AGRONOMIC AND QUALITY CHARACTERISTICS OF WHEAT LINES WITH LEAF RUST RESISTANCE DERIVED FROM TRITICUM SPELTOIDES

Eleven lines of wheat (Triticum aestivum L.) carrying resistance to leaf rust (Puccinia recondita Rob. ex. Desm.) derived from five accessions of Triticum speltoides Tausch were grown in yield tests in 1977 and 1979. The grain was tested for quality characteristics in both years. Although the lines had been backcrossed four or five times to either Manitou or Neepawa, only four of the eleven showed any real promise of equalling their recurrent parent in agronomic and quality characteristics. Lines derived from the same accession of T. speltoides were surprisingly variable. The generally deleterious effects of the transferred chromatin are due either to genes linked to the genes for leaf rust resistance plus incomplete compensation by the speltoides chromosome segment for the aestivum segment it replaced, or to the effects of additional translocations that were not eliminated during backcrossing. A second cycle of homoeologous recombination is proposed as a way to eliminate some of the deleterious genes.

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The association of a gene for leaf rust resistance with the chromosome 7D suppressor of stem rust resistance in common wheat

Genome ◽

10.1139/g87-081 ◽

1987 ◽

Vol 29 (3) ◽

pp. 467-469 ◽

Cited By ~ 150

Author(s):

P. L. Dyck

Keyword(s):

Leaf Rust ◽

Common Wheat ◽

Stem Rust ◽

Rust Resistance ◽

Leaf Rust Resistance ◽

Triticum Aestivum L ◽

Suppressor Gene ◽

Stem Rust Resistance ◽

Recurrent Parent ◽

Cytogenetic Evidence

Backcross lines of gene LrT2 for resistance to leaf rust in the common wheat (Triticum aestivum L.) 'Thatcher' unexpectedly show improved resistance to stem rust compared with that of the recurrent parent. Genetic–cytogenetic evidence indicates that LrT2 is on chromosome 7D, which is known to carry the "suppressor" gene(s) that prevent the expression of stem rust resistance conferred by other genes in 'Canthatch'. Thus, LrT2 may be a nonsuppressing allele of the suppressor gene(s) or be closely linked to such an allele. LrT2 has been designated Lr34. Key words: Triticum, wheat, rust resistance.

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Virulence Polymorphism of Puccinia recondita f. sp. tritici and Effectiveness of Lr Genes for Leaf Rust Resistance of Wheat in Ukraine

Plant Disease ◽

10.1094/pd-90-0853 ◽

2006 ◽

Vol 90 (7) ◽

pp. 853-857 ◽

Cited By ~ 10

Author(s):

S. Elyasi-Gomari ◽

V. K. Panteleev

Keyword(s):

Leaf Rust ◽

Rust Resistance ◽

Mixed Race ◽

Leaf Rust Resistance ◽

Puccinia Recondita ◽

Forest Steppe ◽

Lr Genes ◽

Differential Cultivars ◽

Wheat Lines ◽

Field Plots

In 2002 and 2003, 1,300 isolates of Puccinia recondita f. sp. tritici were obtained from six commercial cultivars of wheat at three locations in the eastern forest-steppe region of Ukraine. All isolates were tested for virulence on an international set of eight differential cultivars. Seventeen known wheat leaf rust races and several new, unnamed races were identified. The most common races in each year were races 61, 149, and 192. In 2003, up to 20 isolates each of the seven most common leaf rust races plus 8 to 10 isolates of unnamed races were tested for virulence to 35 near-isogenic wheat lines with different single Lr genes for leaf rust resistance. Isolates were polymorphic for virulence on Lr1, Lr2a, Lr2b, Lr2c, Lr9, Lr19, Lr23, Lr26, and the combination Lr27 + Lr31. No isolates were found virulent on Lr24, Lr25, or Lr28, and few isolates were virulent on Lr9. Few isolates of known races but most isolates of the new, unnamed races were virulent on Lr19. The 35 Lr gene lines also were exposed to mixed-race inoculum in field plots to tests effectiveness of their resistance. Lines with Lr24, Lr25, and Lr28 suffered no leaf rust damage in the field, and lines with Lr9, Lr18, Lr35, Lr36, and the combination Lr27 + Lr31 showed less than 10% severity.

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INHERITANCE OF LEAF RUST RESISTANCE IN WHEAT CULTIVARS RAFAELA AND EAP 26127 AND CHROMOSOME LOCATION.OF GENE Lr17

Canadian Journal of Genetics and Cytology ◽

10.1139/g77-038 ◽

1977 ◽

Vol 19 (2) ◽

pp. 355-358 ◽

Cited By ~ 9

Author(s):

P. L. Dyck ◽

E. R. Kerber

Keyword(s):

Triticum Aestivum ◽

Leaf Rust ◽

Rust Resistance ◽

Leaf Rust Resistance ◽

Triticum Aestivum L ◽

Puccinia Recondita ◽

Wheat Cultivars ◽

Seedling Resistance

The inheritance of seedling resistance to leaf rust (Puccinia recondita) was studied in wheat (Triticum aestivum L.) cultivars Rafaela and EAP 26127. Rafaela has genes Lr14b and Lr17 while EAP 26127 has Lr17. Lr17 was located on chromosome 2A, possibly the short arm, and was independent of Lr11.

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Selection of Puccinia recondita f.sp. tritici virulence phenotypes in three multilines of Thatcher wheat lines near isogenic for leaf rust resistance genes

Canadian Journal of Botany ◽

10.1139/b95-117 ◽

1995 ◽

Vol 73 (7) ◽

pp. 1081-1088 ◽

Cited By ~ 9

Author(s):

J. A. Kolmer

Keyword(s):

Leaf Rust ◽

Resistance Genes ◽

Rust Resistance ◽

Leaf Rust Resistance ◽

Puccinia Recondita ◽

Near Isogenic Lines ◽

Isogenic Lines ◽

Wheat Lines ◽

Rust Resistance Genes ◽

Leaf Rust Resistance Genes

A heterogeneous population of Puccinia recondita f.sp. tritici developed from randomly mated pycnial infections on Thalictrum speciosissimum was selected for 12 generations on three multilines composed of Thatcher wheat lines near-isogenic for leaf rust resistance genes. Multiline 1 was composed of 20% each of lines near-isogenic for resistance genes Lr2a, Lr3ka, Lr11, Lr17, and Lr24. Multiline 2 was composed of equal proportions each of Thatcher and the five near-isogenic lines in multiline 1. Multiline 3 was composed of 50% Thatcher and 10% each of the five near-isogenic lines. Diversity of virulence phenotypes as measured by the Shannon index declined most in the population selected on multiline 1. Phenotypes of P. r. tritici with virulence to three of the five resistance genes in the multilines were the predominant isolates in all three populations after 12 generations of selection. Frequency of phenotypes with virulence to resistance genes Lr2a and Lr11 significantly increased in all three populations. Virulence to Lr11 significantly increased in the multiline 3 population, and virulence to Lr24 increased in populations from multilines 2 and 3. Frequency of phenotypes with virulence to Lr3ka did not significantly change in any of the populations. Virulence phenotypes with an intermediate number of virulences appeared to have fitness advantage relative to other isolates on the three host multilines. These results indicate that use of wheat multilines may not necessarily stabilize selection for virulence complexity in P. r. tritici populations. Key words: mixtures, Triticum aestivum, wheat leaf rust.

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Map-Based Cloning of Leaf Rust Resistance Gene Lr21 From the Large and Polyploid Genome of Bread Wheat

Genetics ◽

10.1093/genetics/164.2.655 ◽

2003 ◽

Vol 164 (2) ◽

pp. 655-664 ◽

Cited By ~ 3

Author(s):

Li Huang ◽

Steven A Brooks ◽

Wanlong Li ◽

John P Fellers ◽

Harold N Trick ◽

...

Keyword(s):

Amino Acid ◽

Leaf Rust ◽

Resistance Gene ◽

Bread Wheat ◽

Rust Resistance ◽

Agronomic Traits ◽

Leaf Rust Resistance ◽

Triticum Aestivum L ◽

Rust Resistance Gene ◽

Leaf Rust Resistance Gene

Abstract We report the map-based cloning of the leaf rust resistance gene Lr21, previously mapped to a generich region at the distal end of chromosome arm 1DS of bread wheat (Triticum aestivum L.). Molecular cloning of Lr21 was facilitated by diploid/polyploid shuttle mapping strategy. Cloning of Lr21 was confirmed by genetic transformation and by a stably inherited resistance phenotype in transgenic plants. Lr21 spans 4318 bp and encodes a 1080-amino-acid protein containing a conserved nucleotide-binding site (NBS) domain, 13 imperfect leucine-rich repeats (LRRs), and a unique 151-amino-acid sequence missing from known NBS-LRR proteins at the N terminus. Fine-structure genetic analysis at the Lr21 locus detected a noncrossover (recombination without exchange of flanking markers) within a 1415-bp region resulting from either a gene conversion tract of at least 191 bp or a double crossover. The successful map-based cloning approach as demonstrated here now opens the door for cloning of many crop-specific agronomic traits located in the gene-rich regions of bread wheat.

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