Dissection and QTL Mapping of Component Traits of Resistance to Wheat Powdery Mildew at Early Infection Stage

AbstractIntrogressions of chromosomal segments from related species into wheat are important sources of resistance against fungal diseases. The durability and effectiveness of introgressed resistance genes upon agricultural deployment is highly variable - a phenomenon that remains poorly understood as the corresponding fungal avirulence genes are largely unknown. Until its breakdown, the Pm17 resistance gene introgressed from rye to wheat provided broad resistance against powdery mildew (Blumeria graminis). Here, we used QTL mapping to identify the corresponding wheat mildew avirulence effector AvrPm17. It is encoded by two paralogous genes that exhibit signatures of re-occurring gene conversion events and are members of a mildew sub-lineage specific effector cluster. Extensive haplovariant mining in wheat mildew and related sub-lineages identified several ancient virulent AvrPm17 variants that were present as standing genetic variation in wheat powdery mildew prior to the Pm17 introgression, thereby paving the way for the rapid breakdown of the Pm17 resistance. QTL mapping in mildew identified a second genetic component likely corresponding to an additional resistance gene present on the 1AL.1RS translocation carrying Pm17. This gene remained previously undetected due to suppressed recombination within the introgressed rye chromosomal segment. We conclude that the initial effectiveness of 1AL.1RS was based on simultaneous introgression of two genetically linked resistance genes. Our results demonstrate the relevance of pathogen-based genetic approaches to disentangle complex resistance loci in wheat. We propose that identification and monitoring of avirulence gene diversity in pathogen populations becomes an integral part of introgression breeding to ensure effective and durable resistance in wheat.Significance StatementDomesticated and wild wheat relatives provide an important source of new immune receptors for wheat resistance breeding against fungal pathogens. The durability of these resistance genes is variable and difficult to predict, yet it is crucial for effective resistance breeding. We identified a fungal effector protein recognised by an immune receptor introgressed from rye to wheat. We found that variants of the effector allowing the fungus to overcome the resistance are ancient. They were already present in the wheat powdery mildew gene pool before the introgression of the immune receptor and are therefore responsible for the rapid resistance breakdown. Our study demonstrates that the effort to identify new resistance genes should be accompanied by studies of avirulence genes on the pathogen side.

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Studies on the control effect of Bacillus subtilis on wheat powdery mildew

Pest Management Science ◽

10.1002/ps.6471 ◽

2021 ◽

Author(s):

Deshan Xie ◽

Xuewei Cai ◽

Chunping Yang ◽

Linjun Xie ◽

Guangwei Qin ◽

...

Keyword(s):

Bacillus Subtilis ◽

Powdery Mildew ◽

Control Effect ◽

Wheat Powdery Mildew

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Analysis of Anti-interference Ability of Hyperspectral Sensitive Features to Wheat Powdery Mildew

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/693/1/012124 ◽

2021 ◽

Vol 693 (1) ◽

pp. 012124

Author(s):

Jinling Zhao ◽

Guomin Chu ◽

Hao Yan ◽

Lei Hu ◽

Yongan Xue

Keyword(s):

Powdery Mildew ◽

Wheat Powdery Mildew

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The effect of phytoglobin overexpression on the plant proteome during nonhost response of barley (Hordeum vulgare) to wheat powdery mildew (Blumeria graminis f. sp. tritici)

Scientific Reports ◽

10.1038/s41598-020-65907-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

O. A. Andrzejczak ◽

C. K. Sørensen ◽

W.-Q. Wang ◽

S. Kovalchuk ◽

C. E. Hagensen ◽

...

Keyword(s):

Hordeum Vulgare ◽

Powdery Mildew ◽

Blumeria Graminis ◽

Wheat Powdery Mildew

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Fungicide sensitivity of populations of wheat powdery mildew (Erysiphe graminisf.sp.Tritici) in Central Europe in 1993

Pesticide Science ◽

10.1002/ps.2780430107 ◽

1995 ◽

Vol 43 (1) ◽

pp. 47-52 ◽

Cited By ~ 3

Author(s):

Miroslav Švec ◽

Marta Miklovičová ◽

Milan Sýkora ◽

Eduard Krippel

Keyword(s):

Powdery Mildew ◽

Central Europe ◽

Fungicide Sensitivity ◽

Wheat Powdery Mildew

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Changes in sterol composition with ontogeny of Blumeria graminis conidia

Canadian Journal of Botany ◽

10.1139/b00-106 ◽

2000 ◽

Vol 78 (10) ◽

pp. 1288-1293 ◽

Cited By ~ 2

Author(s):

Jérôme Muchembled ◽

Anissa Lounès-Hadj Sahraoui ◽

Anne Grandmougin-Ferjani ◽

Michel Sancholle

Keyword(s):

Powdery Mildew ◽

Plant Pathogen ◽

Total Sterol ◽

Sterol Composition ◽

Blumeria Graminis ◽

Erysiphe Graminis ◽

Qualitative And Quantitative ◽

Wheat Powdery Mildew

The total sterol composition of conidia of the obligate plant pathogen Blumeria (= Erysiphe) graminis f.sp. tritici has been analysed as a function of their ontogeny during sporulation. Two main classes of sterols were characterized: 24-ethylsterols (24-ethylcholesta-5,22-dienol, 24-ethylcholesterol, and Δ5-avenasterol) and 24-methylsterols (24-methylenecholesterol and episterol). Our results show that sterol composition is greatly modified during ontogeny of B. graminis conidia both at the qualitative and quantitative levels. In particular, 24-methylsterols, e.g., 24-methylenecholesterol and episterol, are the major sterols in old conidia whereas 24-ethylsterols, e.g., 24-ethylcholesta-5,22-dienol, 24-ethylcholesterol, and Δ5-avenasterol, are the main sterols in young conidia.Key words: Erysiphe, wheat powdery mildew, sterols, ontogeny.

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