ◽

2016 ◽

Vol 18 (2) ◽

pp. 276-292 ◽

Cited By ~ 15

Author(s):

Lia S. Arraiano ◽

James K. M. Brown

Keyword(s):

Septoria Tritici Blotch ◽

Septoria Tritici ◽

Sources Of Resistance

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Sources of resistance to septoria tritici blotch and implications for wheat breeding

Plant Pathology ◽

10.1111/j.1365-3059.2004.01052.x ◽

2004 ◽

Vol 53 (4) ◽

pp. 454-460 ◽

Cited By ~ 50

Author(s):

L. Chartrain ◽

P. A. Brading ◽

J. C. Makepeace ◽

J. K. M. Brown

Keyword(s):

Wheat Breeding ◽

Septoria Tritici Blotch ◽

Septoria Tritici ◽

Sources Of Resistance

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Resistance of Wheat Line Kavkaz-K4500 L.6.A.4 to Septoria Tritici Blotch Controlled by Isolate-Specific Resistance Genes

Phytopathology ◽

10.1094/phyto-95-0664 ◽

2005 ◽

Vol 95 (6) ◽

pp. 664-671 ◽

Cited By ~ 48

Author(s):

L. Chartrain ◽

S. T. Berry ◽

J. K. M. Brown

Keyword(s):

Resistance Genes ◽

Specific Resistance ◽

Field Resistance ◽

Field Conditions ◽

Septoria Tritici Blotch ◽

Septoria Tritici ◽

High Susceptibility ◽

Sources Of Resistance ◽

Wheat Improvement ◽

The Uk

The International Maize and Wheat Improvement Center (CIMMYT), Mexico, germplasm-derived wheat (Triticum aestivum) Kavkaz-K4500 L.6.A.4 (KK) is one of the major sources of resistance to Septoria tritici blotch (STB). KK is resistant to STB in field conditions in the UK even though a large majority of Mycosphaerella graminicola isolates are virulent to it. The genetics of the resistance of KK to four isolates of M. graminicola were investigated. KK has at least five isolate-specific resistance genes including Stb6 on chromosome 3A plus a second gene for resistance to isolate IPO323, two genes on chromosome 4A, both in the region where Stb7 is located with one designated as Stb12, and a gene designated Stb10 on chromosome 1D. Taken together, the widespread use of KK as a source of resistance to STB, its high resistance in field conditions, and its high susceptibility to M. graminicola isolates, which are virulent to all its resistance genes, suggest that high levels of field resistance to STB might be achieved by pyramiding several isolate-specific resistance genes.

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Behavior of Spanish durum wheat genotypes against Zymoseptoria tritici: resistance and susceptibility

Spanish Journal of Agricultural Research ◽

10.5424/sjar/2021193-17953 ◽

2021 ◽

Vol 19 (3) ◽

pp. e1002-e1002

Author(s):

Rafael Porras ◽

Keyword(s):

Durum Wheat ◽

Agronomic Traits ◽

Septoria Tritici Blotch ◽

Septoria Tritici ◽

Zymoseptoria Tritici ◽

Sources Of Resistance ◽

Breeding Lines ◽

Wheat Genotypes ◽

Commercial Cultivars ◽

Growth Chambers

Aim of study: Septoria tritici blotch (STB), caused by the fungus Zymoseptoria tritici, is one of the most important wheat diseases worldwide, affecting both bread and durum wheat. The lack of knowledge about the interaction of durum wheat with Z. tritici, together with limited resources of resistant durum wheat material, have both led to a rising threat for durum wheat cultivation, particularly in the Mediterranean Basin. In Spain, STB has increased its incidence in the last few years, leading to higher costs of fungicide applications to control the disease. Therefore, identification of new sources of resistance through wheat breeding stands out as an efficient method of facing STB. Area of study: The experimental study was conducted in growth chambers at the IFAPA facilities in Córdoba (Spain). Material and methods: The percentage of necrotic leaf area, the disease severity, and the pycnidium development through image analysis were evaluated from 48 durum wheat Spanish accessions (breeding lines and commercial cultivars) in growth chambers against an isolate of Z. tritici from Córdoba. Main results: Two breeding lines and six commercial cultivars showed resistant responses by limiting STB development through the leaf or its reproduction ability, while the other 40 accessions presented a susceptible response. Research highlights: Provided these resources of resistance in Spanish durum wheat genotypes, future breeding programs could be developed, incorporating both agronomic traits and resistance to STB.

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Identification of New Sources of Resistance to Tan Spot, Stagonospora Nodorum Blotch, and Septoria Tritici Blotch of Wheat

Crop Science ◽

10.2135/cropsci2005.12.0469 ◽

2006 ◽

Vol 46 (5) ◽

pp. 2047-2053 ◽

Cited By ~ 27

Author(s):

P. K. Singh ◽

M. Mergoum ◽

S. Ali ◽

T. B. Adhikari ◽

E. M. Elias ◽

...

Keyword(s):

Tan Spot ◽

Septoria Tritici Blotch ◽

Septoria Tritici ◽

Stagonospora Nodorum ◽

Sources Of Resistance ◽

Stagonospora Nodorum Blotch

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Genetic Analysis Using a Multi-Parent Wheat Population Identifies Novel Sources of Septoria Tritici Blotch Resistance

Genes ◽

10.3390/genes11080887 ◽

2020 ◽

Vol 11 (8) ◽

pp. 887

Author(s):

Adnan Riaz ◽

Petra KockAppelgren ◽

James Gerard Hehir ◽

Jie Kang ◽

Fergus Meade ◽

...

Keyword(s):

Natural Infection ◽

Resistance Breeding ◽

Triticum Aestivum L ◽

Septoria Tritici Blotch ◽

Septoria Tritici ◽

Zymoseptoria Tritici ◽

Sources Of Resistance ◽

Wheat Varieties ◽

Wheat Population ◽

Disease Management Strategy

Zymoseptoria tritici is the causative fungal pathogen of septoria tritici blotch (STB) disease of wheat (Triticum aestivum L.) that continuously threatens wheat crops in Ireland and throughout Europe. Under favorable conditions, STB can cause up to 50% yield losses if left untreated. STB is commonly controlled with fungicides; however, a combination of Z. tritici populations developing fungicide resistance and increased restrictions on fungicide use in the EU has led to farmers relying on fewer active substances. Consequently, this serves to drive the emergence of Z. tritici resistance against the remaining chemistries. In response, the use of resistant wheat varieties provides a more sustainable disease management strategy. However, the number of varieties offering an adequate level of resistance against STB is limited. Therefore, new sources of resistance or improved stacking of existing resistance loci are needed to develop varieties with superior agronomic performance. Here, we identified quantitative trait loci (QTL) for STB resistance in the eight-founder “NIAB Elite MAGIC” winter wheat population. The population was screened for STB response in the field under natural infection for three seasons from 2016 to 2018. Twenty-five QTL associated with STB resistance were identified in total. QTL either co-located with previously reported QTL or represent new loci underpinning STB resistance. The genomic regions identified and the linked genetic markers serve as useful resources for STB resistance breeding, supporting rapid selection of favorable alleles for the breeding of new wheat cultivars with improved STB resistance.

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Identification of New Sources of Resistance to Septoria Tritici Blotch Caused byZymoseptoria tritici

Journal of Phytopathology ◽

10.1111/jph.12282 ◽

2014 ◽

Vol 163 (2) ◽

pp. 84-90 ◽

Cited By ~ 3

Author(s):

Rahim Mehrabi ◽

Amin Makhdoomi ◽

Mohammad Jafar-Aghaie

Keyword(s):

Septoria Tritici Blotch ◽

Septoria Tritici ◽

Sources Of Resistance

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Inheritance in hexaploid wheat of Septoria tritici blotch resistance and other characteristics derived from Triticum tauschii

Australian Journal of Agricultural Research ◽

10.1071/ar9920433 ◽

1992 ◽

Vol 43 (3) ◽

pp. 433 ◽

Cited By ~ 13

Author(s):

CE May ◽

ES Lagudah

Keyword(s):

Dominant Gene ◽

Diploid Species ◽

Septoria Tritici Blotch ◽

Septoria Tritici ◽

Sources Of Resistance ◽

Genetic Traits ◽

Triticum Tauschii ◽

Phenotypic Differences ◽

Synthetic Hexaploid ◽

Synthetic Hexaploids

In an attempt to find new sources of resistance to the disease septoria tritici blotch (STB) of wheat, we have evaluated a worldwide collection of the diploid species Triticum tauschii for their reaction to infection by pycnidiospores of Mycosphaerella graminicola, the pathogen causing this disease. We have also screened a selection of synthetic hexaploid wheats, produced by hybridizing T. tauschii with tetraploid wheats, as well as the first and second generations of hybrids between some of these synthetics and commercial wheats. Almost 90% of the T. tauschii accessions and two-thirds of the synthetic hexaploids were resistant to STB. In the intercrosses with susceptible commercial wheats (e.g. Egret), the STB resistance was effectively transmitted as a single dominant gene, as indicated by a 3:l ratio of resistant: susceptible plants in F2 progenies. In crosses with the STB-resistant wheat, M1696, a 15:l ratio in F2 progenies indicated that the two resistance genes were different. F2 progenies involving the wheat cultivar Teal were more ambivalent. Other genetic traits also segregated in these plants although not all showed easily distinguishable phenotypic differences. Non-beneficial characters included genes for height, hybrid necrosis, grass clump dwarfism, tenacious glumes or threshability, speltoid head shape, and dark seed colour. Other genes controlled the more neutral characters coleoptile colour, hairy glumes and glume colour. Beneficial genes include resistance to septoria tritici blotch.

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QTL Mapping of Seedling and Adult Plant Resistance to Septoria Tritici Blotch in Winter Wheat cv. Mandub (Triticum aestivum L.)

Agronomy ◽

10.3390/agronomy11061108 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1108

Author(s):

Dominika Piaskowska ◽

Urszula Piechota ◽

Magdalena Radecka-Janusik ◽

Paweł Czembor

Keyword(s):

Mapping Population ◽

Triticum Aestivum L ◽

Seedling Stage ◽

Septoria Tritici Blotch ◽

Septoria Tritici ◽

Adult Plant ◽

Resistance Locus ◽

Phenotypic Variance ◽

Breeding Programs ◽

Plant Stage

Septoria tritici blotch (STB) is one of the most devastating foliar diseases of wheat worldwide. Host resistance is the most economical and safest method of controlling the disease, and information on resistance loci is crucial for effective breeding for resistance programs. In this study we used a mapping population consisting of 126 doubled-haploid lines developed from a cross between the resistant cultivar Mandub and the susceptible cultivar Begra. Three monopycnidiospore isolates of Z. tritici with diverse pathogenicity were used to test the mapping population and parents’ STB resistance at the seedling stage (under a controlled environment) and adult plant stage (polytunnel). For both types of environments, the percentage leaf area covered by necrosis (NEC) and pycnidia (PYC) was determined. A linkage map comprising 5899 DArTSNP and silicoDArT markers was used for the quantitative trait loci (QTL) analysis. The analysis showed five resistance loci on chromosomes 1B, 2B and 5B, four of which were derived from cv. Mandub. The location of QTL detected in our study on chromosomes 1B and 5B may suggest a possible identity or close linkage with Stb2/Stb11/StbWW and Stb1 loci, respectively. QStb.ihar-2B.4 and QStb.ihar-2B.5 detected on chromosome 2B do not co-localize with any known Stb genes. QStb.ihar-2B.4 seems to be a new resistance locus with a moderate effect (explaining 29.3% of NEC and 31.4% of PYC), conferring resistance at the seedling stage. The phenotypic variance explained by QTL detected in cv. Mandub ranged from 11.9% to 70.0%, thus proving that it is a good STB resistance source and can potentially be utilized in breeding programs.

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