Genetic Analysis of Adult Plant Resistance Genes to Stem Rust in Some Egyptian Bread Wheat Cultivars

Powdery mildew, caused by Blumeria graminis f. sp. tritici, is a widespread wheat disease in China. Identification of race-specific genes and adult plant resistance (APR) is of major importance in breeding for an efficient genetic control strategy. The objectives of this study were to (i) identify genes that confer seedling resistance to powdery mildew in Chinese bread wheat cultivars and introductions used by breeding programs in China and (ii) evaluate their APR in the field. The results showed that (i) 98 of 192 tested wheat cultivars and lines appear to have one or more resistance genes to powdery mildew; (ii) Pm8 and Pm4b are the most common resistance genes in Chinese wheat cultivars, whereas Pm8 and Pm3d are present most frequently in wheat cultivars introduced from CIMMYT, the United States, and European countries; (iii) genotypes carrying Pm1, Pm3e, Pm5, and Pm7 were susceptible, whereas those carrying Pm12, Pm16, and Pm20 were highly resistant to almost all isolates of B. graminis f. sp. tritici tested; and (iv) 22 genotypes expressed APR. Our data showed that the area under the disease progress curve, maximum disease severity on the penultimate leaf, and the disease index are good indicators of the degree of APR in the field. It may be a good choice to combine major resistance genes and APR genes in wheat breeding to obtain effective resistance to powdery mildew.

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Breeding triple rust resistant wheat cultivars for Australia using conventional and marker-assisted selection technologies

Australian Journal of Agricultural Research ◽

10.1071/ar07124 ◽

2007 ◽

Vol 58 (6) ◽

pp. 576 ◽

Cited By ~ 79

Author(s):

H. S. Bariana ◽

G. N. Brown ◽

U. K. Bansal ◽

H. Miah ◽

G. E. Standen ◽

...

Keyword(s):

Leaf Rust ◽

Resistance Genes ◽

Plant Resistance ◽

Stem Rust ◽

Marker Assisted Selection ◽

Rust Resistance ◽

Adult Plant Resistance ◽

Adult Plant ◽

Wheat Cultivars ◽

The University

Stem rust susceptibility of European wheats under Australian conditions posed a significant threat to wheat production for the early British settlers in Australia. The famous Australian wheat breeder, William Farrer, tackled the problem of stem rust susceptibility through breeding fast-maturing wheat cultivars. South-eastern Australia suffered a severe stem rust epidemic in 1973, which gave rise to a national approach to breeding for rust resistance. The National Wheat Rust Control Program was set up in 1975, modelled on the University of Sydney’s own rust resistance breeding program, at the University of Sydney Plant Breeding Institute, Castle Hill (now Cobbitty). Back-crossing of a range of sources of resistance provided genetically diverse germplasm for evaluation in various breeding programs. Current efforts are directed to building gene combinations through marker-assisted selection. Major genes for resistance to stem rust and leaf rust are being used in the back-crossing program of the ACRCP to create genetic diversity among Australian germplasm. Stripe rust and to a lesser extent leaf rust resistance in the Australian germplasm is largely based on combinations of adult plant resistance genes and our knowledge of their genomic locations has increased. Additional genes, other than Yr18/Lr34 and Yr29/Lr46, appeared to control adult plant resistance to both leaf rust and stripe rust. Two adult-plant stem rust resistance genes have also been identified. The development of selection technologies to achieve genotype-based selection of resistance gene combinations in the absence of bioassays has evolved in the last 5 years. Robust molecular markers are now available for several commercially important rust resistance genes. Marker-assisted selection for rust resistance is performed routinely in many wheat-breeding programs. Modified pedigree and limited back-cross methods have been used for breeding rust-resistant wheat cultivars in the University of Sydney wheat-breeding program. The single back-cross methodology has proved more successful in producing cultivars with combinations of adult plant resistance genes.

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Genetics of adult-plant leaf-rust resistance in four Indian and two Australian bread wheat cultivars

Genome ◽

10.1139/g94-061 ◽

1994 ◽

Vol 37 (3) ◽

pp. 436-439 ◽

Cited By ~ 1

Author(s):

F Shiwani ◽

R. G. Saini

Keyword(s):

Leaf Rust ◽

Bread Wheat ◽

Resistance Genes ◽

Plant Resistance ◽

Rust Resistance ◽

Adult Plant Resistance ◽

Leaf Rust Resistance ◽

Adult Plant ◽

Wheat Cultivars ◽

Partial Dominance

Genetic studies for leaf-rust resistance were conducted on four Indian (CPAN1235, HD2135, HP1209, and VL404) and two Australian (CSP44 and Oxley) bread wheat cultivars. The F2 and F3 plants from their crosses with each other and with susceptible cultivar Agra Local were tested against a mixture of pathotypes 77-1 and 77-2 (variants of race 77). Disease scores on F1's from resistant/susceptible parent crosses indicated partial dominance of resistance in these wheats. The six cultivars have two adult-plant resistance genes each. Their intercrosses revealed similar resistance gene(s) in CSP44 and Oxley, and CPAN1235 and HP1209. The six wheats appear to carry at least seven diverse leaf-rust resistance genes (temporarily named LrI to LrO) against pathotypes 77-1 + 77-2. Adult-plant resistance is additive and therefore the combinations of partially effective resistance genes identified in this study can provide higher levels of resistance. Because these genes are of hexaploid origin, they can be easily exploited in breeding programs. Furthermore, two or more resistance genes from the six wheat cultivars when combined with Lr34 are likely to impart durable resistance to leaf rust.Key words: adult-plant resistance, leaf-rust resistance, wheat, Puccinia recondita, Triticum aestivum.

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Assessment of Sources of Adult Plant Resistance Genes to Stem Rust in Ethiopian Durum Wheat Genotypes

Asian Journal of Applied Sciences ◽

10.3923/ajaps.2020.76.83 ◽

2020 ◽

Vol 13 (2) ◽

pp. 76-83

Author(s):

Abebech Desalegn A ◽

Mesfin Kebede Ges ◽

Gobeze Loha Yada

Keyword(s):

Durum Wheat ◽

Resistance Genes ◽

Plant Resistance ◽

Stem Rust ◽

Adult Plant Resistance ◽

Adult Plant ◽

Wheat Genotypes

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Adult Plant Resistance to Stem Rust and Molecular Marker Analysis of some Egyptian and Exotic Bread Wheat Genotypes

Journal of Plant Protection and Pathology ◽

10.21608/jppp.2018.44107 ◽

2018 ◽

Vol 9 (12) ◽

pp. 901-907

Author(s):

A. Shahin ◽

M. Hasan ◽

M. Abou-Zeid

Keyword(s):

Molecular Marker ◽

Bread Wheat ◽

Plant Resistance ◽

Stem Rust ◽

Adult Plant Resistance ◽

Adult Plant ◽

Wheat Genotypes ◽

Marker Analysis ◽

Molecular Marker Analysis

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Characterization of Ethiopian Wheat Germplasm for Resistance to Four Puccinia graminis f. sp. tritici Races Facilitated by Single-Race Nurseries

Plant Disease ◽

10.1094/pdis-07-18-1243-re ◽

2019 ◽

Vol 103 (9) ◽

pp. 2359-2366 ◽

Cited By ~ 6

Author(s):

Bekele Hundie ◽

Bedada Girma ◽

Zerihun Tadesse ◽

Erena Edae ◽

Pablo Olivera ◽

...

Keyword(s):

Durum Wheat ◽

Bread Wheat ◽

Plant Resistance ◽

Stem Rust ◽

Adult Plant Resistance ◽

Adult Plant ◽

Puccinia Graminis ◽

Wheat Lines ◽

Open Access Article

In Ethiopia, breeding rust resistant wheat cultivars is a priority for wheat production. A stem rust epidemic during 2013 to 2014 on previously resistant cultivar Digalu highlighted the need to determine the effectiveness of wheat lines to multiple races of Puccinia graminis f. sp. tritici in Ethiopia. During 2014 and 2015, we evaluated a total of 97 bread wheat and 14 durum wheat genotypes against four P. graminis f. sp. tritici races at the seedling stage and in single-race field nurseries. Resistance genes were postulated using molecular marker assays. Bread wheat lines were resistant to race JRCQC, the race most virulent to durum wheat. Lines with stem rust resistance gene Sr24 possessed the most effective resistance to the four races. Only three lines with adult plant resistance possessed resistance effective to the four races comparable with cultivars with Sr24. Although responses of the wheat lines across races were positively correlated, wheat lines were identified that possessed adult plant resistance to race TTKSK but were relatively susceptible to race TKTTF. This study demonstrated the importance of testing wheat lines for response to multiple races of the stem rust pathogen to determine if lines possessed non-race-specific resistance. [Formula: see text] Copyright © 2019 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

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