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Martin L Carson - One of the best experts on this subject based on the ideXlab platform.
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screening wild oat accessions from morocco for resistance to puccinia coronata
Plant Disease, 2013Co-Authors: Martin L CarsonAbstract:Abstract Here, we report the screening of 332 new accessions of 11 different wild oat (Avena) species from the United States Department of Agriculture National Small Grains Collection in Aberdeen, ID, for resistance to crown rust disease, caused by Puccinia coronata f. sp. Avenae. This collection originated from Morocco and includes Avena agadiriana, A. atlantica, A. barbata, A. damascena, A. eriantha, A. hirtula, A. longiglumis, A. magna, A. murphyi, A. sterilis, and A. wiestii. After screening this collection with a highly diverse population of P. coronata f. sp. Avenae, 164 accessions (49%) were rated moderately resistant to resistant in the preliminary screen at the seedling stage and 181 accessions (55%) rated moderately resistant to highly resistant in the adult plant stage. Although none of the accessions showed a highly resistant response consistently in the seedling stage, 20 accessions did display a highly resistant response in the adult plant stage. Both seedling as well as adult plant resistan...
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virulence in oat crown rust puccinia coronata f sp Avenae in the united states from 2006 through 2009
Plant Disease, 2011Co-Authors: Martin L CarsonAbstract:Abstract The use of race-specific seedling genes for resistance is the primary means of controlling crown rust of oat (Puccinia coronata f. sp. Avenae) in the United States. To better utilize those resistance genes, knowledge of the occurrence and frequency of corresponding virulence in the population of P. coronata f. sp. Avenae in the United States is essential. In total, 571 single-pustule isolates of oat crown rust were collected from cultivated and wild oat (Avena sativa and A. fatua, respectively) in the major oat production areas of the United States from 2006 through 2009. They were tested for virulence on seedlings of 31 differential oat lines in the greenhouse. In all, 201 races were found among the 357 isolates from the spring oat region of the north-central United States, and 140 races were found among 214 isolates from the southern winter oat region. The crown rust populations from the winter and spring oat regions were clearly differentiated from one another, differing in the frequency of vi...
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additional sources of broad spectrum resistance to puccinia coronata f sp Avenae from canadian accessions of Avena barbata
Plant Disease, 2010Co-Authors: Martin L CarsonAbstract:ABSTRACT Crown rust (Puccinia coronata f. sp. Avenae) is considered the most damaging disease of oat and the use of race-specific seedling (Pc) genes for resistance has been the primary means of control. As these resistance genes from cultivated oat, Avena sativa, and the wild hexaploid animated oat, A. sterilis, were deployed in oat cultivars, corresponding virulence in the U.S. crown rust population increased rapidly, such that the effective lifespan of a resistant cultivar in the United States is now 5 years or less. Introgression of resistance from diploid and tetraploid Avena spp. into hexaploid oat has been difficult due to the difference in ploidy levels and the lack of pairing of homeologous chromosomes between species. The wild tetraploid slender oat, A. barbata, has been a source of powdery mildew and stem rust resistance in cultivated oat but has largely been unexploited for crown rust resistance. A relatively high percentage of A. barbata accessions from the United States Department of Agricul...
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broad spectrum resistance to crown rust puccinia coronata f sp Avenae in accessions of the tetraploid slender oat Avena barbata
Plant Disease, 2009Co-Authors: Martin L CarsonAbstract:Carson, M. L. 2009. Broad-spectrum resistance to crown rust, Puccinia coronata f. sp. Avenae, in accessions of the tetraploid slender oat, Avena barbata. Plant Dis. 93:363-366. The use of race-specific seedling genes for resistance has been the primary means of controlling crown rust of oat (Puccinia coronata). As resistance genes from hexaploid cultivated oat, Avena sativa and, later, the wild hexaploid animated oat, A. sterilis, were deployed in oat cultivars, corresponding virulence in the crown rust population increased rapidly, such that the effective lifespan of a resistant cultivar in the United States is now 5 years or less. Introgression of resistance genes from diploid and tetraploid Avena spp. into hexaploid oat has been difficult due to differences in ploidy levels and the lack of homology of chromosomes between the two species. The wild tetraploid slender oat, A. barbata, has been a source of powdery mildew and stem rust resistance in cultivated oat but has largely been unexploited for crown rust resistance. In total, 359 accessions of A. barbata from the National Small Grains Collection were evaluated in seedling greenhouse tests. Of these accessions, 39% were at least moderately resistant when inoculated with a crown rust race with low virulence (DBBC). When tested further with a highly diverse bulk inoculum from the 2006 and 2007 St. Paul buckthorn nursery, 48 accessions (approximately 13%) were resistant. Many of these accessions were heterogeneous in reaction, but two accessions (PI320588 from Israel and PI337893 from Italy) were highly resistant (immune) and two others (PI337886 from Italy and PI367293 from Spain) consistently produced resistant reactions (chlorotic flecks) in all tests. Resistant accessions were found from throughout much of the natural range of A. barbata. Crosses of some of the better accessions have been made to cultivated oat.
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crown rust development and selection for virulence in puccinia coronata f sp Avenae in an oat multiline cultivar
Plant Disease, 2009Co-Authors: Martin L CarsonAbstract:ABSTRACT Crown rust, caused by Puccinia coronata f. sp. Avenae is the most important disease of cultivated oat in North America. Numerous race-specific (Pc) genes for crown rust have been found in Avena spp. but this type of resistance has not been durable when used in oat cultivars. Increasing diversity for resistance within a crop by the use of multiline cultivars or varietal mixtures has been proposed as a means of achieving durable resistance to highly variable pathogens such as P. coronata f. sp. Avenae. Multiline cv. E77 was evaluated over multiple seasons in the University of Minnesota buckthorn nursery in St. Paul. Buckthorn (Rhamnus cathartica, the alternate host of P. coronata) supports a sexually recombining, highly diverse crown rust population in the St. Paul nursery. Crown rust severity on flag leaves was measured multiple times on E77 and its 10 component lines during grain filling. Single-urediniospore isolates taken from crown rust samples during early stages of the epidemic and at the en...
W H P Boshoff - One of the best experts on this subject based on the ideXlab platform.
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occurrence and pathogenicity of puccinia coronata var Avenae f sp Avenae on oat in south africa
Crop Protection, 2020Co-Authors: W H P Boshoff, Z A Pretorius, T Terefe, B VisserAbstract:Abstract Crown rust, caused by Puccinia coronata Corda var. Avenae f. sp. Avenae (Urban & Markova) (Pca), can negatively impact oat (Avena sativa L.) production in South Africa and little is known about pathogenic variability and cultivar response. Pca infected leaves were obtained from oat trial plots, commercial fields and wild oat (Avena spp.) during the 2016 and 2017 growing seasons for race analysis. Uncharacterised collections from 1998 to 2005 were also included. Single pustule isolates were derived from field collections and used for race typing on 16 international differential lines. Six races were identified from 88 isolates pathotyped with race JBLL originating from wild oat samples, SGLL, SQPL and SSTL from commercial oat samples and SBLL+ from both wild and commercial oat samples. Isolates collected in 1998 typed as races SBLL and SBLL+ and the 2005 isolates as race SQPL. Race SBLL was not detected in the 2016 and 2017 samples with SBLL+ being dominant during 2016–17. This is the first report of South African races with virulence for the resistance genes Pc38, Pc58 and Pc59. Seedling infection types of 70 additional oat lines and cultivars to the described races showed incompatible phenotypes for 27 entries. Field data revealed moderate to high levels of adult plant resistance for a few cultivars to races SBLL+ and SSTL. Genetic analysis of 31 isolates, including two USA control isolates, revealed three genetic lineages. No apparent correlation was observed among year of collection, geographic origin, phenotype and genotype of isolates except for race JBLL that originated from wild oat collections in the Western Cape.
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pathogenic variability of puccinia coronata f sp Avenae and p graminis f sp Avenae on oat in south africa
Plant Disease, 2001Co-Authors: B D Van Niekerk, Z A Pretorius, W H P BoshoffAbstract:ABSTRACT Although crown rust (caused by Puccinia coronata f. sp. Avenae) and stem rust (caused by Puccinia graminis f. sp. Avenae) are generally considered to be the most widespread and damaging diseases of oat (Avena spp.) in South Africa, pathogenic variability has never been studied. During 1997 and 1998, one dominant crown rust pathotype (SBLL) was identified with virulence to resistance genes Pc40, Pc45, Pc46, Pc51, and Pc54. Four other pathotypes (SGLL, PBBB+Pc35, SDQL, and JBBM+Pc35), occurring at low frequencies and further rendering resistance genes Pc35, Pc39, Pc48, Pc50, Pc52, and Pc64 ineffective, were also detected. Resistance gene Pc40 was postulated in Wisconsin X1588-2; Pc51 in Euro, Maluti, Overberg, OX88I 075-106, Perdeberg, and Swartberg; and Pc39 was confirmed in the cultivar Fidler. During the same period, four stem rust pathotypes were identified with virulence to resistance genes Pg1, Pg2, Pg4, Pg8, Pg9, Pg12,Pg15, and Pga. Resistance gene Pga was postulated in Alpha, OX87 080-1, OX...
Chantre, Guillermo Rubén - One of the best experts on this subject based on the ideXlab platform.
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Manejo integrado de malezas: simulación del sistema multianual AVEFA-trigo/cebada
2018Co-Authors: Molinari, Franco Ariel, Blanco Anibal, Chantre, Guillermo RubénAbstract:El presente trabajo propone una herramienta basada en modelos matemáticos para la simulación de escenarios de manejo integrado de malezas. El modelo propuesto permite simular una maleza anual (Avena fatua L.) en competencia con cereales de invierno, trigo (Triticum aestivum L.) y cebada (Hordeum vulgare L.) en un plan de rotación de tres años. Desde la maleza se simula: (i) la dinámica demográfica diaria discriminando la composición numérica de los distintos estados fenológicos, (ii) competencia intraespecífica e interespecífica, (iv) producción de semillas y (v) el efecto de diferentes métodos de control. Referente a los cereales se simula: (i) índice de área foliar (IAF), (ii) competencia sobre la maleza y (iii) rendimiento esperado. El modelo ha sido desarrollado sobre la plataforma Microsoft Excel®, complementado con programación en Visual Basic. Se utilizó como caso de estudio una rotación de 3 años (AVEFA/TRIGO-AVEFA/CEBADA-AVEFA/TRIGO) característica de la región sur de la provincia de Buenos Aires, Argentina.Sociedad Argentina de Informática e Investigación Operativ
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Manejo integrado de malezas: simulación del sistema multianual AVEFA-trigo/cebada
2018Co-Authors: Molinari, Franco Ariel, Blanco Anibal, Chantre, Guillermo RubénAbstract:El presente trabajo propone una herramienta basada en modelos matemáticos para la simulación de escenarios de manejo integrado de malezas. El modelo propuesto permite simular una maleza anual (Avena fatua L.) en competencia con cereales de invierno, trigo (Triticum aestivum L.) y cebada (Hordeum vulgare L.) en un plan de rotación de tres años. Desde la maleza se simula: (i) la dinámica demográfica diaria discriminando la composición numérica de los distintos estados fenológicos, (ii) competencia intraespecífica e interespecífica, (iv) producción de semillas y (v) el efecto de diferentes métodos de control. Referente a los cereales se simula: (i) índice de área foliar (IAF), (ii) competencia sobre la maleza y (iii) rendimiento esperado. El modelo ha sido desarrollado sobre la plataforma Microsoft Excel®, complementado con programación en Visual Basic. Se utilizó como caso de estudio una rotación de 3 años (AVEFA/TRIGO-AVEFA/CEBADA-AVEFA/TRIGO) característica de la región sur de la provincia de Buenos Aires, Argentina
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Manejo Integrado de Malezas: un enfoque de simulación: aplicación al sistema AVEFA-Cebada
2017Co-Authors: Molinari, Franco Ariel, Blanco Anibal, Chantre, Guillermo RubénAbstract:El presente trabajo propone una aproximación computacional al Manejo Integrado de Malezas (MIM) por medio de un modelo matemático de simulación que tiene en cuenta la dinámica demográfica de una maleza anual en competencia con el cultivo. El modelo desarrollado permite simular: (i) la dinámica demográfica de la maleza, discriminando la composición numérica de los distintos estados fenológicos y la magnitud de los procesos demográficos, en función del impacto ejercido por las estrategias de control seleccionadas (químicas y no químicas); (ii) el nivel de competencia cultivo-maleza; y (iii) el rendimiento esperado del cultivo en función de las estrategias de manejo utilizadas. El modelo ha sido desarrollado sobre la plataforma Microsoft Excel® y programación en Visual Basic. Con fines demostrativos se utilizó como caso de estudio el sistema AVEFA (Avena fatua L.) – Cebada cervecera (Hordeum vulgare L.) característico de la región centro-sur de la provincia de Buenos Aires, Argentina.Sociedad Argentina de Informática e Investigación Operativa (SADIO
D D Stuthman - One of the best experts on this subject based on the ideXlab platform.
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Inheritance of resistance to loose smut of oat
Plant Disease, 1993Co-Authors: R D Wilcoxson, D. J. Miller, D D StuthmanAbstract:The percentage of plants infected with loose smut (Ustilago Avenae) was determined in oat (Avena sativa) parental cultivars and lines and in progenies after kernels were inoculated with water suspensions of teliospores by a vacuum procedure. Inheritance of resistance was studied with F 4 populations of three crosses. In cross Ogle/ND 820559 (susceptible/moderately resistant), the distribution of F 4 progenies appeared bimodal, with more of the progeny clustered around ND 820559 than around Ogle. Twenty-one percent of the F 4 lines displayed fewer infected plants than the resistant parent. In Don/Starter (resistantJresistant), the distribution of F 4 lines was skewed toward low incidence of infection, with many lines more susceptible than either parent
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evaluation of oats for resistance to loose smut
Plant Disease, 1993Co-Authors: R D Wilcoxson, D D StuthmanAbstract:The percentage of loose smut (Ustilago Avenae) infected plants in oat (Avena sativa) cultivars and breeding lines was determined after kernels were inoculated in a vacuum with water suspensions of teliospores. Fifty-two oat cultivars were evaluated between 1978 and 1990; 14 were resistant, six were moderately resistant, and 32 were susceptible. Many advanced breeding lines were also resistant. Factors that might affect the incidence of smut infection in evaluation trials were studied with cultivars Moore (moderately resistant), Ogle (susceptible), and Starter (resistant). One to three exposures in the vacuum during the inoculation procedure did not greatly affect the incidence of loose smut in the cultivars
Kathy Esvelt Klos - One of the best experts on this subject based on the ideXlab platform.
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new sources of adult plant and seedling resistance to puccinia coronata f sp Avenae identified among Avena sativa accessions from the national small grains collection
Plant Disease, 2018Co-Authors: Belayneh Admassuyimer, Shahryar F Kianian, Tyler Gordon, Stephen A Harrison, Harold E Bockelman, Michael J Bonman, Kathy Esvelt KlosAbstract:: Accessions of cultivated oat (Avena sativa L.) from the United States Department of Agriculture-Agricultural Research Service Small Grains Collection in Aberdeen, ID were characterized for adult plant resistance (APR) and seedling resistance to crown rust, caused by Puccinia coronata f. sp. Avenae. Initially, 607 oat accessions with diverse geographic origins were evaluated in field tests in Baton Rouge, LA. Of those, 97 accessions were not fully susceptible and were tested in the field in St. Paul, MN against a diverse P. coronata f. sp. Avenae population. Thirty-six accessions that had some level of resistance in both field tests and mean coefficients of infection of ≤20 were further evaluated for APR and seedling resistance. Among these, four accessions (PI 193040, PI 194201, PI 237090, and PI 247930) were resistant to eight P. coronata f. sp. Avenae races as seedlings. Twenty-nine accessions had resistance to at least one of the P. coronata f. sp. Avenae races. Three accessions (CIav 2272, CIav 3390, and PI 285583) were fully susceptible to all eight P. coronata f. sp. Avenae races as seedlings. Further evaluation of the three seedling-susceptible accessions at the flag leaf stage in a growth chamber resulted in moderately susceptible to moderately resistant responses. The resistance sources presented here may contain genes not deployed in elite oat varieties, and may be useful for future crown rust resistance breeding. The adult and seedling resistance found in accessions of the cultivated oat species is especially valuable because it avoids problems associated with the transfer of genes from wild species to cultivated oat.
