scholarly journals Virulence Structure and Diversity of Puccinia coronata f. sp. avenae P. Syd. & Syd. in Poland During 2013 to 2015

Plant Disease ◽  
2019 ◽  
Vol 103 (7) ◽  
pp. 1559-1564 ◽  
Author(s):  
Edyta Paczos-Grzęda ◽  
Sylwia Sowa
Keyword(s):  
Resistance Genes ◽  
Rust Fungus ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
Sources Of Resistance ◽  
Global Center ◽  
Major Resistance Genes ◽  
Evenness Indices ◽  
Many Sources ◽  
High Level

The crown rust fungus Puccinia coronata f. sp. avenae P. Syd. & Syd. (Pca) attacks cultivated oat and its wild relatives, causing significant losses to the crop worldwide. Although understanding the origin and dynamics of the pathogen’s diversity is critical to developing methods for its control, there are little relevant data on Pca virulence diversity in Europe, the global center of oat production. The goal of this study was to analyze the diversity of Pca populations in Poland in 2013 to 2015 based on their ability to overcome currently available host resistance Pc genes. Pca isolate virulence was evaluated on a panel of lines containing 26 major resistance genes of oat. The isolates were able to overcome from 1 to 16 resistance genes each, with most isolates being virulent on five to seven lines. In all years, a very high level of crown rust pathotype diversity was observed, with Simpson and Evenness indices of 0.99. In total, 156 different pathotypes were detected, with no prevalent pathotype in any of the 3 years analyzed. The results showed that the virulence level of P. coronata isolates was relatively low for each year studied (21% on average), most likely owing to the low take up of Pc genes in Polish oat cultivars, meaning that many sources of resistance are still effective against Pca races occurring in Poland. The long-range dispersal of Puccinia spores supported by the availability of wild, weedy, and cultivated Avena species makes it likely that the virulence profile seen in Poland is representative of much of central Europe and beyond.

VIRULENCE OF UREDIAL AND AECIAL ISOLATES OF PUCCINIA CORONATA CORDA F.SP. AVENAE IDENTIFIED IN CANADA FROM 1952 TO 1966

1967 ◽  
Vol 45 (9) ◽  
pp. 1693-1701 ◽  
Author(s):  
George Fleischmann
Keyword(s):  
Rust Resistance ◽  
The United States ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
Santa Fe ◽  
Sources Of Resistance ◽  
Subsequent Increase ◽  
Crown Rust Resistance ◽  
Physiologic Races ◽  
Oat Breeding

Isolates of Puccinia coronata f.sp. avenae collected during a 15-year period were tested for virulence on the crown rust differential oat varieties. The proportion of cultures virulent on Landhafer increased relative to others during this period, and was related to the release in the United States of commercial varieties that contained this type of resistance. These varieties served to reduce the proportion of races avirulent on Landhafer in the crown rust population that reached Canada.The occurrence and subsequent increase in frequency of isolates virulent on Victoria was correlated with the release of the oat varieties Rodney and Garry which possess part of the crown rust resistance of Victoria. The increased proportion of cultures that attacked Ukraine also paralleled the release of these two commercial varieties. This suggests that Ukraine either contains the Victoria Pc-11 gene for crown rust resistance that was transferred to Rodney and Garry, or that it contains another gene in common with these varieties.Races of crown rust that are differentially virulent on the varieties Landhafer and Santa Fe have recently been found in Canada. One culture was virulent on the variety Bondvic but not on Trispernia. No increase in race 264 of crown rust, which attacks all the differential sources of resistance except Saia, has been observed since it was first identified in Canada in 1957.Presentation of the virulence of crown rust isolates for individual types of resistance was found to express the results of race surveys in terms which were more meaningful to the oat breeding program. This form of analysis also produced valuable information on the possible relationships of genes for resistance in different oat varieties not readily obtainable from conventional information on the occurrence and distribution of physiologic races of crown rust.

scholarly journals De Novo Assembly and Phasing of Dikaryotic Genomes from Two Isolates of Puccinia coronata f. sp. avenae, the Causal Agent of Oat Crown Rust

mBio ◽  
2018 ◽  
Vol 9 (1) ◽  
Author(s):  
Marisa E. Miller ◽  
Ying Zhang ◽  
Vahid Omidvar ◽  
Jana Sperschneider ◽  
Benjamin Schwessinger ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
De Novo ◽  
Rust Fungus ◽  
Expression Patterns ◽  
Haplotype Diversity ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
Small Subset ◽  
Nucleotide Polymorphisms ◽  
Oat Crown Rust

ABSTRACT Oat crown rust, caused by the fungus Pucinnia coronata f. sp. avenae, is a devastating disease that impacts worldwide oat production. For much of its life cycle, P. coronata f. sp. avenae is dikaryotic, with two separate haploid nuclei that may vary in virulence genotype, highlighting the importance of understanding haplotype diversity in this species. We generated highly contiguous de novo genome assemblies of two P. coronata f. sp. avenae isolates, 12SD80 and 12NC29, from long-read sequences. In total, we assembled 603 primary contigs for 12SD80, for a total assembly length of 99.16 Mbp, and 777 primary contigs for 12NC29, for a total length of 105.25 Mbp; approximately 52% of each genome was assembled into alternate haplotypes. This revealed structural variation between haplotypes in each isolate equivalent to more than 2% of the genome size, in addition to about 260,000 and 380,000 heterozygous single-nucleotide polymorphisms in 12SD80 and 12NC29, respectively. Transcript-based annotation identified 26,796 and 28,801 coding sequences for isolates 12SD80 and 12NC29, respectively, including about 7,000 allele pairs in haplotype-phased regions. Furthermore, expression profiling revealed clusters of coexpressed secreted effector candidates, and the majority of orthologous effectors between isolates showed conservation of expression patterns. However, a small subset of orthologs showed divergence in expression, which may contribute to differences in virulence between 12SD80 and 12NC29. This study provides the first haplotype-phased reference genome for a dikaryotic rust fungus as a foundation for future studies into virulence mechanisms in P. coronata f. sp. avenae. IMPORTANCE Disease management strategies for oat crown rust are challenged by the rapid evolution of Puccinia coronata f. sp. avenae, which renders resistance genes in oat varieties ineffective. Despite the economic importance of understanding P. coronata f. sp. avenae, resources to study the molecular mechanisms underpinning pathogenicity and the emergence of new virulence traits are lacking. Such limitations are partly due to the obligate biotrophic lifestyle of P. coronata f. sp. avenae as well as the dikaryotic nature of the genome, features that are also shared with other important rust pathogens. This study reports the first release of a haplotype-phased genome assembly for a dikaryotic fungal species and demonstrates the amenability of using emerging technologies to investigate genetic diversity in populations of P. coronata f. sp. avenae.

Reactions of eastern Canada oat genotypes to Puccinia coronata f. sp. avenae

2020 ◽  
Vol 100 (2) ◽  
pp. 209-217
Author(s):  
Allen G. Xue ◽  
Jim Menzies ◽  
Yuanhong Chen ◽  
Weikai Yan ◽  
Bao-luo Ma ◽  
...  
Keyword(s):  
Natural Populations ◽  
Field Trials ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
Adult Plant ◽  
Limiting Factor ◽  
Sources Of Resistance ◽  
Eastern Canada ◽  
Breeding Programs ◽  
Breeding Lines

Crown rust, caused by Puccinia coronata f. sp. avenae (Pca), is the most important disease and yield limiting factor of oat production in eastern Canada. In this study 101 oat genotypes composed of 51 cultivars and 50 breeding lines from eight oat breeding programs across Canada were evaluated for seedling reactions to six common Pca races, as well as reactions to a bulk inoculum of Pca in greenhouse trials and for adult plant resistance (APR) to natural populations of Pca in field trials in 2014 and 2015. Sixty-six genotypes showed resistant reactions to at least one of the six races; of these, 22 were resistant to all six races. These 22 genotypes also showed resistance to the bulk inoculum at the seeding stage and to the natural populations of Pca at the adult plant stage, suggesting that these current and future oat varieties have effective resistance against the common races and Pca populations in the region. Eleven genotypes, including 12ANS03, AAC Bullet, CFA1213, CFA1306, Idaho, OA1301-1w-3, OA1369-5, OA1370-2, OA1371-2, OA1383-2, and Oscar, were susceptible as seedlings but resistant as adult plants. APR is proven to be long lasting and provides broad-spectrum resistance to Pca populations. The 11 oat genotypes identified with APR in the present study are more desirable as sources of resistance for breeding programs developing durable crown rust resistant cultivars for eastern Canada.

INHERITANCE OF CROWN RUST RESISTANCE GENES IN AVENA STERILIS COLLECTIONS FROM ISRAEL, PORTUGAL, AND TUNISIA

1971 ◽  
Vol 13 (2) ◽  
pp. 251-255 ◽  
Author(s):  
G. Fleischmann ◽  
R. I. H. McKenzie ◽  
W. A. Shipton
Keyword(s):  
Resistance Genes ◽  
Rust Resistance ◽  
Dominant Gene ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
Avena Sterilis ◽  
Wild Oats ◽  
Puccinia Coronata Avenae ◽  
Dominant Genes ◽  
Rust Resistance Genes

The inheritance of genes in three collections of Avena sterilis wild oats conferring resistance to races 216, 264, 295, 305, 326, 330, 332, and 446 of crown rust, Puccinia coronata avenae, was investigated. C. I. 8081 from Portugal contained a partially dominant gene, designated Pc47, which conferred resistance to all eight races. CW486 from Tunisia had a dominant gene, designated Pc50, which gave resistance to all races except 295, 326, and 446. F158 from Israel had two dominant genes; one, designated Pc48, conferred resistance to all the races but 305, while the second, designated Pc49, conferred resistance to races 216, 326, 330, 332, and 446. Genes Pc47, Pc48, Pc49, and Pc50 were inherited independently of each other and of those genes previously isolated from A. sterilis.

scholarly journals Characteristics of Resistance to Puccinia coronata f. sp. avenae in Avena fatua

Plant Disease ◽  
2018 ◽  
Vol 102 (12) ◽  
pp. 2616-2624 ◽  
Author(s):  
Edyta Paczos-Grzeda ◽  
Sylwia Sowa ◽  
Aneta Koroluk ◽  
Tim Langdon
Keyword(s):  
Resistance Genes ◽  
Rust Resistance ◽  
The United States ◽  
Avena Fatua ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
United States Department ◽  
Seedling Resistance ◽  
Infection Pattern ◽  
Crown Rust Resistance

Crown rust, caused by Puccinia coronata f. sp. avenae, is the most widespread and harmful fungal disease of oat. The best defense against the pathogen is use of cultivars with genetic resistance, which is effective, economic, and an environmentally friendly alternative to chemical control. However, the continuous evolution of the pathogen can rapidly overcome major gene resistance, creating an urgent need to identify new sources. Wild oat accessions have already proven to be valuable donors of many resistance genes, but the weed species Avena fatua remains underexploited. Its abundance across multiple environments and the frequent occurrence of herbicide-resistant populations demonstrate its ready ability to adapt to biotic and abiotic stresses; yet, surprisingly, there are no extensive studies which describe crown rust resistance occurrence in gene bank stocks of A. fatua. In this study, 204 accessions of A. fatua maintained in the collections of the United States Department of Agriculture (USDA) and Polish National Centre for Plant Genetic Resources were evaluated at the seedling stage for crown rust reaction using host–pathogen tests with five highly diverse and virulent races of P. coronata. Of tested genotypes, 85% showed a heterogeneous infection pattern, while 61% were susceptible or moderately susceptible to all races. Of the 79 resistant A. fatua accessions, seedling resistance to at least two P. coronata isolates was recognized within 19 accessions, with 13 displaying a homogeneously resistant phenotype to one or two races. Accessions showing multiple single seedling resistance to three or four isolates were observed. Based on the seedling reaction to isolates used in the study, 18 infection profiles (IP) were determined. Using UPGMA clustering, resistant accessions were divided into six main clusters encompassing samples with similar IPs. Twelve of 18 patterns allowed us to postulate the likely presence of novel crown rust resistance genes, whose origin was predominantly from Kenya or Egypt. Future work will clarify the genetic basis of the resistances observed here, as well as confirm their potential utility in breeding resistant oat cultivars.

scholarly journals Crown rust pathotypes determined on oats in the Czech Republic from 2004 to 2006 and reaction to oat cultivars

2008 ◽  
Vol 44 (No. 2) ◽  
pp. 60-65 ◽  
Author(s):  
H. Jiráková ◽  
A. Hanzalová
Keyword(s):  
Czech Republic ◽  
Resistance Genes ◽  
Virulence Genes ◽  
Resistance Breeding ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
The Czech Republic ◽  
Oat Crown Rust ◽  
Oat Cultivars ◽  
High Diversity

The incidence of oat crown rust (Puccinia coronata var. avenae Fraser et Ledingham) pathotypes was recorded in the Czech Republic in 2004–2006. The virulence of collected 79 monopustule oat crown rust isolates was assessed on 23 differentials. High diversity was observed; the isolates possessed from 0 to 8 virulence genes. More than 80% of pathotypes were recorded only once. Pathotypes BLBG and BLBC were the most frequent. None of the tested isolates was virulent to resistance genes Pc39, Pc50, Pc52, Pc59, Pc62 and Pc68. Registered cultivars Avenuda, Dalimil, Auron, Isak were susceptible to the majority of pathotypes, cvs. Abel, Ardo, Atego, Azur, Neklan, Radius and Saul to all used pathotypes. Only the Czech cultivar Vok was resistant to all but four used pathotypes. Acquired data are useful for resistance breeding.

scholarly journals Pathogenic Variability of Puccinia coronata f. sp. avenae and P. graminis f. sp. avenae on Oat in South Africa

Plant Disease ◽  
2001 ◽  
Vol 85 (10) ◽  
pp. 1085-1090 ◽  
Author(s):  
B. D. van Niekerk ◽  
Z. A. Pretorius ◽  
W. H. P. Boshoff
Keyword(s):  
South Africa ◽  
Resistance Gene ◽  
Resistance Genes ◽  
Stem Rust ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
Puccinia Graminis ◽  
Wild Oat ◽  
Low Frequencies ◽  
Pathogenic Variability

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, OX88I 075-106, Sederberg, and W94/4; Pg2 and/or Pg4 in Euro, Perdeberg, Potberg, and Swartberg; and Pg9 in Pallinup and Victorian. Collections of wild oat species Avena fatua, A. byzantina, A. sterilis, and A. barbata were susceptible to all crown rust patho-types, while the four stem rust pathotypes were virulent on all species except A. barbata.

scholarly journals De novo assembly and phasing of dikaryotic genomes from two isolates of Puccinia coronata f. sp. avenae, the causal agent of oat crown rust

2017 ◽  
Author(s):  
Marisa E. Miller ◽  
Ying Zhang ◽  
Vahid Omidvar ◽  
Jana Sperschneider ◽  
Benjamin Schwessinger ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
De Novo ◽  
Rust Fungus ◽  
Expression Patterns ◽  
Haplotype Diversity ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
Small Subset ◽  
Nucleotide Polymorphisms ◽  
Oat Crown Rust

AbstractOat crown rust, caused by the fungus Puccinia coronata f. sp. avenae (Pca), is a devastating disease that impacts worldwide oat production. For much of its life cycle, Pca is dikaryotic, with two separate haploid nuclei that may vary in virulence genotype, highlighting the importance of understanding haplotype diversity in this species. We generated highly contiguous de novo genome assemblies of two Pca isolates, 12SD80 and 12NC29, from long-read sequences. In total, we assembled 603 primary contigs for a total assembly length of 99.16 Mbp for 12SD80 and 777 primary contigs with a total length of 105.25 Mbp for 12NC29, and approximately 52% of each genome was assembled into alternate haplotypes. This revealed structural variation between haplotypes in each isolate equivalent to more than 2% of the genome size, in addition to about 260,000 and 380,000 heterozygous single-nucleotide polymorphisms in 12SD80 and 12NC29, respectively. Transcript-based annotation identified 26,796 and 28,801 coding sequences for isolates 12SD80 and 12NC29, respectively, including about 7,000 allele pairs in haplotype-phased regions. Furthermore, expression profiling revealed clusters of co-expressed secreted effector candidates, and the majority of orthologous effectors between isolates showed conservation of expression patterns. However, a small subset of orthologs showed divergence in expression, which may contribute to differences in virulence between 12SD80 and 12NC29. This study provides the first haplotype-phased reference genome for a dikaryotic rust fungus as a foundation for future studies into virulence mechanisms in Pca.ImportanceDisease management strategies for oat crown rust are challenged by the rapid evolution of Puccinia coronata f. sp. avenae (Pca), which renders resistance genes in oat varieties ineffective. Despite the economic importance of understanding Pca, resources to study the molecular mechanisms underpinning pathogenicity and emergence of new virulence traits are lacking. Such limitations are partly due to the obligate biotrophic lifestyle of Pca as well as the dikaryotic nature of the genome, features that are also shared with other important rust pathogens. This study reports the first release of a haplotype-phased genome assembly for a dikaryotic fungal species and demonstrates the amenability of using emerging technologies to investigate genetic diversity in populations of Pca.

Application of an osmium-maceration technique to observe plant–microbe interfaces of Italian ryegrass and crown rust fungi by scanning electron microscopy

1992 ◽  
Vol 70 (2) ◽  
pp. 438-442 ◽  
Author(s):  
Hironori Koga ◽  
Takao Tsukiboshi ◽  
Tsutomu Uematsu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Rust Fungus ◽  
Three Dimensional ◽  
Crown Rust ◽  
Italian Ryegrass ◽  
Puccinia Coronata ◽  
Cytoplasmic Matrix ◽  
Three Dimensional Configuration ◽  
Scanning Electron

The osmium-maceration technique (osmium–DMSO–osmium method) was used to observe intracellular structures of Italian ryegrass leaves infected with crown rust fungus (Puccinia coronata Corda var. coronata) by scanning electron microscopy. Prolonged maceration with dilute osmium removed the cytoplasmic matrix, and intracellular structures were disclosed in a bold relief. The three-dimensional configuration of nuclei, mitochondria, the endoplasmic reticulum, and other structures of host and parasite cells were visible. Key words: scanning electron microscopy (SEM), osmic maceration, intracellular structure, Puccinia coronata, Italian ryegrass.

Sign in / Sign up

Export Citation Format

Share Document