Physiologic races of wheat stem rust in Canada from 1919 to 1969

1971 ◽  
Vol 49 (9) ◽  
pp. 1575-1588 ◽  
Author(s):  
G. J. Green
Keyword(s):  
Resistance Genes ◽  
Stem Rust ◽  
Single Gene ◽  
Effective Resistance ◽  
Stabilizing Selection ◽  
New Combinations ◽  
Wheat Stem Rust ◽  
The Past ◽  
Physiologic Races ◽  
New System

The races of wheat stem rust found in Canada and identified by the "standard" and "formula" methods are described. Seven races or race groups made up 90.8% of the isolates. In 1964 a new system of race identification was introduced. It makes use of virulence formulas consisting of the numbers of effective resistance genes in the numerator and ineffective genes in the denominator. Resistance genes Sr6, Sr8, Sr9a, Sr9b, and Sr13 confer resistance to most isolates obtained since 1964, but no single gene confers resistance to all isolates. Experience shows that 250 isolates per year are sufficient to establish the trends of prevalence of the main races. The detection of rare, new combinations of virulence requires screening varieties carrying combinations of resistance genes. The main races in the past 50 years have been 56 and 15B. Race 56 is uniform with a single subrace but 15B is variable with many subraces. There is no evidence that unnecessary virulence is harmful or that "stabilizing selection" is operative in Canada, nor is there evidence that virulence on resistance genes Sr6 and Sr11 is harmful to the rust.

THE INHERITANCE OF PATHOGENICITY IN RACES 111 AND 29 OF WHEAT STEM RUST

1969 ◽  
Vol 11 (2) ◽  
pp. 266-274 ◽  
Author(s):  
K. N. Kao ◽  
D. R. Knott
Keyword(s):  
Stem Rust ◽  
Rust Resistance ◽  
Single Gene ◽  
Stem Rust Resistance ◽  
Wheat Stem Rust ◽  
Complementary Genes

The inheritance of pathogenicity in wheat stem rust was studied in selfed cultures of races 29 and 111, F1 and F2 cultures of a cross between the two races and cultures from a backcross to race 29. The various cultures were tested on Marquis and Prelude and on a series of lines of these varieties carrying single genes for stem rust resistance. Virulence on Sr 5, Sr 6, Sr 8, Sr 9a, Sr 14 and a gene in Marquis was recessive and in each case there was a single gene for virulence corresponding to each gene for resistance. Virulence on Sr 1 was possibly controlled by two dominant complementary genes. There appeared to be two alleles for virulence on Prelude, one dominant and one recessive.

scholarly journals Stem Rust Resistance in A-Genome Diploid Relatives of Wheat

Plant Disease ◽  
2011 ◽  
Vol 95 (8) ◽  
pp. 941-944 ◽  
Author(s):  
M. N. Rouse ◽  
Y. Jin
Keyword(s):  
Resistance Genes ◽  
Stem Rust ◽  
Rust Resistance ◽  
Infection Type ◽  
Genetic Resistance ◽  
Wheat Breeding ◽  
Stem Rust Resistance ◽  
Wheat Stem Rust ◽  
A Genome ◽  
Stem Rust Resistance Genes

Wheat stem rust, caused by Puccinia graminis f. sp. tritici, has been effectively controlled through the use of genetic resistance. P. graminis f. sp. tritici race TTKSK (Ug99) possesses virulence to many resistance genes that have been used in wheat breeding worldwide. One strategy to aid breeders in developing resistant cultivars is to utilize resistance genes transferred from wild relatives to wheat. Stem rust resistance genes have previously been introgressed from Triticum monococcum to wheat. In order to identify additional resistance genes, we screened 1,061 accessions of T. monococcum and 205 accessions of T. urartu against race TTKSK and four additional P. graminis f. sp. tritici races: TTTTF, TRTTF, QFCSC, and MCCFC. A high frequency of the accessions (78.7% of T. monococcum and 93.0% of T. urartu) were resistant to P. graminis f. sp. tritici race TTKSK, with infection types ranging from 0 to 2+. Among these resistant accessions, 55 T. monococcum accessions (6.4% of the total) were also resistant to the other four races. Associations of resistance in T. monococcum germplasm to different races indicated the presence of genes conferring resistance to multiple races. Comparing the observed infection type patterns to the expected patterns of known genes indicated that previously uncharacterized genes for resistance to race TTKSK exist in both T. monococcum and T. urartu.

scholarly journals Molecular Marker Based Design for Breeding Wheat Lines with Multiple Resistance and Superior Quality

Plant Disease ◽  
2020 ◽  
Vol 104 (10) ◽  
pp. 2658-2664
Author(s):  
Tao Liu ◽  
George Fedak ◽  
Lianquan Zhang ◽  
Rangrang Zhou ◽  
Dawn Chi ◽  
...  
Keyword(s):  
Stripe Rust ◽  
Resistance Genes ◽  
High Resistance ◽  
Stem Rust ◽  
Rust Resistance ◽  
Stripe Rust Resistance ◽  
Multiple Resistance ◽  
Wheat Stem Rust ◽  
Wheat Production ◽  
Rust Resistance Genes

There has not been a major wheat stem rust epidemic worldwide since the 1970s, but the emergence of race TTKSK of Puccinia graminis f. sp. tritici in 1998 presented a great threat to the world wheat production. Single disease-resistance genes are usually effective for only several years before the pathogen changes genetically to overcome the resistance. Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst) is one of the most common and persistent wheat diseases worldwide. The development of varieties with multiple resistance is the most economical and effective strategy for preventing stripe rust and stem rust, the two main rust diseases constraining wheat production. Plateau 448 has been widely used in the spring wheat growing region in northwest China, but it has become susceptible to stripe rust and is susceptible to TTKSK. To produce more durable resistance to race TTKSK as well as to stripe rust, four stem rust resistance genes (Sr33, Sr36, Sr-Cad, and Sr43) and three stripe rust resistance genes (Yr5, Yr18, and Yr26) were simultaneously introgressed into Plateau 448 to improve its stem rust (Ug99) and stripe rust resistance using a marker-assisted backcrossing strategy combined with phenotypic selection. We obtained 131 BC1F5 lines that pyramided two to four Ug99 resistance genes and one to two Pst resistance genes simultaneously. Thirteen of these lines were selected for their TTKSK resistance, and all of them exhibited near immunity or high resistance to TTKSK. Among the 131 pyramided lines, 95 showed high resistance to mixed Pst races. Nine lines exhibited not only high resistance to TTKSK and Pst but also better agronomic traits and high-molecular-weight glutenin subunit compositions than Plateau 448.

scholarly journals Mapping and characterization of wheat stem rust resistance genes SrTm5 and Sr60 from Triticum monococcum

2017 ◽  
Vol 131 (3) ◽  
pp. 625-635 ◽  
Author(s):  
Shisheng Chen ◽  
Yan Guo ◽  
Jordan Briggs ◽  
Felix Dubach ◽  
Shiaoman Chao ◽  
...  
Keyword(s):  
Resistance Genes ◽  
Stem Rust ◽  
Rust Resistance ◽  
Stem Rust Resistance ◽  
Triticum Monococcum ◽  
Wheat Stem Rust ◽  
Stem Rust Resistance Genes ◽  
Rust Resistance Genes

scholarly journals Identification of stem rust resistance genes in wheat cultivars in China using molecular markers

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4882 ◽  
Author(s):  
Xiaofeng Xu ◽  
Depeng Yuan ◽  
Dandan Li ◽  
Yue Gao ◽  
Ziyuan Wang ◽  
...  
Keyword(s):  
Molecular Markers ◽  
Resistance Genes ◽  
Stem Rust ◽  
Rust Resistance ◽  
Genetic Material ◽  
Stem Rust Resistance ◽  
Wheat Cultivars ◽  
Wheat Stem Rust ◽  
Stem Rust Resistance Genes ◽  
Rust Resistance Genes

Wheat stem rust caused by Puccinia graminis f. sp. tritici Eriks. & E. Henn. (Pgt), is a major disease that has been effectively controlled using resistance genes. The appearance and spread of Pgt races such as Ug99, TKTTF, and TTTTF, which are virulent to most stem rust-resistant genes currently deployed in wheat breeding programs, renewed the interest in breeding cultivars resistant to wheat stem rust. It is therefore important to investigate the levels of resistance or vulnerability of wheat cultivars to Pgt races. Resistance to Pgt races 21C3CTHQM, 34MKGQM, and 34C3RTGQM was evaluated in 136 Chinese wheat cultivars at the seedling stage. A total of 124 cultivars (91.2%) were resistant to the three races. Resistance genes Sr2, Sr24, Sr25, Sr26, Sr31, and Sr38 were analyzed using molecular markers closely linked to them, and 63 of the 136 wheat cultivars carried at least one of these genes: 21, 25, and 28 wheat cultivars likely carried Sr2, Sr31, and Sr38, respectively. Cultivars “Kehan 3” and “Jimai 22” likely carried Sr25. None of the cultivars carried Sr24 or Sr26. These cultivars with known stem rust resistance genes provide valuable genetic material for breeding resistant wheat cultivars.

RESISTANCE IN WHEAT TO FORMAE SPECIALES TRITICI AND SECALIS OF PUCCINIA GRAMINIS

1971 ◽  
Vol 13 (1) ◽  
pp. 119-127 ◽  
Author(s):  
A. K. Sanghi ◽  
N. H. Luig
Keyword(s):  
Stem Rust ◽  
Virulence Genes ◽  
Somatic Hybrids ◽  
Puccinia Graminis ◽  
New Combinations ◽  
Wheat Cultivars ◽  
Wheat Stem Rust ◽  
Formae Speciales ◽  
Two Hybrid

Nine genes conditioning resistance to cultures of P. graminis tritici (possessing unusual genes for avirulence), P. graminis secalis, and sexual or somatic hybrids between these formae speciales were found in the wheat cultivars Mentana and Yalta. In Mentana, Sr8 operated against all six cultures utilized; but in Yalta, Sr11 conditioned resistance to only two hybrid cultures. In addition, four other genes in Mentana and three genes in Yalta operated against the cultures.The present study indicates that hybridization between wheat stem rust and rye stem rust can be important in producing new combinations of virulence genes which can attack known genes for resistance in wheat. The implications of such hybridization in relation to the transference to wheat of resistance in rye to P. graminis tritici are discussed.

THE EFFECT OF DDT ON THE STEM RUST REACTION OF KHAPLI WHEAT

1946 ◽  
Vol 24c (2) ◽  
pp. 23-25 ◽  
Author(s):  
T. Johnson
Keyword(s):  
North America ◽  
Stem Rust ◽  
Wheat Stem Rust ◽  
Physiologic Races

Seedling leaves of Khapli wheat—a variety highly resistant to physiologic races of wheat stem rust prevalent in North America—became susceptible to stem rust a few days after they had been sprayed with DDT (1 oz. in 5 gal. water). The response to DDT was highly specific, as only one other of the resistant wheats tested (Arnautka) showed any indication of susceptibility consequent on spraying. Specificity of response was also indicated by the development of marked chlorosis on leaves of some varieties, whereas other varieties remained unaffected.

Stabilizing selection in Puccinia graminis tritici in Canada

1976 ◽  
Vol 54 (19) ◽  
pp. 2204-2214 ◽  
Author(s):  
Mishael Oichoe Osoro ◽  
G. J. Green
Keyword(s):  
Field Experiment ◽  
Stem Rust ◽  
Virulence Genes ◽  
Spore Production ◽  
Stabilizing Selection ◽  
Puccinia Graminis ◽  
Wheat Stem Rust ◽  
Wheat Varieties ◽  
Competitive Abilities ◽  
Field Plots

Experiments were designed to show whether or not virulence genes reduce fitness and bring about stabilizing selection. The competitive abilities of seven related races of Puccinia graminis f. sp. tritici were studied on seedlings of three to five susceptible wheat varieties by growing mixtures of the races in greenhouses, growth cabinets, and field plots. In experiments in which simple races with few virulence genes were mixed with complex races with one, two, or three extra virulence genes, the complex races predominated after 4 to 10 generations in five of the six mixtures, and the simple race predominated in one mixture. A complex race predominated over simple races in the field experiment. It was concluded that virulence genes did not impair the fitness of the wheat stem rust races studied.In one race mixture studied in growth cabinets the complex race predominated at 25 °C, and the simple race, at 15 °C. Temperature did not differentially influence the competitive abilities of the races in three other mixtures.Incubation periods for all races were shorter at higher temperatures, but races C18(15B-1L) and C33(15B-1L) developed faster than races C9(15B-1L), C37(15), C38(15B-1L), C42(15), and C49(15) at all temperatures. In addition, races C18(15B-1L) and C33(15B-1L) produced more urediospores per pustule than races C9(15B-1L), C37(15), and C49(15). The differences in incubation period and spore production are considered to be the most important factors studied and they could cause the differences in aggressiveness of the seven races.

scholarly journals Mapping and Characterization of a Wheat Stem Rust Resistance Gene in Durum Wheat “Kronos”

2021 ◽  
Vol 12 ◽  
Author(s):  
Hongna Li ◽  
Lei Hua ◽  
Matthew N. Rouse ◽  
Tianya Li ◽  
Shuyong Pang ◽  
...  
Keyword(s):  
Durum Wheat ◽  
Resistance Genes ◽  
Stem Rust ◽  
Rust Resistance ◽  
Wheat Variety ◽  
Wheat Breeding ◽  
Stem Rust Resistance ◽  
Wheat Stem Rust ◽  
Seedling Resistance ◽  
Or Gene

Wheat stem (or black) rust is one of the most devastating fungal diseases, threatening global wheat production. Identification, mapping, and deployment of effective resistance genes are critical to addressing this challenge. In this study, we mapped and characterized one stem rust resistance (Sr) gene from the tetraploid durum wheat variety Kronos (temporary designation SrKN). This gene was mapped on the long arm of chromosome 2B and confers resistance to multiple virulent Pgt races, such as TRTTF and BCCBC. Using a large mapping population (3,366 gametes), we mapped SrKN within a 0.29 cM region flanked by the sequenced-based markers pku4856F2R2 and pku4917F3R3, which corresponds to 5.6- and 7.2-Mb regions in the Svevo and Chinese Spring reference genomes, respectively. Both regions include a cluster of nucleotide binding leucine-repeat (NLR) genes that likely includes the candidate gene. An allelism test failed to detect recombination between SrKN and the previously mapped Sr9e gene. This result, together with the similar seedling resistance responses and resistance profiles, suggested that SrKN and Sr9e may represent the same gene. We introgressed SrKN into common wheat and developed completely linked markers to accelerate its deployment in the wheat breeding programs. SrKN can be a valuable component of transgenic cassettes or gene pyramids that includes multiple resistance genes to control this devastating disease.

scholarly journals Evaluation and identification of stem rust resistance genesSr2,Sr24,Sr25,Sr26,Sr31andSr38in wheat lines from Gansu Province in China

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e4146 ◽  
Author(s):  
Xiao Feng Xu ◽  
Dan Dan Li ◽  
Yang Liu ◽  
Yue Gao ◽  
Zi Yuan Wang ◽  
...  
Keyword(s):  
Resistance Genes ◽  
Stem Rust ◽  
Rust Resistance ◽  
Stem Rust Resistance ◽  
Gansu Province ◽  
Wheat Cultivars ◽  
Wheat Stem Rust ◽  
Stem Rust Resistance Genes ◽  
Wheat Lines ◽  
Rust Resistance Genes

Wheat stem rust, caused byPuccinia granimisf. sp.tritici, severely affects wheat production, but it has been effectively controlled in China since the 1970s. However, the appearance and spread of wheat stem rust races Ug99 (TTKSK, virulence toSr31), TKTTF (virulence toSrTmp) and TTTTF (virulence to the cultivars carryingSr9eandSr13) have received attention. It is important to clarify the effectiveness of resistance genes in a timely manner, especially for the purpose of using new resistance genes in wheat cultivars for durable-resistance. However, little is known about the stem rust resistance genes present in widely used wheat cultivars from Gansu. This study aimed to determine the resistance level at the seedling stage of the main wheat cultivars in Gansu Province. A secondary objective was to assess the prevalence ofSr2,Sr24,Sr25,Sr26,Sr31, andSr38using molecular markers. The results of the present study indicated that 38 (50.7%) wheat varieties displayed resistance to all the tested races ofPuccinia graminisf. sp.tritici.The molecular marker analysis showed that 13 out of 75 major wheat cultivars likely carriedSr2; 25 wheat cultivars likely carriedSr31; and nine wheat cultivars likely carriedSr38. No cultivar was found to haveSr25andSr26, as expected. Surprisingly, no wheat cultivars carriedSr24. The wheat lines with known stem rust resistance genes could be used as donor parent for further breeding programs.

Sign in / Sign up

Export Citation Format

Share Document