scholarly journals Mapping crown rust resistance at multiple time points in elite oat germplasm

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Ian G. McNish ◽  
Cristiano M. Zimmer ◽  
Alexander Q. Susko ◽  
D. Jo Heuschele ◽  
Tyler Tiede ◽  
...  
Keyword(s):  
Rust Resistance ◽  
Crown Rust ◽  
Multiple Time ◽  
Time Points ◽  
Crown Rust Resistance ◽  
Multiple Time Points

scholarly journals Use of TanDEM-X and SRTM-C Data for Detection of Deforestation Caused by Bark Beetle in Central European Mountains

2021 ◽  
Vol 13 (15) ◽  
pp. 3042
Author(s):  
Kateřina Gdulová ◽  
Jana Marešová ◽  
Vojtěch Barták ◽  
Marta Szostak ◽  
Jaroslav Červenka ◽  
...  
Keyword(s):  
Bark Beetle ◽  
Synergistic Effects ◽  
Canopy Height ◽  
Surface Model ◽  
Multiple Time ◽  
Central European ◽  
Time Points ◽  
Bohemian Forest ◽  
Multiple Time Points ◽  
Surrounding Areas

The availability of global digital elevation models (DEMs) from multiple time points allows their combination for analysing vegetation changes. The combination of models (e.g., SRTM and TanDEM-X) can contain errors, which can, due to their synergistic effects, yield incorrect results. We used a high-resolution LiDAR-derived digital surface model (DSM) to evaluate the accuracy of canopy height estimates of the aforementioned global DEMs. In addition, we subtracted SRTM and TanDEM-X data at 90 and 30 m resolutions, respectively, to detect deforestation caused by bark beetle disturbance and evaluated the associations of their difference with terrain characteristics. The study areas covered three Central European mountain ranges and their surrounding areas: Bohemian Forest, Erzgebirge, and Giant Mountains. We found that vertical bias of SRTM and TanDEM-X, relative to the canopy height, is similar with negative values of up to −2.5 m and LE90s below 7.8 m in non-forest areas. In forests, the vertical bias of SRTM and TanDEM-X ranged from −0.5 to 4.1 m and LE90s from 7.2 to 11.0 m, respectively. The height differences between SRTM and TanDEM-X show moderate dependence on the slope and its orientation. LE90s for TDX-SRTM differences tended to be smaller for east-facing than for west-facing slopes, and varied, with aspect, by up to 1.5 m in non-forest areas and 3 m in forests, respectively. Finally, subtracting SRTM and NASA DEMs from TanDEM-X and Copernicus DEMs, respectively, successfully identified large areas of deforestation caused by hurricane Kyril in 2007 and a subsequent bark beetle disturbance in the Bohemian Forest. However, local errors in TanDEM-X, associated mainly with forest-covered west-facing slopes, resulted in erroneous identification of deforestation. Therefore, caution is needed when combining SRTM and TanDEM-X data in multitemporal studies in a mountain environment. Still, we can conclude that SRTM and TanDEM-X data represent suitable near global sources for the identification of deforestation in the period between the time points of their acquisition.

Meta-analysis of effect sizes reported at multiple time points: A multivariate approach

2012 ◽  
Vol 9 (5) ◽  
pp. 610-620 ◽  
Author(s):  
Thomas A Trikalinos ◽  
Ingram Olkin
Keyword(s):  
Random Effects ◽  
Treatment Effects ◽  
Multivariate Analyses ◽  
Meta Analysis ◽  
Effect Sizes ◽  
Multiple Time ◽  
Time Points ◽  
Fixed And Random Effects ◽  
Multiple Time Points ◽  
Meta Analyses

Background Many comparative studies report results at multiple time points. Such data are correlated because they pertain to the same patients, but are typically meta-analyzed as separate quantitative syntheses at each time point, ignoring the correlations between time points. Purpose To develop a meta-analytic approach that estimates treatment effects at successive time points and takes account of the stochastic dependencies of those effects. Methods We present both fixed and random effects methods for multivariate meta-analysis of effect sizes reported at multiple time points. We provide formulas for calculating the covariance (and correlations) of the effect sizes at successive time points for four common metrics (log odds ratio, log risk ratio, risk difference, and arcsine difference) based on data reported in the primary studies. We work through an example of a meta-analysis of 17 randomized trials of radiotherapy and chemotherapy versus radiotherapy alone for the postoperative treatment of patients with malignant gliomas, where in each trial survival is assessed at 6, 12, 18, and 24 months post randomization. We also provide software code for the main analyses described in the article. Results We discuss the estimation of fixed and random effects models and explore five options for the structure of the covariance matrix of the random effects. In the example, we compare separate (univariate) meta-analyses at each of the four time points with joint analyses across all four time points using the proposed methods. Although results of univariate and multivariate analyses are generally similar in the example, there are small differences in the magnitude of the effect sizes and the corresponding standard errors. We also discuss conditional multivariate analyses where one compares treatment effects at later time points given observed data at earlier time points. Limitations Simulation and empirical studies are needed to clarify the gains of multivariate analyses compared with separate meta-analyses under a variety of conditions. Conclusions Data reported at multiple time points are multivariate in nature and are efficiently analyzed using multivariate methods. The latter are an attractive alternative or complement to performing separate meta-analyses.

INHERITANCE OF CROWN RUST RESISTANCE IN THREE ACCESSIONS OF AVENA STERILIS

1980 ◽  
Vol 22 (1) ◽  
pp. 27-33 ◽  
Author(s):  
D. E. Harder ◽  
R. I. H. McKenzie ◽  
J. W. Martens
Keyword(s):  
Rust Resistance ◽  
Dominant Gene ◽  
Crown Rust ◽  
Inheritance Of Resistance ◽  
Single Dominant Gene ◽  
Avena Sterilis ◽  
Oat Crown Rust ◽  
Crown Rust Resistance ◽  
Resistance Spectrum ◽  
Dominant Genes

The inheritance of resistance to oat crown rust was studied in three accessions of Avena sterilis L. Accession CAV 4274 originated from Morocco, CAV 4540 from Algeria, and CAV 3695 from Tunisia. Seedling rust tests on F2 backcross families indicated the presence of two dominant genes for crown rust resistance in CAV 4274. One of these, a gene conditioning resistance to most races tested, was linked or allelic to gene Pc-38, and was designated gene Pc-62. The second gene conferred resistance only to one of the six races studied, and was not tested further. In CAV 4540, a single dominant gene, Pc-63 was possibly allelic with Pc-62 and linked or allelic to Pc-38. Genes Pc-62 and 63 are generally similar to Pc-38 in their resistance spectrum, but these three genes are differentiated by races CR 102, CR 103, and CR 107. A single dominant gene in CAV 3695 appeared to be Pc-50.

THE ROLE OF MEMORY PERSPECTIVE IN SOCIAL PHOBIA: IMMEDIATE AND DELAYED MEMORIES FOR ROLE-PLAYED SITUATIONS

2002 ◽  
Vol 30 (4) ◽  
pp. 415-425 ◽  
Author(s):  
Meredith E. Coles ◽  
Cynthia L. Turk ◽  
Richard G. Heimberg
Keyword(s):  
Social Phobia ◽  
Multiple Time ◽  
Behavioral Models ◽  
Social Situations ◽  
Time Points ◽  
Cognitive Behavioral Models ◽  
Multiple Time Points ◽  
Memory Perspective ◽  
Field Perspective

Cognitive-behavioral models (Clark & Wells, 1995; Rapee & Heimberg, 1997) and recent research suggest that individuals with social phobia (SP) experience both images (Hackmann, Surawy, & Clark, 1998) and memories (Coles, Turk, Heimberg, & Fresco, 2001; Wells, Clark, & Ahmad, 1998) of anxiety-producing social situations from an observer perspective. The current study examines memory perspective for two role-played situations (speech and social interaction) at multiple time points (immediate and 3 weeks post) in 22 individuals with generalized SP and 30 non-anxious controls (NACs). At both time points, SPs recalled the role-plays from a more observer/less field perspective than did NACs. Further, over time, the memory perspective of SPs became even more observer/less field while the memory perspective of NAC remained relatively stable.

The Silicon Peaches

2021 ◽  
pp. 31-42
Author(s):  
Dan Breznitz
Keyword(s):  
Information And Communication Technologies ◽  
Silicon Valley ◽  
Communication Technologies ◽  
Multiple Time ◽  
Rapid Rise ◽  
Time Points ◽  
Start Up ◽  
Information And Communication ◽  
Multiple Time Points ◽  
Start Ups

This chapter acknowledges that, for many regions, the idea of attracting cutting-edge tech start-ups is almost irresistible. Seemingly every community aspires to become the next Silicon Valley. But is that feasible? This chapter make these lessons concrete by elaborating on the rapid rise and, even faster and deeper, decline of America’s first Silicon Valley—Cleveland, Ohio. It then shows the near impossibility of trying to become the next Silicon Valley by analyzing the mysterious failure of Atlanta, Georgia—a city that diligently followed all the advice ever given to an aspiring new start-up hub, but somehow was always left only with the “potential.” We will see how at multiple time-points Atlanta’s companies were the leading innovators with the best products in the newest information and communication technologies (ICT), only to falter and be taken over by Silicon Valley companies without leaving any apparent impact on the region. It then brings in social-network research and the concept of embeddedness to explain why trying to recreate a Silicon Valley is a doomed (and expensive) enterprise.

Leggett Oat

2007 ◽  
Vol 87 (3) ◽  
pp. 509-512 ◽  
Author(s):  
J. W. Mitchell Fetch ◽  
S. D. Duguid ◽  
P. D. Brown ◽  
J. Chong ◽  
T. G. Fetch ◽  
...  
Keyword(s):  
Avena Sativa ◽  
Rust Resistance ◽  
Barley Yellow Dwarf Virus ◽  
Kernel Weight ◽  
Crown Rust ◽  
Good Resistance ◽  
Beta Glucan ◽  
Milling Quality ◽  
Crown Rust Resistance ◽  
Yellow Dwarf Virus

Leggett is the first oat (Avena sativa L.) cultivar released in western Canada carrying the crown rust resistance gene Pc94. Leggett carries the crown rust resistance combination Pc68 and Pc94, which provides good resistance to the crown rust populations currently present on the eastern Canadian Prairies. As a result of the presence of Pc94 providing resistance to oat crown rust, this line should exhibit excellent yield stability in the rust-prone regions of the prairies. Leggett has very good resistance to loose and covered smut, resistance to the prevalent races of oat stem rust other than NA67, but poor tolerance to barley yellow dwarf virus (BYDV). Leggett has kernel characteristics suited to milling end uses, with high test weight and 1000-kernel weight and high percent plump kernels. The beta-glucan content of Leggett is equal to or higher than that of the checks, making it a desirable milling quality cultivar. Key words: Oat, Avena sativa L., cultivar description, crown rust resistance, milling oat, Pc94

Evaluating landrace oats (Avena sp.) collected in Tunisia for crown rust resistance under natural infection

Euphytica ◽  
2007 ◽  
Vol 157 (1-2) ◽  
pp. 27-34 ◽  
Author(s):  
I. Hammami ◽  
M. B. Allagui ◽  
M. Chakroun ◽  
M. El Gazzeh
Keyword(s):  
Rust Resistance ◽  
Natural Infection ◽  
Crown Rust ◽  
Crown Rust Resistance

The inheritance of resistance to Puccinia coronata and of floret characters in Avena sterilis

1983 ◽  
Vol 25 (4) ◽  
pp. 329-335 ◽  
Author(s):  
L. S. L. Wong ◽  
R. I. H. McKenzie ◽  
D. E. Harder ◽  
J. W. Martens
Keyword(s):  
Rust Resistance ◽  
Dominant Gene ◽  
Crown Rust ◽  
Puccinia Coronata ◽  
Inheritance Of Resistance ◽  
Avena Sterilis ◽  
Field Isolates ◽  
Crown Rust Resistance ◽  
Dominant Genes

The inheritance of resistance to Puccinia coronata, awn development, lemma pubescence, and lemma color were studied in the Avena sterilis accessions CAV 4248, CAV 4656, and CAV 4904. Three independent, partially dominant genes (Pc-64, Pc-65, Pc-66) in CAV 4248, one partially dominant gene (Pc-67) in CAV 4656, and a dominant gene (Pc-68) in CAV 4904 were identified which conferred resistance to P. coronata. Genes Pc-64, Pc-65, Pc-66, Pc-67, and Pc-68 conferred resistance to 13, 8, 6, 12, and 14 races, respectively, of the 14 races of P. coronata tested. Gene Pc-68 conferred resistance to all field isolates of P. coronata collected in Canada in 1981 and was found to be closely linked or allelic to gene Pc-46. Awns and lemma pubescence were inherited monogenically in crosses with all three CAV accessions. Grey lemma color was controlled by one gene in CAV 4248 and by two genes in CAV 4656. Brown lemma color was controlled by one gene, which was closely linked or pleiotropic with the gene for lemma pubescence in CAV 4904. There was no association between crown rust resistance and the three floret characters studied.

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