Análise multivariada dos componentes da resistência à ferrugem-asiática em genótipos de soja

Koga, Lucimara Junko; Canteri, Marcelo Giovanetti; Calvo, Éberson Sanches; Unfried, Jair Rogerio; Garcia, Alexandre; Harada, Arlindo; Kiihl, Romeu Afonso de Souza

doi:10.1590/s0100-204x2008001000004

Cited by 14 publications

(13 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In subsequent assays with the GA08 isolate in 2010 through 2012, PI 615445 did not develop sporulating lesions, suggesting the possibility of accidental seed contamination in the 2009 assay. When Koga et al (2008) compared lesion types and relative sporulation at 15 and 29 d after inoculation, one‐third of the soybean genotypes that had RB lesions after 15 d had developed a mixture of RB and TAN lesions by 29 d after inoculation, but none had only TAN lesions, and sporulation intensity stayed the same or increased only slightly during the same period. It therefore seems unlikely that time or environmental conditions alone could have accounted for the variability in the reactions of PI 615445 observed in our assays.…”

Section: Resultsmentioning

confidence: 99%

Soybean Germplasm Accession Seedling Reactions to Soybean Rust Isolates from Georgia

et al. 2014

View full text Add to dashboard Cite

Soybean rust (SBR), caused by Phakopsora pachyrhizi Syd. and P. Syd., is a threat to soybean [Glycine max (L.) Merr.], production in regions of the world where winters are not cold enough to completely eliminate the many hosts of the fungus, so resistant soybean cultivars would be useful in managing this disease. Resistant germplasm accessions have been identified, and resistance (Rpp) genes have been mapped to six independent loci, but the high degree of virulence variability among P. pachyrhizi populations and isolates means that the level of resistance to different populations and isolates can vary considerably. Greenhouse assays were conducted from 2008 until 2013 in which seedlings of soybean plant introductions were challenged with bulk P. pachyrhizi isolates collected in the state of Georgia. Accessions were included in the tests either because they carried known Rpp genes or because they had appeared resistant to SBR in previous field assays. The resistance was assessed on the basis of infection type, visible urediniospore development, and sometimes lesion density. With a few exceptions, most of the accessions that appeared resistant as adult plants in the field also had resistance reactions as seedlings, and these reactions were generally similar or identical in the different years that the greenhouse assays were conducted. This study demonstrates that greenhouse seedling reactions should usually be reliable indicators of adult plant resistance to related P. pachyrhizi isolates or populations, and confirms the resistance of more than 100 soybean germplasm accessions to fungal isolates and field populations from Georgia.

show abstract

Section: Resultsmentioning

confidence: 99%

Soybean Germplasm Accession Seedling Reactions to Soybean Rust Isolates from Georgia

et al. 2014

View full text Add to dashboard Cite

show abstract

“…This line carries a recessive allele that confers RB-type resistance to lesions caused by the pathogen. But this type of resistance does not prevent the appearance of lesions, it only decreases their severity (Koga et al, 2008). RB-type lesions are actually hyper-sensitivity reactions that reduce the pathogen multiplication and disease incidence by reducing the number of uredia and spore production (Pierozzi et al, 2008).…”

Section: Resultsmentioning

confidence: 99%

Selection strategies of segregant soybean populations for resistance to Asian rust

Ribeiro

Toledo

Ramalho

2009

Pesq. agropec. bras.

View full text Add to dashboard Cite

-The objective of this work was to identify the best selection strategies for the more promising parental combinations to obtain lines with good resistance to soybean Asian rust (Phakopsora pachyrhizi). Two experiments were carried out in the field during the 2006/2007 and 2007/2008 growing seasons, to determine the percentage of infected leaf area of individual plants of five parents and their segregant F 2 and F 3 populations. The data obtained indicates that additive genetic variance predominates in the control of soybean resistance to Asian rust, and that the year and time of assessment do not significantly influence the estimates of the genetic parameters obtained. The narrow-sense heritability (h 2 r ) ranged from 23.12 to 55.83%, and indicates the possibility of successful selection of resistant individuals in the early generations of the breeding program. All the procedures used to select the most promising populations to generate superior inbred lines for resistance to P. pachyrhizi presented similar results and identified the BR01-18437 x BRS 232 population as the best for inbred line selection.Index terms: Glycine max, Phakopsora pachyrhizi, additive variance, heritability, selection. Estratégias de seleção de populações segregantes de soja para resistência à ferrugem-asiáticaResumo -O objetivo deste estudo foi identificar as estratégias mais eficientes para selecionar as combinações parentais mais promissoras e obter linhas com bom grau de resistência à ferrugem-asiática da soja (Phakopsora pachyrhizi). Dois experimentos foram realizados em campo nos anos agrícolas 2006/2007 e 2007/2008, para avaliar a percentagem da área foliar infectada em plantas individuais de cinco parentais e das suas populações segregantes F 2 e F 3 . Os dados obtidos indicam que a variância genética aditiva predomina no controle da resistência da soja à ferrugem-asiática e que os anos e as épocas de avaliação não influenciaram significativamente as estimativas dos parâmetros genéticos obtidos. A herdabilidade no sentido restrito (h 2 r ) variou de 23,12 a 55,83%, o que indica a possibilidade de sucesso com a seleção de indivíduos resistentes em gerações precoces nos programas de melhoramento. Todos os procedimentos usados para selecionar as populações mais promissoras na geração de linhagens superiores quanto à resistência a P. pachyrhizi apresentaram resultados similares e identificaram a população BR01-18437 x BRS 232 como a melhor para a seleção de linhagens.Termos para indexação: Glycine max, Phakopsora pachyrhizi, variância aditiva, herdabilidade, seleção.

show abstract

“…Recentemente, no Brasil, diversos trabalhos têm sido realizados para se conhecer os mecanismos de resistência à ferrugem-asiática-da-soja, sejam estes qualitativos (Santos et al, 2007;Silva et al, 2007;Costa et al, 2008;Laperuta et al, 2008;Morceli et al, 2008) ou quantitativos (Koga et al, 2008;Ribeiro et al, 2009aRibeiro et al, , 2009bCruz et al, 2011). A associação de mecanismos qualitativos, por meio da piramidação de genes de resistência, e de mecanismos quantitativos, de resistência horizontal, deve ser utilizada como estratégia dos programas de melhoramento de soja, para que se possa obter resistência mais duradoura.…”

Section: Iniciadorunclassified

Variabilidade genética de Phakopsora pachyrhizi avaliada por meio de marcadores microssatélites

Tschurtschenthaler

Vieira

Nora³

et al. 2012

Pesq. agropec. bras.

View full text Add to dashboard Cite

Resumo -O objetivo deste trabalho foi avaliar a variabilidade genética da ferrugem-asiática-da-soja no Brasil, com uso de marcadores microssatélites. Populações de esporos de Phakopsora pachyrhizi coletadas nas regiões Sul, Sudeste e Centro Oeste do país foram submetidas à análise de variabilidade genética, avaliada por meio de marcadores microssatélites específicos para o fungo. Foram coletadas, também, populações de fungo em diversas variedades de soja em uma mesma localidade, incluindo populações com lesão "reddish-brown" (RB). Entre essas populações, não houve variabilidade. Tecidos com lesões RB não apresentaram esporos do fungo e não amplificaram com os marcadores específicos para P. pachyrhizi. A variabilidade genética entre as populações coletadas nas três regiões variou de 0 a 0,36. Observou-se tendência de agrupamento das populações da região Sul e Centro Oeste do Brasil em grupos diferentes. A existência de variabilidade genética em populações de P. pachyrhizi é um indicativo de que a resistência genética vertical, conferida por genes únicos, é uma estratégia de risco para os programas de melhoramento genético que visam a resistência à ferrugem-asiática-da-soja no Brasil.Termos para indexação: Glycine max, diversidade genética, ferrugem-asiática-da-soja, resistência genética, resistência vertical, SSR. Genetic variability of Phakopsora pachyrhizi accessed by microsatellite markersAbstract -The objective of this work was to evaluate the genetic variability of Asian soybean rust in Brazil using microsatellite markers. Samples of Phakopsora pachyrhizi spores collected in the Southern, Southeastern, and Central West regions of Brazil were subjected to analysis of genetic variability, accessed with microsatellite markers specific for the fungus. Spores of the fungus were also collected in several soybean varieties in a same locality, including samples with reddish-brown (RB) lesions. Among these samples, there was no variability. Tissues with RB lesions did not contain spores of the fungus and did not amplify with the specific markers for P. pachyrhizi. Genetic variability among samples collected in the three regions ranged from 0 to 0.36. A tendency to cluster samples of the Southern and Central West regions of Brazil in different groups was observed. The existence of genetic variability in P. pachyrhizi spore populations indicates that vertical genetic resistance, provided by single genes, is a risky strategy for soybean breeding programs that aim resistance to Asian soybean rust.

show abstract

Análise multivariada dos componentes da resistência à ferrugem-asiática em genótipos de soja

Cited by 14 publications

References 24 publications

Soybean Germplasm Accession Seedling Reactions to Soybean Rust Isolates from Georgia

Soybean Germplasm Accession Seedling Reactions to Soybean Rust Isolates from Georgia

Selection strategies of segregant soybean populations for resistance to Asian rust

Variabilidade genética de Phakopsora pachyrhizi avaliada por meio de marcadores microssatélites

Contact Info

Product

Resources

About