| incidence of serum precipitins against organic-dust antigens in different populations by counterimmunoelectrophoresis. | the incidence of serum antidust and antifungal precipitins was determined by counterimmunoelectrophoresis in 317 atopic and nonatopic subjects of three geographic areas (north central, southern, and western united states). the selected lyophilized crude antigens employed were from house dust, micropolyspora faeni, candida albicans, alternaria tenuis, aspergillus fumigatus, puccinia coronata, cantharellus cibarius, and amborsia trifida. antidust precipitins were detected with high frequency in at ... | 1975 | 1192851 |
| qualitative and quantitative trait loci conditioning resistance to puccinia coronata pathotypes nqmg and lgcg in the oat (avena sativa l.) cultivars ogle and tam o-301. | mapping disease resistance loci relies on the type and precision of phenotypic measurements. for crown rust of oat, disease severity is commonly assessed based on visual ratings of infection types (it) and/or diseased leaf area (dla) of infected plants in the greenhouse or field. these data can be affected by several variables including; (i) non-uniform disease development in the field; (ii) atypical symptom development in the greenhouse; (iii) the presence of multiple pathogenic races or pathot ... | 2008 | 18193188 |
| heterothallism in puccinia coronata. | | 1930 | 17801368 |
| consistent detection of qtls for crown rust resistance in italian ryegrass (lolium multiflorum lam.) across environments and phenotyping methods. | crown rust, caused by puccinia coronata f. sp. lolii, is one of the most important diseases of temperate forage grasses, such as ryegrasses (lolium spp.), affecting yield and nutritional quality. therefore, resistance to crown rust is a major goal in ryegrass breeding programmes. in a two-way pseudo-testcross population consisting of 306 lolium multiflorum individuals, multisite field evaluations as well as alternative methods based on artificial inoculation with natural inoculate in controlled ... | 2007 | 17426957 |
| resistance to rust fungi in lolium perenne depends on within-species variation and performance of the host species in grasslands of different plant diversity. | the hypothesis that plant species diversity and genetic variation of the host species decrease the severity of plant diseases is supported by studies of agricultural systems, but experimental evidence from more complex systems is scarce. in an experiment with grassland communities of varying species richness (1, 2, 4, 8, 16, and 60 species) and functional group richness (1, 2, 3, and 4 functional groups), we used different cultivars of lolium perenne (perennial ryegrass) to study effects of biod ... | 2007 | 17415594 |
| pathogenic fungal species isolated from leaves and seeds of smooth brome (bromus inermis leyss.). | authors made mycological investigations on smooth brome (bromus inermis leyss.) cultivar 'k51'. during the vegetation period presence and dominance of fungal species were revealed and seed infection rates were tested in two winter season. puccinia recondita, puccinia coronata, stagnospora bromi and drechslera dictyoides were dominated on the leaves, but saprotrophic fungal genera (alternaria, epicoccum, cladosporium, pithomyces) were also identified. considerable rate of seed infection were obse ... | 2006 | 17390865 |
| microsatellite variation in avena sterilis oat germplasm. | the avena sterilis l. collection in the plant gene resources of canada (pgrc) consists of 11,235 accessions originating from 27 countries and is an invaluable source of genetic variation for genetic improvement of oats, but it has been inadequately characterized, particularly using molecular techniques. more than 35 accessions have been identified with genes for resistance to oat crown and stem rusts, but little is known about their comparative genetic diversity. this study attempted to characte ... | 2007 | 17265024 |
| breeding for disease resistance in the major cool-season turfgrasses. | over the past several decades, breeding cool-season turfgrasses for improved disease resistance has been the focus of many turfgrass breeding programs. this review article discusses the dramatic improvements made in breeding kentucky bluegrass (poa pratensis) for resistance to leaf spot (caused by drechslera poae), stem rust (caused by puccinia graminis), and stripe smut (caused by ustilago striiformis); perennial ryegrass (lolium perenne) for resistance to gray leaf spot (caused by pyricularia ... | 2006 | 17061916 |
| genetic diversity in the mycoparasite sphaerellopsis filum inferred from aflp analysis and its-5.8s sequences. | genetic diversity among 51 isolates of the mycoparasite sphaerellopsis filum from melampsora rusts on willow and poplar was examined using aflp. genetic variation was relatively low among the isolates (nei & li's similarities > or =90). genetic diversity calculated using shannon index was 0.119 at loughgall, northern ireland, 0.109 at markington, northern england, 0.039 at craibstone, scotland, and 0.015 at long ashton, southwest england. at long ashton, 14 out of 16 isolates shared the same afl ... | 2006 | 17020805 |
| development and characterization of est-ssr markers for the crown rust pathogen of ryegrass (puccinia coronata f.sp. lolii). | the causative organism of crown rust in ryegrasses (puccinia coronata f.sp. lolii) is an obligate biotroph that causes significant economic losses within the temperate grazing industries of dairy, meat, and wool production. this study reports on the development, transferability, and utility of gene-associated simple sequence repeat (ssr) molecular markers for crown rust. analysis of 1,100 expressed sequence tag (est) sequences from a urediniospore-derived cdna library detected 55 ssr loci. the m ... | 2006 | 16936837 |
| effect of cations on germination & germ tube development of puccinia coronata uredospores. | | 1961 | 16655462 |
| spore dimensions of puccinia species of cereal hosts as determined by image analysis. | digital image analysis was used to measure dimensions of spores produced by puccinia coronata, p. graminis, p. hordei, p. recondita, p. striiformis and p. triticina. included were teliospores, basidiospores, urediniospores and, except for p. striiformis, pycniospores and aeciospores. length, width and projection area of spores were measured with nih image or scion software. by using limits on size, spores were automatically selected and measured, except for teliospores, which required manual eli ... | 2005 | 16396355 |
| four qtls determine crown rust (puccinia coronata f. sp. lolii) resistance in a perennial ryegrass (lolium perenne) population. | crown rust resistance is an important selection criterion in ryegrass breeding. the disease, caused by the biotrophic fungus puccinia coronata, causes yield losses and reduced quality. in this study, we used linkage mapping and qtl analysis to unravel the genomic organization of crown rust resistance in a lolium perenne population. the progeny of a pair cross between a susceptible and a resistant plant were analysed for crown rust resistance. a linkage map, consisting of 227 loci (aflp, ssr, rfl ... | 2005 | 16118663 |
| quantitative trait loci for partial resistance to crown rust, puccinia coronata, in cultivated oat, avena sativa l. | to facilitate the detection of quantitative trait loci (qtls) for partial resistance to oat crown rust, puccinia coronata f. sp. avenae eriks., a genetic map was generated in a population of 158 f(6)-derived oat recombinant inbred lines from a cross of a partial resistance line mn841801-1 by a susceptible cultivar selection 'noble-2'. the map, developed using 230 marker loci, mostly restriction fragment length polymorphism and amplified fragment length polymorphism markers, spanned 1,509 cm (hal ... | 2005 | 15918009 |
| increased resistance to crown rust disease in transgenic italian ryegrass (lolium multiflorum lam.) expressing the rice chitinase gene. | we introduced the rice chitinase (cht-2; rcc2) gene into calli of italian ryegrass (lolium multiflorum lam.), with a hygromycin phosphotransferase (hpt) gene as a selectable marker, by particle bombardment. hygromycin-resistant calli were selected and transferred to regeneration medium for shoot formation. polymerase chain reaction (pcr) analysis revealed regenerants containing the hpt gene. the rcc2 gene was detected in 65.5% of those regenerants. southern hybridization detected both hpt and rc ... | 2004 | 15599752 |
| development and characterization of novel, polymorphic microsatellite markers for oat crown rust, puccinia coronata. | we report the development of 37 novel and polymorphic microsatellite markers for oat crown rust, puccinia coronata f.sp. avenae. the allelic diversity ranged from two to 16 alleles per locus. observed heterozygosity ranged from 0.000 to 0.971, and expected heterozygosity from 0.057 to 0.848. thirteen of the loci were not in hardy-weinberg equilibrium, due to either the presence of null alleles, small sample size, or the effects of population subdivision (wahlund's effect). all 37 primer pairs we ... | 2008 | 21586056 |
| nitric oxide and reactive oxygen species do not elicit hypersensitive cell death but induce apoptosis in the adjacent cells during the defense response of oat. | nitric oxide (no) acts as a signaling molecule in many cellular responses in plants and animals. oat plants (avena sativa l.) evoke the hypersensitive response (hr), which shares morphological and biochemical features with mammalian apoptosis, such as dna laddering and heterochromatin condensation, in response to the avirulent crown rust fungus (puccinia coronata f. sp. avenae). we examined the role of no and reactive oxygen species (ros) in the initiation of hypersensitive cell death, which is ... | 2004 | 15000391 |
| analysis of the involvement of hydroxyanthranilate hydroxycinnamoyltransferase and caffeoyl-coa 3-o-methyltransferase in phytoalexin biosynthesis in oat. | two oat genes encoding hydroxycinnamoyl-coa:hydroxyanthranilate n-hydroxycinnamoyltransferase (hht) and s-adenosyl-l-methionine:trans-caffeoyl-coa 3-o-methyltransferase (ccoaomt), both of which are possibly involved in the biosynthesis of oat avenanthramide phytoalexins, were cloned and their expression profiles in response to biological stress were studied. four distinct cdnas of oat hht (ashht1-4) were isolated with the degenerative polymerase chain reaction method. the enzymatic activity of a ... | 2004 | 14714871 |
| introgression of crown rust (puccinia coronata) resistance from meadow fescue (festuca pratensis) into italian ryegrass (lolium multiflorum) and physical mapping of the locus. | resistance was found in the meadow fescue (festuca pratensis) to crown rust (puccinia coronata), originating from ryegrasses (lolium spp). a backcrossing programme successfully transferred this resistance into diploid italian ryegrass (lolium multiflorum) and genomic in situ hybridisation (gish) was used to identify the introgressed fescue chromosome segment. the resistant (r) plants in two bc3 lines all carried an introgressed segment on a single chromosome, which in one of the lines was confin ... | 2003 | 14512955 |
| apoptotic cell death is a common response to pathogen attack in oats. | we have examined the characteristics of cell death induced by pathogen infection in oats with respect to following hallmark apoptotic features: dna laddering, chromatin condensation, and electron microscopic-terminal deoxynucleotidyl transferase-mediated utp end labeling positive response. a wide range of plant pathogens representing different levels of parasitism in susceptible and resistant interactions were used for the inocula, which include (i) an obligate parasite, puccinia coronata f. sp. ... | 2002 | 12437297 |
| genetic and physical mapping of lrk10-like receptor kinase sequences in hexaploid oat (avena sativa l.). | oat receptor-like kinase gene sequences, homologous to the lrk10 gene from wheat (triticum aestivum l.), were mapped in oat (avena sativa l.). pcr primers designed from the wheat lrk10 were used to produce alrk10 from oat. two dna sequences, alrk1a1 and alrk4a5, were produced from primers designed from coding and noncoding regions of alrk10. their use as rflp probes indicated that the kinase genes mapped to four loci on different hexaploid oat 'kanota' x 'ogle' linkage groups (4_12, 5, 6, and 13 ... | 2002 | 11908651 |
| oare-1, a ty1-copia retrotransposon in oat activated by abiotic and biotic stresses. | transcriptionally active ty1-copia ltr-retrotransposons were found in oat using rt-pcr for amplifying the reverse transcriptase domain. sequence analysis of the rt-pcr clones suggested that oat ltr-retrotransposons consist of at least seven groups, which were tentatively designated as oatrt1 to oatrt7. a full length copy of oatrt1 was isolated from an oat genomic library, and was designated oare-1. oare-1 was 8,665 bp long and a member of the bare-1 subgroup. the oat genome carried it in multipl ... | 2001 | 11773527 |
| rds and rih mediate hypersensitive cell death independent of gene-for-gene resistance to the oat crown rust pathogen puccinia coronata f. sp. avenae. | the pca crown rust resistance cluster in the diploid avena genus confers gene-for-gene specificity to numerous isolates of puccinia coronata f. sp. avenae. recombination breakpoint analysis indicates that specificities conferred by the pca cluster are controlled by at least five distinct genes, designated pc81, pc82, pc83, pc84, and pc85. avena plants with the appropriate genotype frequently respond to p. coronata by undergoing hypersensitive cell death at the sites of fungal infection. autofluo ... | 2001 | 11768532 |
| inheritance of resistance in smooth bromegrass to the crown rust fungus. | common smooth bromegrass (bromus inermis leyss.) is octoploid, 2n = 8x = 56, with a genome structure of aaaab1b1b2b2. tetrasomic inheritance patterns have been observed in smooth bromegrass, but disomic inheritance is also expected from cytologic observations. smooth bromegrass is susceptible to the crown rust fungus (puccinia coronata corda.). the objective of this study was to determine the inheritance of smooth bromegrass resistance to p. coronata. seven smooth bromegrass clones, three suscep ... | 2000 | 11218086 |
| identification of the 100-kd victorin binding protein from oats. | the fungus cochliobolus victoriae, the causal agent of victoria blight of oats, produces the host-specific toxin victorin. sensitivity of oats to victorin, and thus susceptibility to the fungus, is controlled by a single dominant gene. this gene is believed to also confer resistance to the crown rust pathogen puccinia coronata. in the case of victoria blight, the gene has been hypothesized to condition susceptibility by encoding a toxin receptor. a 100-kd victorin binding protein (vbp) has been ... | 1994 | 7919984 |
| comparative analysis of multiple disease resistance in ryegrass and cereal crops. | ryegrass (lolium spp.) is among the most important forage crops in europe and australia and is also a popular turfgrass in north america. previous genetic analysis based on a three-generation interspecific (l. perennexl. multiflorum) ryegrass population identified four quantitative trait loci (qtls) for resistance to gray leaf spot (magneporthe grisea) and four qtls for resistance to crown rust (puccinia coronata). the current analysis based on the same mapping population detected seven qtls for ... | 2008 | 18521564 |
| molecular mapping of the crown rust resistance gene rpc1 in barley. | abstract crown rust of barley, caused by puccinia coronata var. hordei, occurs sporadically and sometimes may cause yield and quality reductions in the great plains region of the united states and canada. the incompletely dominant resistance allele rpc1 confers resistance to p. coronata in barley. two generations, f(2) and f(2:3), developed from a cross between the resistant line hor2596 (ciho 1243) and the susceptible line bowman (pi 483237), were used in this study. bulked segregant analysis c ... | 2004 | 18943106 |
| quantitative trait loci associated with seedling resistance to isolates of puccinia coronata in oat. | abstract in our previous report, quantitative trait loci (qtl) for field adult plant resistance to crown rust were identified in an oat population of 152 f(5:6) recombinant inbred lines from the cross of 'ogle' (susceptible)/mam17-5 (resistant). the objectives of the present study were to identify in the same population, the number, genomic location, and effect of qtl and digenic qtl epistasis associated with greenhouse seedling resistance to isolates of puccinia coronata to determine if the qtl ... | 2003 | 18943167 |
| mapping and comparative analysis of qtl for crown rust resistance in an italian x perennial ryegrass population. | abstract crown rust (puccinia coronata f. sp. lolli) is a serious fungal foliar disease of perennial ryegrass (lolium perenne l.) and italian ryegrass (l. multiflorum lam.), which are important forage and turf species. a number of quantitative trait loci (qtl) for crown rust resistance previously were identified in perennial ryegrass under growth chamber or greenhouse conditions. in this study, we conducted a qtl mapping for crown rust resistance in a three-generation italian x perennial ryegras ... | 2007 | 18943608 |
| patterns of virulence in natural populations of puccinia coronata on wild oat in israel and in agricultural populations on cultivated oat in the united states. | abstract crown rust (puccinia coronata) in indigenous populations of avena sterilis has been cited as an example of stability of wild pathosystems that consist of natural mixtures of resistance and virulence. this study confirmed that virulence/avirulence polymorphisms in p. coronata on a. sterilis in israel are highly diverse and that super races do not dominate. isolates of p. coronata from israel in 1991 to 1996 were polymorphic for virulence to 35 of 36 differential oat lines with resistance ... | 2004 | 18943770 |
| virulence associations in oat crown rust. | abstract isolates of puccinia coronata obtained from natural populations of avena sterilis in israel, winter oat (a. sativa) cultivars in texas, and spring oat cultivars in the northern plains states of minnesota, north dakota, and south dakota were analyzed for significance of pairwise virulence associations. isolates from all three regions were tested on 25 oat lines with single p. coronata (pc) genes for crown rust resistance from a. sterilis and one line with a pc gene from a. sativa. isolat ... | 2005 | 18943836 |
| characterization and mapping of oat crown rust resistance genes using three assessment methods. | abstract resistance is the primary means of control for crown rust of oat (avena sativa l.), caused by puccinia coronata f. sp. avenae, and better knowledge of the genetics of resistance will enhance resistance breeding. disease data were generated in the field and greenhouse for parents and recombinant inbred lines of the ogle/tam o-301 (ot) oat mapping population using (i) a new quantitative assay that employs quantitative real-time polymerase chain reaction (q-pcr) to estimate fungal growth i ... | 2007 | 18944171 |
| sources and genetics of crown rust resistance in barley. | abstract crown rust, caused by puccinia coronata var. hordei, is a new disease threat to barley in the great plains region of the united states. deployment of resistant cultivars is the only economically viable option for the control of this disease. thus, the objective of this study was to investigate the sources and genetics of crown rust resistance in barley. a geographically diverse sample of barley germ plasm collected around the world (526 accessions total) was evaluated at the seedling st ... | 2002 | 18944216 |
| restriction fragment length polymorphisms linked to genes for resistance to crown rust (puccinia coronata) in near-isogenic lines of hexaploid oat (avena sativa). | crown rust, perhaps the most important fungal disease of oat, is caused by puccinia coronata. an examination of near-isogenic lines (nils) of hexaploid oat (avena sativa) was conducted to identify markers linked to genes for resistance to crown rust. these lines were created such that a unique resistance gene is present in each of the two recurrent parent backgrounds. the six nils of the current study, x434-ii, x466-i, and y345 (recurrent parent c237-89) and d486, d494, and d526 (recurrent paren ... | 1994 | 18470125 |
| placement of loci for avenins and resistance to puccinia coronata to a common linkage group in avena strigosa. | alcohol-soluble seed storage proteins of oat (avenins) were extracted from two diploid accessions representing the a genome and separated by high-resolution acid polyacrylamide gel electrophoresis. polymorphisms were detected for three clearly resolved protein bands. linkage analysis of 88 f2:3 families mapped the three bands to a single locus. integration of avenin segregation data with an rflp linkage map constructed from the same population, mapped the avenin locus to a linkage group containi ... | 1994 | 18470133 |
| transferability of ssr markers from related uredinales species to the coffee rust hemileia vastatrix. | the aim of the present research was to test the transferability of simple sequence repeat (ssr) markers developed in two uredinales species to hemileia vastatrix, coffee rust. the development of efficient techniques for the identification of h. vastatrix isolates is imperative, given the continuous development of new races. the transferability of 25 ssr markers developed in the related uredinales species puccinia coronata f. sp lolli and melampsora linii to h. vastatrix was tested. a low level o ... | 2008 | 19048497 |
| demonstration of pathotype specificity in stem rust of perennial ryegrass. | rust diseases cause significant damage in forage and seed crops of perennial ryegrass (lolium perenne), which is highly heterozygous and heterogeneous and thus presents difficulty in genetic analysis. there has been no definitive demonstration of the existence of pathotypes for stem rust or other rusts of perennial ryegrass, although experiments with crown rust (puccinia coronata) of this host are strongly suggestive of pathotype specificity. we made single-pustule isolates of p. graminis subsp. ... | 2009 | 19740032 |
| mapping of sts markers obtained from oat resistance gene analog sequences. | two previously isolated resistance gene analogs (rgas) of oat have been located as rflps in the reference map of avena byzantina 'kanota' x avena sativa 'ogle' in regions either homologous or homoeologous to loci for resistance to puccinia coronata, the causal agent of crown rust. in this study, the rgas were mapped in two recombinant inbred line (ril) populations that segregate for crown rust resistance: the diploid avena strigosa x avena wiestii ril population (asw), which has been used for ma ... | 2009 | 19767892 |
| quantitative trait loci in the ogle/tam o-301 oat mapping population controlling resistance to puccinia coronata in the field. | crown rust is the most damaging disease of cultivated oat (avena sativa) and genetic resistance is the primary means of controlling the disease. quantitative trait loci (qtl) with major and minor effects have been identified in ogle1040 and tam o-301 (most notably, pc58 and pcnqmg/lgcg from tam o-301 and ot-27 from ogle1040) through single-isolate greenhouse and field tests. to map loci and determine the effectiveness of previously identified qtl against naturally occurring pathogen populations ... | 2010 | 20373970 |
| mapping of the oat crown rust resistance gene pc91. | crown rust is an important disease of oat caused by puccinia coronata corda f. sp. avenae eriks. crown rust is efficiently and effectively managed through the development of resistant oat varieties. pc91 is a seedling crown rust resistance gene that is highly effective against the current p. coronata population in north america. the primary objective of this study was to develop dna markers linked to pc91 for purposes of marker-assisted selection in oat breeding programs. the pc91 locus was mapp ... | 2011 | 20862449 |
| self-fertility and other distinguishing characteristics of a new morphotype of puccinia coronata pathogenic on smooth brome grass. | a new morphotype of puccinia coronata, pathogenic to bromus inermis, a common roadside and pasture grass in the northern united states, was discovered in the 1990s and described as p. coronata f. sp. bromi by delgado et al in 2001. puccinia coronata f. sp. bromi does not require fertilization of pycnia to produce aecia on its alternate host, whereas fertilization is required in all other varieties or formae speciales of p. coronata with aecial hosts in the family rhamnaceae and for which life cy ... | 2003 | 21156592 |
| consistency of crown rust evaluation in ryegrass cultivars. | crown rust (puccinia coronata) is the most important leaf disease in forage ryegrasses (lolium spp.). in order to evaluate the stability in space and time of crown rust resistance a multisite rust evaluation trial was established by the european breeders association eucarpia ( fodder crops section). the same seed lots of 33 perennial ryegrass (lolium perenne) and 18 italian ryegrass (lolium multiflorum) varieties were sown in april 2001, 2004 and 2007 at 27 european sites. this paper reports the ... | 2010 | 21534471 |