A single-spore analysis of rust pustules produced by mixing isolates of two races of Puccinia coronata var. avenue

1968 ◽  
Vol 46 (11) ◽  
pp. 1455-1458
Author(s):  
A. Dinoor ◽  
J. Khair ◽  
G. Fleischmann
Keyword(s):  
Infection Type ◽  
The Other ◽  
Puccinia Coronata ◽  
Masking Effect ◽  
Single Spore ◽  
New Race ◽  
Infection Types ◽  
Differential Varieties ◽  
Parent Race

Urediospores of pairs of isolates of Puccinia coronata var. avenae were simultaneously inoculated side by side on a susceptible oat leaf to produce a common pustule. The infection types of the culture from the single pustule, and from single-spore isolates of the pustule, were determined on key differential varieties distinguishing the component biotypes. The composition of the pustule was found to vary with the component races involved, and among pustules established from the same components.One pair of component races produced pustules which were phenotypically like one or the other of the isolates used in the mixture. Single-spore isolates from these pustules gave the same infection type as the pustule from which they were isolated, indicating that either one isolate alone produced the pustule, or that it predominated in what would then be a compound pustule.Another pair produced infection types unlike those of either parent race, and thus behaved phenotypically as a new race on the differential varieties. However, single-spore isolates from such pustules behaved as one or the other of the components. The masking effect of virulence over avirulence was also demonstrated by single-spore analysis of these compound pustules.

scholarly journals A New Race of Pyrenophora tritici-repentis from Brazil

Plant Disease ◽  
2002 ◽  
Vol 86 (9) ◽  
pp. 1050-1050 ◽  
Author(s):  
S. Ali ◽  
L. J. Francl
Keyword(s):  
Tan Spot ◽  
The Other ◽  
Single Spore ◽  
Pyrenophora Tritici Repentis ◽  
Differential Set ◽  
Race 1 ◽  
Plant Pathol ◽  
Wheat Leaves ◽  
New Race ◽  
Wheat Lines

Pyrenophora tritici-repentis causes tan spot of wheat worldwide. Fungal isolates have been characterized into seven races based on their ability to induce necrosis and chlorosis on appropriate wheat differentials (1,2). Nineteen single-spore isolates of P. tritici-repentis were recovered from diseased wheat leaves collected from Brazil. The isolates were tested for their race structure by individually inoculating a suspension of 3,000 conidia per ml on wheat differential seedlings at the 2-leaf stage in the greenhouse. The isolates were tested three times and consistent results were found. The differential set was comprised of Glenlea, Katepwa, ND495, 6B365, Salamouni, and M-3. Seven of the 19 isolates were grouped into race 1 because they produced necrosis on Glenlea, Katepwa, and ND495; chlorosis on 6B365; and neither symptom on Salamouni and M-3. Twelve of the isolates produced necrosis on Glenlea, Katepwa, ND495, 6B365, and Salamouni, and neither symptom on M-3. Necrotic reactions to these isolates on 6B365 (chlorotic or resistant to currently identified 7 races) and Salamouni (resistant to all 7 races), and the resistant reaction on M-3 (resistant to all 7 races) differentiate them from the other seven races. Therefore, we grouped these isolates under a new race and designated this as race 8. To our knowledge, this is the first report on the occurrence of race 8 in P. tritici-repentis. This discovery holds particular significance to breeders and pathologists interested in producing wheat lines with resistance to tan spot. Additionally, we suggest that M-3 be added to the differential set because this line is resistant to all eight identified races. More isolates from Brazil are under investigation to discover the P. tritici-repentis race structure in the country. References: (1) S. Ali et al. (Abstr.) Phytopathology 92(suppl):S3, 2002. (2) S. E. Strelkov et al. Can. J. Plant Pathol. 24:29, 2002.

INHERITANCE OF PATHOGENICITY AND UREDIOSPORE COLOR IN CROSSES BETWEEN PHYSIOLOGIC RACES OF OAT STEM RUST

1949 ◽  
Vol 27c (5) ◽  
pp. 203-217 ◽  
Author(s):  
T. Johnson
Keyword(s):  
Infection Type ◽  
Single Pair ◽  
Maternal Parent ◽  
Race 1 ◽  
Physiologic Races ◽  
Infection Types ◽  
Orange Color ◽  
Parent Race

In the F1 generation of crosses between physiologic races 7 (orange) and 11 (red) of Puccinia graminis Pers. var. Avenae Erikss. and Henn., the medium sized uredia (type 2 infection) formed by race 11 on the oat variety White Tartar were dominant to the large (type 4) uredia of race 7, and the small (type 1) uredia of race 7 on the variety Richland were dominant to the type 4 uredia formed by race 11. On the varieties Sevnothree and Joanette Strain, the F1 hybrids produced the same type of infection as did the "maternal" parent race, that is, hybrids from race 7 × race 11 crosses produced a type 4 infection like race 7, and reciprocal hybrids produced a type 1 infection like race 11. These facts led to the suggestion that the cytoplasm of the maternal parent race influenced the infection type of the F1 hybrid on these two oat varieties.A study of the F2 generation of the cross race 11 × race 7 showed that on the varieties White Tartar and Richland the dominant and recessive infection types appeared in a ratio of 9:7, which suggests that their inheritance is governed by two pairs of complementary genes. The distribution of physiologic races in F2 conforms to this assumption and indicates that the genes governing infection types on these two varieties associate at random to produce physiologic races 1, 11, 3, and 4. These races occurred in F2 in a ratio of 31: 20: 22: 12, as compared to an expected ratio of 27: 21: 21: 16. On the variety Sevnothree, 84 of 85 F2 cultures produced type 1 uredia, in this way resembling the maternal parent, race 1, and the maternal grandparent, race 11. One F2 culture, only produced the type 4 uredia characteristic of the paternal grandparent, race 7. It is concluded from this study, and from crosses between races 1 and 2, that the maternal (cytoplasmic) influence evidenced in the F1 generation persists m F2 and F3.In F1, the red urediospore color of race 11 was dominant to the orange color of race 7. The distribution in these two color classes in F2 and F3 suggests that the inheritance of urediospore color is governed by a single pair of genes.

scholarly journals Fine Structure and Staining Behaviour of Heterochromatic Segments in Two Plants

1974 ◽  
Vol 14 (3) ◽  
pp. 505-521
Author(s):  
L. F. LACOUR ◽  
B. WELLS
Keyword(s):  
Fine Structure ◽  
Light Microscope ◽  
Mitotic Cycle ◽  
The Other ◽  
Masking Effect ◽  
Root Tips ◽  
Metaphase Chromosomes ◽  
Differential Reactivity ◽  
Scilla Sibirica ◽  
Electron Microscopes

With the use of the light and electron microscopes, the chromosomes of Fritillaria lanceolata and Scilla sibirica are shown to differ in respect of the heterochromatin they contain. In root meristems of the former, the heterochromatic regions (H-segments) were recognizable at all phases of the mitotic cycle by their slighter opacity to electrons than that of euchromatic parts. This was due both to less tight packing of the chromatin fibrils and lower opacity of the fibrils themselves, even though both had the same diameter, about 3 nm. In root tips of the Scilla, the heterochromatin was invariably of similar opacity to euchromatin and thus only recognizable at telophase and interphase as large chromocentres. The opacity to electrons in the heterochromatin of the 2 species, was at all times closely paralleled by the staining behaviour seen with the light microscope in sections (0.07-0.5 µm in thickness) stained with toluidine blue. The disparity in the Fritillaria, as seen in sections with the light microscope, in respect of the stainability of the hetero- and euchromatin, was masked in Feulgen squash preparations of root tips from plants grown at 18-20 °C; at metaphase by the thickness of the chromosomes and at interphase by the density of the chromocentres. When, on the other hand, the plants were grown for 4 days at 2 °C, the masking effect of thickness was circumvented in metaphase chromosomes by differential super-contraction in euchromatin. The implications of these findings in respect to previous interpretations of the differential reactivity of H-segments to low temperature, as well as the phenomenon of enhanced and reduced fluorescence in these segments with fluorochromes are discussed.

Abstract P190: Triggering of Coronary Heart Disease by Infection Type: The Atherosclerosis Risk in Communities Study

Circulation ◽  
2018 ◽  
Vol 137 (suppl_1) ◽  
Author(s):  
Logan Cowan ◽  
Pamela Lutsey ◽  
Jim Pankow ◽  
Kunihiro Matsushita ◽  
Junichi Ishigami ◽  
...  
Keyword(s):  
Coronary Heart Disease ◽  
Heart Disease ◽  
Infection Type ◽  
Bloodstream Infections ◽  
Infection Frequency ◽  
Acute Infections ◽  
Chd Risk ◽  
Increased Risk ◽  
Infection Types ◽  
Tract Infections

Introduction: Acute infections are known triggers of coronary heart disease (CHD). It is unclear how the strength of the association varies by infection type. Hypothesis: We hypothesized that all acute infections increase CHD risk but the level of increased risk varies by infection type. Methods: Incident CHD (myocardial infarction and fatal CHD) cases were identified and adjudicated in the ARIC cohort. ARIC participants were linked to Medicare claims data. We used ICD-9 codes to identify 4 infection types based on infection frequency: cellulitis, pneumonia, urinary tract infections (UTI), and bloodstream infections. We used a case-crossover design and conditional logistic regression to compare infections among CHD cases 90 days before the event with two corresponding control periods 1 year and 2 years prior. The Wald test was used to assess differences between infection types. Results: A total of 1,312 CHD cases were identified. Among cases, 43 had cellulitis, 102 had pneumonia, 116 had a UTI, and 28 had a bloodstream infection within 90 days of the CHD event. All infection types were associated with higher CHD risk within 90 days of the infection; (odds ratios and 95% Cis) (cellulitis = 1.41 (0.93, 2.15), pneumonia = 5.60 (3.72, 8.43), UTI = 2.62 (1.92, 3.57), bloodstream infections = 4.77 (2.34, 9.71)) although cellulitis was not statistically significant (Figure). The association between infection and CHD was significantly stronger for pneumonia, UTI, and bloodstream infections compared to cellulitis (p<0.05). Pneumonia and bloodstream infections were stronger CHD triggers compared to UTI but only pneumonia reached statistical significance (p<0.05). Conclusions: Patients with pneumonia or bloodstream infections may be at particularly elevated CHD risk. Clinical trials of CHD preventive therapies during and immediately following infection to reduce the otherwise elevated CHD risk are needed. Healthcare providers should consider CHD risk during and immediately after infection and optimize preventive therapies.

THE ORIGIN OF A NEW PHYSIOLOGIC RACE OF CROWN RUST VIRULENT ON THE OAT VARIETIES VICTORIA AND SAIA

1963 ◽  
Vol 41 (12) ◽  
pp. 1613-1615 ◽  
Author(s):  
George Fleischmann
Keyword(s):  
Host Resistance ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
Racial Composition ◽  
Physiologic Race ◽  
Close Relationship ◽  
Selective Forces ◽  
Canadian Provinces ◽  
New Race

A new physiologic race of crown rust, Puccinia coronata Corda f. sp. avenae Erikss., was isolated from oats collected in four Canadian provinces in 1962. This race, 332, is one of the first reported that is capable of attacking both the differential oat varieties Victoria and Saia. A close relationship exists between race 332 and race 216, which suggests that the former may have arisen from the latter by mutation. The evolution of this new race has occurred in the absence of any known Saia type resistance in current commercial varieties, and its survival points up the operation of selective forces other than host resistance on the racial composition of the pathogenic population.

scholarly journals Comparisons of Visual Rust Assessments and DNA Levels of Phakopsora pachyrhizi in Soybean Genotypes Varying in Rust Resistance

Plant Disease ◽  
2011 ◽  
Vol 95 (8) ◽  
pp. 1007-1012 ◽  
Author(s):  
C. Paul ◽  
C. B. Hill ◽  
G. L. Hartman
Keyword(s):  
Quantitative Polymerase Chain Reaction ◽  
Single Gene ◽  
The Other ◽  
Soybean Rust ◽  
Disease Assessment ◽  
Fungal Colonization ◽  
Phakopsora Pachyrhizi ◽  
Breeding Populations ◽  
Soybean Genotypes ◽  
Infection Types

Soybean resistance to Phakopsora pachyrhizi, the cause of soybean rust, has been characterized by the following three infection types: (i) immune response (IM; complete resistance) with no visible lesions, (ii) resistant reaction with reddish brown (RB) lesions (incomplete resistance), and (iii) susceptible reaction with tan-colored (TAN) lesions. Based on visual assessments of these phenotypes, single gene resistance in soybean to P. pachyrhizi has been documented, but colonization within infected tissues based on fungal DNA (FDNA) levels in different soybean genotypes had not been analyzed. The research used a quantitative polymerase chain reaction (Q-PCR) assay to compare visual disease assessment to FDNA in controlled inoculation experiments using two isolates of P. pachyrhizi. The objective of the first experiment was to compare data from digital visual disease assessment to FDNA from Q-PCR assays using digital visual disease assessment using five resistant soybean genotypes (one IM and four RB) and five susceptible genotypes (TAN). The objective of the second experiment was to quantify FDNA using Q-PCR at different time points after inoculation to determine if levels of fungal colonization differed in five soybean genotypes with different levels of resistance (one IM, two RB, and two TAN). For experiment 1, the numbers of uredinia and uredinia per lesion on four of the five resistant soybean genotypes were lower (P < 0.05) than the other six genotypes. Significant differences (P < 0.05) in FDNA concentrations were found among soybean genotypes with TAN lesions and among soybean genotypes with RB lesions. Soybean cultivar UG5 (IM phenotype) had significantly less (P < 0.05) FDNA than all of the other genotypes. Some genotypes that produced TAN lesions had significantly lower (P < 0.05) or non-significantly different FDNA concentrations compared to those genotypes that produced RB lesions. For experiment 2, the regression of FDNA on days after inoculation was significant (P < 0.01) with positive slopes for all genotypes except for UG5, in which FDNA declined over time, indicating a reduction of fungal colonization. The results of this Q-PCR FDNA screening technique demonstrates its use to distinguish different types of resistance, and could be used to facilitate the evaluation of soybean breeding populations, where precise quantification of incomplete and/or partial resistance is needed to identify and map quantitative trait loci.

scholarly journals Host Range and Alternate Host of a Puccinia coronata Population from Smooth Brome Grass

Plant Disease ◽  
2001 ◽  
Vol 85 (5) ◽  
pp. 513-516 ◽  
Author(s):  
N. J. Delgado ◽  
C. R. Grau ◽  
M. D. Casler
Keyword(s):  
Host Range ◽  
Agricultural Research ◽  
Infection Type ◽  
Disease Incidence ◽  
Puccinia Coronata ◽  
Grass Species ◽  
Research Station ◽  
Alternate Host ◽  
Smooth Brome ◽  
Brome Grass

A rust fungus was observed on smooth brome grass (Bromus inermis Leyss.) leaves growing in the fields of the University of Wisconsin (UW) Agricultural Research Station at Arlington, WI. The population (WPc-95A) was classified as Puccinia coronata Corda. Reports of P. coronata on B. inermis are rare, so a study of the pathogen host range, alternate host, and morphology of urediniospores and teliospores was undertaken. Fourteen grass species representing 10 genera were inoculated with P. coronata WPc-95A, which was maintained with repeated inoculations on B. inermis cv. PL-BDR1. Seventy-two 30-day-old seedlings of B. inermis were inoculated with urediniospores of the fungus. Infection type, pustule density, and disease incidence were recorded 15 days after inoculation. The same grass cultivars were also inoculated with aecio-spores collected from Rhamnus cathartica L. located on the UW campus. To test for host specificity, urediniospores produced on aeciospore-susceptible grass species were used to reinoculate plants of B. inermis and the host species from which the urediniospores were derived. B. inermis, B. riparius Rehm., Festuca pratensis Huds., and Lolium perenne L. were susceptible to P. coronata WPc-95A. The two Bromus spp. had the highest disease incidence. R. cathartica was found to be an alternate host of P. coronata WPc-95A, as it is for P. coronata isolates found on F. pratensis. However, cross-inoculations with urediniospores from R. cathartica-derived aeciospore infections indicated that only urediniospores of B. inermis origin were capable of infecting B. inermis. Thus, P. coronata WPc-95A appears to belong to a forma speciales previously undescribed in North America.

Effect of post-inoculation temperature and light intensity on expression of resistance to stripe rust in some Australian wheat cultivars

1994 ◽  
Vol 45 (7) ◽  
pp. 1379 ◽  
Author(s):  
GJ Ash ◽  
RG Rees
Keyword(s):  
Stripe Rust ◽  
Puccinia Striiformis ◽  
Infection Type ◽  
High Light ◽  
Post Inoculation ◽  
Wheat Cultivars ◽  
Susceptible Host ◽  
Light Intensities ◽  
Australian Wheat ◽  
Infection Types

Temperature sensitive resistance to stripe rust in selected Australian wheat cultivars was found to be most strongly expressed at a constant post-inoculation temperature of l9�C and at high light intensities. At 25�C the infection type on the susceptible host was reduced, indicating incompatability, while at the lower temperature of 13�C all cultivars were susceptible to the rust. At low light intensities there was a movement towards low infection types in cultivars possessing this resistance even at low temperatures. This made it essential to use high light intensities to differentiate this resistance to stripe rust. The host-pathogen interaction leading to the low infection types became irreversible after 6 to 7 days' exposure to the higher temperatures. As well as affecting disease progress towards the end of the growing season in the warmer areas of the wheat belt, this resistance could have a marked effect on the ability of Puccinia striiformis fsp. tritici to oversummer in the Australian wheat growing areas.

The Chinese and Japanese in the Census

2017 ◽  
Author(s):  
Paul Schor
Keyword(s):  
Asian Immigrants ◽  
The Other ◽  
Place Of Birth ◽  
Racial Categories ◽  
The Us ◽  
European Immigrants ◽  
New Race ◽  
The One ◽  
Us Census ◽  
Foreign Birth

This chapter discusses the integration of Chinese and Japanese into the US census. The American census added a new race it termed “Chinese” to its questionnaires beginning in 1870 and “Japanese” in 1890. The remarkable thing is that what was a nationality immediately became a race as well. Since 1850, the place of birth of all inhabitants had been recorded, whether or not they were immigrants, and in the case of non-European immigrants, two categories of origin were involved: on the one hand, foreign birth, and on the other hand, race, which was transmitted to the following generations. In spite of their small numbers, Asian immigrants were the object of disproportionate attention in the US census, to the point that in 1920, out of nine possible racial categories, five were Asian.

scholarly journals 1036. Clinical impact of an antibiotic time out initiative at an academic medical center

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S364-S365
Author(s):  
Amy P Taylor ◽  
Kelci E Coe ◽  
Kurt Stevenson ◽  
Lynn Wardlow ◽  
Zeinab El Boghdadly ◽  
...  
Keyword(s):  
Infection Type ◽  
Medical Center ◽  
Academic Medical Center ◽  
Kidney Injury ◽  
Primary Objective ◽  
Clinical Impact ◽  
Exact Test ◽  
Time Out ◽  
The Ohio State University ◽  
Infection Types

Abstract Background The Infectious Diseases Society of America’s guideline for implementing antibiotic (abx) stewardship recommends routine review of abx use. Several studies demonstrate antibiotic time out (ATO) programs result in de-escalation, but there is limited evidence of improved outcomes. The aim of this study was to evaluate the clinical impact of ATO. Methods This retrospective study included hospitalized patients at The Ohio State University Wexner Medical Center receiving abx and a documented ATO from 7/1/2017 to 6/30/2018. ATO patients were matched by infection type to abx-treated patients lacking an ATO note. Patients were excluded if they were identified as a protected population, were in the ICU at the time of ATO, had an ATO within 48 hours of discharge, cystic fibrosis, or febrile neutropenia. The primary objective was to evaluate abx optimization in patients with documented ATO vs. those without ATO. Abx optimization was defined as the selection of ideal abx based on guidelines, culture and susceptibility results, or expert opinion when undefined. Secondary outcomes included vancomycin-associated acute kidney injury (VAN-AKI), infection-related length of stay (LOS), all-cause 30-day readmission or mortality, abx days, and nosocomial C. difficile infection (CDI) rates. The Student t-test/Fisher’s exact test and Wilcoxon-rank sum were utilized as appropriate. Results One hundred ATO patients were compared with 100 non-ATO patients. Baseline characteristics and infection types were similar between groups. ATO resulted in improved optimization of abx selection (P = 0.05) and duration (P < 0.01), and reduced piperacillin/tazobactam (P/T) and vancomycin (VAN) utilization. No difference was observed in VAN-AKI (22 vs. 20%, P = 0.73), 30-day readmission (28 vs. 27%, P = 0.87), mortality (5 vs. 5%, P = 1), or CDI rates (6 vs. 5%, p = 0.76) in the ATO vs. non-ATO group. However, inpatient abx days (12 vs. 8, P = 0.004) and infection-related LOS (10 vs. 8, P = 0.0006) were shorter in the non-ATO group. Conclusion ATO improved optimization of abx selection and duration, and reduced P/T and VAN use. Despite this, clinical outcomes were not improved. Disclosures All authors: No reported disclosures.

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