scholarly journals Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2000

Plant Disease ◽  
2002 ◽  
Vol 86 (9) ◽  
pp. 981-986 ◽  
Author(s):  
D. L. Long ◽  
J. A. Kolmer ◽  
K. J. Leonard ◽  
M. E. Hughes
Keyword(s):  
United States ◽  
Leaf Rust ◽  
Great Plains ◽  
Gulf Coast ◽  
Rust Fungus ◽  
Puccinia Triticina ◽  
The United States ◽  
Wheat Leaf Rust ◽  
Ohio Valley ◽  
Wheat Leaf

Collections of Puccinia triticina were obtained from rust infected wheat leaves by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, Gulf Coast, and Atlantic Coast States in order to determine the virulence of the wheat leaf rust fungus in 2000. Single uredinial isolates (1,120 in total) were derived from the wheat leaf rust collections and tested for virulence phenotype on 16 lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes. In the United States in 2000, 54 virulence phenotypes of P. triticina were found. Virulence phenotypes MBDS and MCDS, which are virulent to resistance gene Lr17, were the first and third most common phenotypes in the United States and were found in the Great Plains and the Ohio Valley regions. MCRK, which is virulent to Lr26, was the second most common phenotype and was found primarily in the Southeast, Ohio Valley, and Northeast regions. In the northern area of the Great Plains, phenotypes with virulence to Lr16 increased in frequency from 1998 and 1999. The Southeast and Great Plains regions had different predominant virulence phenotypes, which indicates that populations of P. triticina in those areas are not closely connected. The northern and southern areas of the Great Plains region had the same predominant virulence phenotypes, indicating movement of virulence phenotypes of P. triticina within this region.

scholarly journals Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2002

Plant Disease ◽  
2004 ◽  
Vol 88 (10) ◽  
pp. 1079-1084 ◽  
Author(s):  
J. A. Kolmer ◽  
D. L. Long ◽  
M. E. Hughes
Keyword(s):  
United States ◽  
Leaf Rust ◽  
Great Plains ◽  
Puccinia Triticina ◽  
The United States ◽  
Wheat Leaf Rust ◽  
Ohio Valley ◽  
Virulence Phenotype ◽  
Common Phenotype ◽  
Wheat Leaf

Collections of Puccinia triticina were obtained from rust-infected wheat leaves by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, Southeast, California, and the Pacific Northwest, in order to determine the virulence of the wheat leaf rust fungus in 2002. Single uredinial isolates (785 in total) were derived from the wheat leaf rust collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17, Lr30, LrB, Lr10, Lr14a, and Lr18. In the United States in 2002, 52 virulence phenotypes of P. triticina were found. Virulence phenotype MBDS, which is virulent to resistance gene Lr17, was the most common phenotype in the United States. MBDS was found in the Southeast, Great Plains, and the Ohio Valley regions, and also in California. Phenotype MCDS, virulent to Lr17 and Lr26, was the second most common phenotype and occurred in the same regions as MBDS. Virulence phenotype THBJ, which is virulent to Lr16 and Lr26, was the third most common phenotype, and was found in the southern and northern central Great Plains region. Phenotype TLGJ, with virulence to Lr2a, Lr9, and Lr11, was the fourth most common phenotype and was found primarily in the Southeast and Ohio Valley regions. The Southeast and Ohio Valley regions differed from the Great Plains regions for predominant virulence phenotypes, which indicate that populations of P. triticina in those areas are not closely connected. The northern and southern areas of the Great Plains were similar for frequencies of predominant phenotypes, indicating a strong south to north migration of urediniospores.

scholarly journals Virulence and Diversity of Wheat Leaf Rust in the United States in 1993 to 1995

Plant Disease ◽  
1998 ◽  
Vol 82 (12) ◽  
pp. 1391-1400 ◽  
Author(s):  
D. L. Long ◽  
K. J. Leonard ◽  
J. J. Roberts
Keyword(s):  
United States ◽  
Leaf Rust ◽  
Great Plains ◽  
Gulf Coast ◽  
Puccinia Triticina ◽  
Leaf Rust Resistance ◽  
The United States ◽  
Eastern United States ◽  
Ohio Valley ◽  
Wheat Leaf

Isolates of Puccinia triticina were obtained from wheat leaf collections made by cooperators throughout the United States and from cereal rust field surveys of the Great Plains, Ohio Valley, and Gulf Coast states in 1993, 1994, and 1995. Sixty-two virulence/avirulence phenotypes on 14 host lines that are near-isogenic for leaf rust resistance were found among 681 single uredinial isolates in 1993, 42 phenotypes were found among 683 isolates in 1994, and 51 among 701 isolates in 1995. As in previous surveys, regional race distribution patterns showed that the central United States is a single epidemiological unit distinct from the eastern United States. The distinctive racial composition of collections from the Southeast, Northeast, and Ohio Valley indicates that populations of P. triticina in those areas are discrete, suggesting epidemics originate from localized overwintering sources.

scholarly journals First Report of a Wheat Leaf Rust (Puccinia triticina) Phenotype with High Virulence to Durum Wheat in the Great Plains Region of the United States

Plant Disease ◽  
2015 ◽  
Vol 99 (1) ◽  
pp. 156-156 ◽  
Author(s):  
J. A. Kolmer
Keyword(s):  
United States ◽  
Durum Wheat ◽  
Leaf Rust ◽  
Great Plains ◽  
Puccinia Triticina ◽  
The United States ◽  
Wheat Leaf Rust ◽  
High Virulence ◽  
Wheat Leaf ◽  
Infection Types

Phenotypes of the wheat leaf rust pathogen Puccinia triticina with high virulence to tetraploid durum wheat (Triticum turgidum) are found regularly in Mexico (5), the Mediterranean region (1), the Middle East (3), and rarely in the Imperial Valley of California and the adjacent area in Arizona. Previous to 2013, these phenotypes had not been found in the Great Plains region of the United States where hexaploid, T. aestivum types of hard red winter wheat, hard red spring wheat, and durum wheat are grown. In May 2013, collections of P. triticina, the wheat leaf rust fungus identified by color, size, and shape of uredinia, were obtained from leaves of the hard red winter wheat cultivar Overley in research plots at Hutchinson, KS. A single uredinial isolate was obtained that was used in virulence testing and molecular genotyping. Urediniospores from the initial field collection were inoculated onto seedlings of the susceptible cultivar Little Club. Subsequently, single uredinia were isolated and re-increased on Little Club. The single uredinial isolate was initially inoculated to 7-day-old seedlings of 20 lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes and are used in the annual virulence surveys of P. triticina in the United States (2). The phenotype of the isolate, based on virulence to the 20 differential lines, was BBBQD (2), which was identical to phenotypes of P. triticina with high virulence to durum wheat from other regions where durum wheat is commonly grown (4). This phenotype had intermediate infection type of 2+ (moderate size uredinia with chlorosis) to the line with Lr2c and high infection types of 3+ (large uredinia with no chlorosis or necrosis) to lines with genes LrB, Lr10, and Lr39/41. Overley wheat has Lr39/41. The isolate was further tested on an additional set of 27 Thatcher lines, the cultivar Gatcher with Lr27 + Lr31, and a set of 15 durum wheat cultivars that have been grown in the United States and Canada. The isolate had virulence to lines with genes Lr14b, Lr20, Lr23, Lr33, Lr44, and Lr64. Notably, the isolate had distinct low infection types to seedlings of Thatcher lines with genes Lr12, Lr13, Lr22a, Lr35, and Lr37 that are usually optimally expressed in adult plants to most P. triticina isolates. The isolate had high virulence to all of the durum wheat cultivars. The single uredinial isolate of P. triticina from Overley was also genotyped with microsatellite alleles used in previous studies with P. triticina collections from durum wheat (3). The isolate from Kansas had a highly similar genotype to other isolates of P. triticina from worldwide durum-producing regions (3). This isolate with high virulence to durum wheat most likely migrated to the southern Great Plains region from the durum-growing regions in Mexico. Cultivars such as TAM 112, Armour, Winterhawk, and Bullet with Lr39/41 and other cultivars with Overley in their pedigree are currently grown throughout the southern Great Plains. Since many of the P. triticina phenotypes with high virulence to durum wheat are virulent to Lr39/41, these cultivars may provide a pathway for the spread of these phenotypes to the major durum-producing areas of North Dakota and Saskatchewan. References: (1) H. J. Goyeau et al. Plant Pathol. 61:761, 2012. (2) J. A. Kolmer and M. A. Hughes. Plant Dis. 97:1103, 2013. (3) M. E. Ordoñez and J. A. Kolmer. Phytopathology 97:574, 2007. (4) M. E. Ordoñez and J. A. Kolmer. Phytopathology 97:344, 2007. (5) R. P. Singh et al. Plant Dis. 88:703, 2004.

Virulence phenotypes of the wheat leaf rust pathogen, Puccinia triticina, in the United States 2018-2020

Plant Disease ◽  
2022 ◽  
Author(s):  
James Kolmer ◽  
Oluseyi Fajolu
Keyword(s):  
United States ◽  
Winter Wheat ◽  
Leaf Rust ◽  
Great Plains ◽  
Rust Fungus ◽  
Puccinia Triticina ◽  
The United States ◽  
Northern Great Plains ◽  
Ohio Valley ◽  
Red Winter Wheat

Collections of wheat leaves infected with the leaf rust fungus, Puccinia triticina, were obtained from the southeastern states, the Ohio Valley, the Great Plains, and Washington in 2018, 2019 and 2020 to determine the prevalent virulence phenotypes in the wheat growing regions of the United States. In the hard red winter wheat region of the southern and mid Great Plains, MNPSD, and MPPSD were the two most common phenotypes in 2018 and 2019. In 2020 BBBQD with high virulence to durum wheat was the most common phenotype in the southern Great Plains. In the hard red spring wheat region of the northern Great Plains, MNPSD, MPPSD, MBDSD, and TBBGS were the predominant phenotypes. In the soft red winter wheat region of the southeastern states and Ohio Valley region, MBTNB, MCTNB, and MNPSD were the three most common phenotypes. Collections in Washington had phenotypes LBDSG, LCDSG, LCDJG, and MBDSB that were not found in any other region. Isolates with virulence to Lr11 were most frequent in the southeastern states, and Ohio Valley regions. The frequency of isolates with virulence to Lr39 was highest in the Great Plains region and frequency of isolates with virulence to Lr21 was highest in the northern Great Plains region. Selection of virulence phenotypes by leaf rust resistance genes in the different market classes of wheat, combined with the effects of clonal reproduction, overwintering in southern regions, and low migration between the Great Plains region and eastern wheat producing regions, has maintained the different P. triticina populations in the United States.

scholarly journals Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2003

Plant Disease ◽  
2005 ◽  
Vol 89 (11) ◽  
pp. 1201-1206 ◽  
Author(s):  
J. A. Kolmer ◽  
D. L. Long ◽  
M. E. Hughes
Keyword(s):  
United States ◽  
Leaf Rust ◽  
Great Plains ◽  
Puccinia Triticina ◽  
The United States ◽  
Wheat Cultivars ◽  
Ohio Valley ◽  
Virulence Phenotype ◽  
Common Phenotype ◽  
Wheat Leaf

Collections of Puccinia triticina were obtained from rust infected wheat leaves by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, Southeast, California, and the Pacific Northwest, in order to determine the virulence of the wheat leaf rust fungus in 2003. Single uredinial isolates (580 in total) were derived from the wheat leaf rust collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17, Lr30, LrB, Lr10, Lr14a, and Lr18. In the United States in 2003, 52 virulence phenotypes of P. triticina were found. Virulence phenotype MBDS, which has been selected by virulence to resistance gene Lr17, was the most common phenotype in the United States. MBDS was found in the Southeast, Great Plains, the Ohio Valley, and California. Virulence phenotype THBJ, which has been selected by virulence to genes Lr16 and Lr26, was the second most common phenotype, and was found in the southern and northern central Great Plains region. Phenotype MCDS, which has been selected by virulence to genes Lr17 and Lr26, was the third most common phenotype and occurred in the same regions as MBDS. The use of wheat cultivars with leaf rust seedling resistance genes has selected leaf rust phenotypes with virulence to genes Lr9, Lr16, Lr17, Lr24, and Lr26. The population of P. triticina in the United States is highly diverse for virulence phenotypes, which will continue to present a challenge for the development of wheat cultivars with effective durable resistance.

scholarly journals Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2013

Plant Disease ◽  
2015 ◽  
Vol 99 (9) ◽  
pp. 1261-1267 ◽  
Author(s):  
J. A. Kolmer ◽  
M. E. Hughes
Keyword(s):  
United States ◽  
Winter Wheat ◽  
Leaf Rust ◽  
Great Plains ◽  
Puccinia Triticina ◽  
The United States ◽  
Northern Great Plains ◽  
Ohio River ◽  
Ohio Valley ◽  
Red Winter Wheat

Collections of Puccinia triticina were obtained from rust-infected leaves provided by cooperators throughout the United States and from wheat fields and breeding plots by USDA-ARS personnel and cooperators in the Great Plains, Ohio River Valley, and southeastern states in order to determine the virulence of the wheat leaf rust population in 2013. Single uredinial isolates (490 total) were derived from the collections and tested for virulence phenotype on 20 lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes. In 2013, 79 virulence phenotypes were described in the United States. Virulence phenotypes MBTNB, TNBGJ, and MCTNB were the three most common phenotypes. Phenotypes MBTNB and MCTNB are both virulent to Lr11, and MCTNB is virulent to Lr26. MBTNB and MCTNB were most common in the soft red winter wheat region of the southeastern states and Ohio Valley. Phenotype TNBGJ is virulent to Lr39/41 and was widely distributed throughout the hard red winter wheat region of the Great Plains. Isolates with virulence to Lr11, Lr18, and Lr26 were common in the southeastern states and Ohio Valley region. Isolates with virulence to Lr21, Lr24, and Lr39/41 were frequent in the hard red wheat region of the southern and northern Great Plains.

scholarly journals Virulence of Puccinia triticina on Wheat in the United States in 1999

Plant Disease ◽  
2002 ◽  
Vol 86 (1) ◽  
pp. 15-19 ◽  
Author(s):  
D. L. Long ◽  
K. J. Leonard ◽  
M. E. Hughes
Keyword(s):  
United States ◽  
Great Plains ◽  
Gulf Coast ◽  
Puccinia Triticina ◽  
Leaf Rust Resistance ◽  
Distribution Patterns ◽  
The United States ◽  
Eastern United States ◽  
Ohio Valley ◽  
Central United States

Isolates of Puccinia triticina were obtained from wheat leaf collections made by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, and Gulf Coast states in 1999. Pathogenic races were determined from virulence/avirulence phenotypes on 14 host lines that are near-isogenic for leaf rust resistance. We found 58 races among 1,180 isolates in 1999. As in previous surveys, regional race distribution patterns showed that the central United States is a single epidemiological unit distinct from the eastern United States. The distinctive racial composition of collections from the Southeast, Northeast, and Ohio Valley indicates that populations of P. triticina in those areas are not closely connected, suggesting epidemics originate from localized overwintering sources.

scholarly journals Virulence of Puccinia triticina on Wheat in the United States from 1996 to 1998

Plant Disease ◽  
2000 ◽  
Vol 84 (12) ◽  
pp. 1334-1341 ◽  
Author(s):  
D. L. Long ◽  
K. J. Leonard ◽  
M. E. Hughes
Keyword(s):  
United States ◽  
Great Plains ◽  
Gulf Coast ◽  
Puccinia Triticina ◽  
Leaf Rust Resistance ◽  
Distribution Patterns ◽  
The United States ◽  
Eastern United States ◽  
Ohio Valley ◽  
Central United States

Isolates of Puccinia triticina were obtained from wheat leaf collections made by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, and Gulf Coast states in 1996, 1997, and 1998. Virulence-avirulence phenotypes were determined on 14 host lines that are near-isogenic for leaf rust resistance. We found 31 phenotypes among 277 single uredinial isolates in 1996, 56 phenotypes among 989 isolates in 1997, and 43 phenotypes among 989 isolates in 1998. As in previous surveys, regional race distribution patterns showed that the central United States is a single epidemiological unit distinct from the eastern United States. The distinctive racial composition of collections from the southeast, northeast, and Ohio Valley indicate that populations of P. triticina in those areas are not closely connected, suggesting that epidemics originate from localized overwintering sources.

scholarly journals Virulence of Puccinia triticina, the Wheat Leaf Rust Fungus, in the United States in 2017

Plant Disease ◽  
2019 ◽  
Vol 103 (8) ◽  
pp. 2113-2120 ◽  
Author(s):  
J. A Kolmer
Keyword(s):  
Winter Wheat ◽  
Leaf Rust ◽  
Great Plains ◽  
Rust Fungus ◽  
Puccinia Triticina ◽  
Leaf Rust Resistance ◽  
The United States ◽  
Wheat Cultivars ◽  
Ohio Valley ◽  
Red Winter Wheat

Samples of wheat leaves infected with the leaf rust fungus, Puccinia triticina, were obtained in 2017 from agricultural experiment station plots, demonstration plots, and farm fields in the Great Plains, the Ohio Valley, the southeastern states, California, and Washington in order to determine the prevalent virulence phenotypes present in the United States. A total of 65 virulence phenotypes were identified among the 469 single uredinial isolates that were tested on 20 near-isogenic lines of Thatcher wheat that differ for leaf rust resistance genes. Virulence phenotypes MBTNB at 11.3% of the overall population, and MCTNB at 7.0%, were the first and third most common phenotypes. Both phenotypes were found mostly in the southeastern states and Ohio Valley region. Phenotype TFTSB at 10.9% was the second most common phenotype and was found mostly in southern Texas. Virulence to leaf rust resistance gene Lr39, which is present in hard red winter wheat cultivars, was highest in the Great Plains region. Virulence to Lr11 and Lr18, which are present in soft red winter wheat cultivars, was highest in the southeastern states and Ohio Valley region. Virulence to Lr21, which is present in hard red spring wheat cultivars, was highest in the northern Great Plains region. The predominate P. triticina phenotypes from the soft red winter wheat regions of the southeastern states and Ohio Valley area differed from those in the hard red winter and hard red spring wheat areas of the Great Plains region. Collections from Washington had unique virulence phenotypes that had not been previously detected.

scholarly journals Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2001

Plant Disease ◽  
2003 ◽  
Vol 87 (7) ◽  
pp. 859-866 ◽  
Author(s):  
J. A. Kolmer ◽  
D. L. Long ◽  
E. Kosman ◽  
M. E. Hughes
Keyword(s):  
United States ◽  
Leaf Rust ◽  
Great Plains ◽  
Resistance Genes ◽  
Puccinia Triticina ◽  
Leaf Rust Resistance ◽  
The United States ◽  
Ohio Valley ◽  
Virulence Phenotype ◽  
Common Phenotype

Collections of Puccinia triticina were obtained from rust-infected wheat leaves by cooperators throughout the United States and from surveys of wheat fields and nurseries in the Great Plains, Ohio Valley, Gulf Coast, California, Pacific Northwest, and Atlantic Coast States in order to determine the virulence of the wheat leaf rust fungus in 2001. Single uredinial isolates (477 in total) were derived from the wheat leaf rust collections and tested for virulence phenotype on lines of Thatcher wheat that are near-isogenic for leaf rust resistance genes Lr1, Lr2a, Lr2c, Lr3, Lr9, Lr16, Lr24, Lr26, Lr3ka, Lr11, Lr17, Lr30, LrB, Lr10, Lr14a, and Lr18. The isolates also were tested for virulence on adult plants with leaf rust resistance genes Lr12, Lr13, Lr22a, Lr22b, Lr34, Lr35, and Lr37. In the United States in 2001, 44 virulence phenotypes of P. triticina were found. Virulence phenotype MBDS, which is virulent to resistance gene Lr17, was the most common phenotype in the United States. MBDS was found in the Southeast, Great Plains, and Ohio Valley regions. Virulence phenotype THBJ, which is virulent to Lr16 and Lr26, was the second most common phenotype, and occurred almost exclusively in the north-central Great Plains region. Phenotype MCDS, which is virulent to Lr17 and Lr26, was the third most common phenotype and was found primarily in the Southeast, Ohio Valley, and Great Plains regions. The Southeast and Ohio Valley regions differed from the Great Plains region for predominant virulence phenotypes, which indicate that populations of P. triticina in those areas are not closely connected. The northern and southern areas of the Great Plains region differed for phenotypes with virulence to Lr16; however, the two areas had other phenotypes in common. Virulence to the adult plant resistance genes Lr35 and Lr37 was detected for the first time in North America in the MBDS, MCJS, and MCDS phenotypes.

Sign in / Sign up

Export Citation Format

Share Document