scholarly journals Variation in Susceptibility of Tanoak to the NA1 and EU1 Lineages of Phytophthora ramorum, the Cause of Sudden Oak Death

Plant Disease ◽  
2019 ◽  
Vol 103 (12) ◽  
pp. 3154-3160 ◽  
Author(s):  
Kelsey L. Søndreli ◽  
Alan Kanaskie ◽  
Susanna Keriö ◽  
Jared M. LeBoldus
Keyword(s):  
Disease Resistance ◽  
Forest Ecosystems ◽  
Phytophthora Ramorum ◽  
Sudden Oak Death ◽  
Artificial Inoculation ◽  
Lesion Length ◽  
Significant Difference ◽  
Notholithocarpus Densiflorus ◽  
The Impact ◽  
Inoculation Assay

Phytophthora ramorum, the cause of sudden oak death (SOD), kills tanoak (Notholithocarpus densiflorus) trees in southwestern Oregon and California. Two lineages of P. ramorum are now found in wildland forests of Oregon (NA1 and EU1). In addition to the management of SOD in forest ecosystems, disease resistance could be used as a way to mitigate the impact of P. ramorum. The objectives of this study were to (i) characterize the variability in resistance of N. densiflorus among families using lesion length; (ii) determine whether lineage, isolate, family, or their interactions significantly affect variation in lesion length; and (iii) determine whether there are differences among isolates and among families in terms of lesion length. The parameters isolate nested within lineage (isolate[lineage]) and family × isolate(lineage) interaction explained the majority of the variation in lesion length. There was no significant difference between the NA1 and EU1 lineages in terms of mean lesion length; however, there were differences among the six isolates. Lesions on seedlings collected from surviving trees at infested sites were smaller, on average, than lesions of seedlings collected from trees at noninfested sites (P = 0.0064). The results indicate that there is potential to establish a breeding program for tanoak resistance to SOD and that several isolates of P. ramorum should be used in an artificial inoculation assay.

Forest transformation resulting from an exotic pathogen: regeneration and tanoak mortality in coast redwood stands affected by sudden oak death

2011 ◽  
Vol 41 (4) ◽  
pp. 763-772 ◽  
Author(s):  
Benjamin S. Ramage ◽  
Kevin L. O’Hara ◽  
Alison B. Forrestel
Keyword(s):  
Canopy Cover ◽  
Phytophthora Ramorum ◽  
Sudden Oak Death ◽  
Coast Redwood ◽  
Marin County ◽  
Wildlife Species ◽  
Management Interventions ◽  
Redwood Forests ◽  
Exotic Pathogen ◽  
Notholithocarpus Densiflorus

Sudden oak death is dramatically altering forests throughout coastal California, but little is known about the communities that are assembling in affected areas. This emerging disease, caused by the exotic pathogen Phytophthora ramorum (S. Werres, A.W.A.M. de Cock), has had especially severe effects on tanoak ( Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh), a broadleaf evergreen that is abundant in forests dominated by coast redwood ( Sequoia sempervirens (D.Don) Endl.). Tanoak, a valuable food source to numerous wildlife species, is unlikely to successfully regenerate in diseased areas, and thus, affected redwood forests are transitioning to a novel state. In this study, to predict which species might replace tanoak, we investigated regeneration patterns in heavily impacted stands in Marin County, California. Our main findings were as follows: (i) despite reductions in canopy cover, there is no evidence that any species other than tanoak has exhibited a regenerative response to tanoak mortality, (ii) the regeneration stratum was dominated by redwood and tanoak (other tree species were patchy and (or) scarce), and (iii) some severely affected areas lacked sufficient regeneration to fully re-occupy available growing space. Our results indicate that redwood is likely to initially re-occupy the majority of the ground relinquished by tanoak, but also provide evidence that longer-term trajectories are unresolved, and may be highly responsive to management interventions.

Novel introductions and epidemic dynamics of the sudden oak death pathogen Phytophthora ramorum in Oregon forests

2020 ◽  
Author(s):  
Nicholas C Carleson ◽  
Hazel Daniels ◽  
Paul Reeser ◽  
Alan Kanaskie ◽  
Sarah Navarro ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Population Dynamics ◽  
Microsatellite Loci ◽  
Forest Ecosystems ◽  
Principal Component ◽  
Phytophthora Ramorum ◽  
Sudden Oak Death ◽  
Clonal Lineage ◽  
Epidemic Dynamics ◽  
One Year

Sudden oak death caused by Phytophthora ramorum has been actively managed in Oregon since the early 2000’s. To date, this epidemic has been driven mostly by the NA1 clonal lineage of P. ramorum, but an outbreak of the EU1 lineage has recently emerged. Here we contrast the population dynamics of the NA1 outbreak first reported in 2001 to the outbreak of the EU1 lineage first detected in 2015. We tested if any of the lineages were introduced more than once. Infested regions of the forest were sampled between 2013-2018 (n = 903) and strains were genotyped at 15 microsatellite loci. Most genotypes observed were transient, with 272 of 358 unique genotypes emerging one year and disappearing the next. Diversity of EU1 was very low and isolates were spatially clustered (< 8 km apart), suggesting a single EU1 introduction. Some forest isolates are genetically similar to isolates collected from a local nursery in 2012, suggesting introduction of EU1 from this nursery or simultaneous introduction to both the nursery and latently into the forest. In contrast, the older NA1 populations were more polymorphic and spread over 30 km2. Principal component analysis supported two to four independent NA1 introductions. The NA1 and EU1 epidemics infest the same area but show disparate demographics owing to initial introductions of the lineages spaced 10 years apart. Comparing these epidemics provides novel insights into patterns of emergence of clonal pathogens in forest ecosystems.

scholarly journals Screening Cotoneaster for Resistance to Fire Blight by Artificial Inoculation

HortScience ◽  
2014 ◽  
Vol 49 (12) ◽  
pp. 1480-1485 ◽  
Author(s):  
Joseph J. Rothleutner ◽  
Ryan N. Contreras ◽  
Virginia O. Stockwell ◽  
James S. Owen
Keyword(s):  
Disease Resistance ◽  
Fire Blight ◽  
Bacterial Pathogen ◽  
Artificial Inoculation ◽  
Lesion Length ◽  
Sources Of Resistance ◽  
Landscape Plants ◽  
Whole Plant ◽  
Wide Range ◽  
Disease Pressure

Cotoneaster Medik. is a genus of ornamental landscape plants commonly affected by fire blight. Fire blight is a disease caused by the bacterial pathogen, Erwinia amylovora (Burrill) Winslow et al., that attacks a wide range of taxa in the apple subfamily (Maloideae; Rosaceae). To assess susceptibility of species and identify potential sources of resistance, we inoculated 52 taxa of Cotoneaster with E. amylovora. Disease severity was scored by percent shoot necrosis (lesion length/total shoot length). Disease screenings were conducted over 2 years and varying levels of susceptibility were observed. Some taxa were highly susceptible to fire blight and the disease resulted in whole plant mortality (C. rhytidophyllus Rehder & E.H. Wilson, C. rugosus E. Pritzel ex Diels, and C. wardii W.W. Smith). Other taxa repeatedly exhibited moderate to high levels of disease resistance [C. arbusculus G. Klotz, C. chungtinensis (T.T. Yu) J. Fryer & B. Hylmö, C. delsianus E. Pritzel var. delsianus, C. sikangensis Flinck & B. Hylmö, C. simonsii Baker, and C. splendens Flinck & Hylmö]. Ongoing studies are being conducted to determine if taxa with high levels of resistance under artificial inoculation will exhibit high levels of resistance in the field under natural disease pressure. Identifying sources of disease resistance will be useful for breeding programs to increase tolerance of these landscape plants with desirable horticultural characteristics to fire blight.

scholarly journals Phytophthora ramorum Does Not Cause Physiologically Significant Systemic Injury to California Bay Laurel, Its Primary Reservoir Host

2009 ◽  
Vol 99 (11) ◽  
pp. 1307-1311 ◽  
Author(s):  
M. V. DiLeo ◽  
R. M. Bostock ◽  
D. M. Rizzo
Keyword(s):  
Photosynthetic Efficiency ◽  
Reservoir Host ◽  
Phytophthora Ramorum ◽  
Sudden Oak Death ◽  
Ecological Fitness ◽  
Umbellularia Californica ◽  
Physiological Impact ◽  
The Impact ◽  
Significant Injury

California bay laurel trees (Umbellularia californica) play a crucial role in the reproduction and survival of Phytophthora ramorum in coastal California forests by supporting sporulation during the rainy season and by providing a means for the pathogen to survive the dry, Mediterranean summer. While bay laurel is thus critical to the epidemiology of sudden oak death and other P. ramorum diseases in California, the relatively minor symptoms observed on this reservoir host suggest that it may not sustain ecologically significant injury itself. The long-term role that P. ramorum will play in California forests will depend in part on the extent to which this pathogen decreases the ecological fitness of bay laurel. Despite the importance of this question, no study has yet investigated in detail the physiological impact that ramorum blight imposes on bay laurel. This experimental study quantifies the impact that P. ramorum has on artificially inoculated bay laurel seedlings with measurements that integrate the full injury that infection with an oomycete may cause: photosynthetic efficiency, total photosynthetic area, and growth. Leaf area and leaf mass were not impacted significantly by infection of P. ramorum. Photosynthetic efficiency was mildly depressed in symptomatic, but not asymptomatic leaves, despite unnaturally high levels of necrosis that were imposed on the seedlings. These results demonstrate that bay laurel trees suffer only minor injury from ramorum blight beyond visible necrotic symptoms. Consequently, it is highly likely that bay laurel will continue to be widely available as a host for P. ramorum in California forests, which has long-term implications for the composition of these forests.

Measuring Impact of Stress in Sandwich Generation Caring for Demented Parents

GeroPsych ◽  
2014 ◽  
Vol 27 (4) ◽  
pp. 171-179 ◽  
Author(s):  
Laurence M. Solberg ◽  
Lauren B. Solberg ◽  
Emily N. Peterson
Keyword(s):  
Factor Analysis ◽  
Exploratory Factor Analysis ◽  
Social Worker ◽  
Resource Availability ◽  
Well Being ◽  
Sandwich Generation ◽  
Item Questionnaire ◽  
Significant Difference ◽  
Adult Caregivers ◽  
The Impact

Stress in caregivers may affect the healthcare recipients receive. We examined the impact of stress experienced by 45 adult caregivers of their elderly demented parents. The participants completed a 32-item questionnaire about the impact of experienced stress. The questionnaire also asked about interventions that might help to reduce the impact of stress. After exploratory factor analysis, we reduced the 32-item questionnaire to 13 items. Results indicated that caregivers experienced stress, anxiety, and sadness. Also, emotional, but not financial or professional, well-being was significantly impacted. There was no significant difference between the impact of caregiver stress on members from the sandwich generation and those from the nonsandwich generation. Meeting with a social worker for resource availability was identified most frequently as a potentially helpful intervention for coping with the impact of stress.

Implicit and explicit corrective feedback and feedback exposure conditions

2020 ◽  
Vol 4 (1) ◽  
pp. 3-48
Author(s):  
Takehiro Iizuka ◽  
Kimi Nakatsukasa
Keyword(s):  
Explicit Knowledge ◽  
Corrective Feedback ◽  
Significant Difference ◽  
Oral Corrective Feedback ◽  
Post Test ◽  
Picture Description ◽  
Potential Factors ◽  
Implicit And Explicit ◽  
Instructional Settings ◽  
The Impact

This exploratory study examined the impact of implicit and explicit oral corrective feedback (CF) on the development of implicit and explicit knowledge of Japanese locative particles (activity de, movement ni and location ni) for those who directly received CF and those who observed CF in the classroom. Thirty-six college students in a beginning Japanese language course received either recast (implicit), metalinguistic (explicit) or no feedback during an information-gap picture description activity, and completed a timed picture description test (implicit knowledge) and an untimed grammaticality judgement test (explicit knowledge) in a pre-test, immediate post-test and delayed post-test. The results showed that overall there was no significant difference between CF types, and that CF benefited direct and indirect recipients similarly. Potential factors that might influence the effectiveness of CF, such as instructional settings, complexity of target structures and pedagogy styles, are discussed.

Reducing the Social Stigma Associated with Obsessive Compulsive Disorder: A Controlled Trial of an Intervention Program in a Turkish Community Sample

2020 ◽  
Vol 20 (2) ◽  
pp. 101-120
Author(s):  
Ayça Aktaç Gürbüz ◽  
Orçun YORULMAZ ◽  
Gülşah DURNA
Keyword(s):  
Obsessive Compulsive Disorder ◽  
Intervention Program ◽  
Controlled Trial ◽  
Community Sample ◽  
Case Vignette ◽  
Control Group ◽  
Obsessive Compulsive ◽  
Compulsive Disorder ◽  
Significant Difference ◽  
The Impact

Scientific research into the reduction of stigmatization, particularly related to specific problems such as Obsessive-Compulsive Disorder (OCD), is scarce. In the present study, we examine the impact of a video-based antistigma intervention program for OCD in a pretest-posttest control group research. After being randomly assigned to either an intervention (n= 101) or control group (n= 96), the participants reported their attitudes on a hypothetical case vignette before and after OCD vs. Multiple Sclerosis (MS) videos, and again six months later as a follow up assessment. The mixed design analyses for the group comparisons indicated that although there was no significant difference in the measures of the control group, the participants watching the anti-stigma OCD video, in which the focus was psychoeducation and interaction strategies, reported significantly lower scores on social distances and negative beliefs for the case vignettes they read, and this difference was maintained six months later. Then, the present results indicate the effectiveness of our anti-stigma intervention program for OCD. Interventions to reduce stigmatization can also be viewed as effective tools for changing the attitudes of people toward OCD, although further research and applications are needed related to specific disorders if a longlasting impact is to be achieved.

Antecedents And Outcomes Of Qwl Among Employees In Banks

2019 ◽  
Vol 118 (7) ◽  
pp. 1-19
Author(s):  
Geethanjali N ◽  
Parveen Roja M ◽  
Lavanya D
Keyword(s):  
Organizational Climate ◽  
Job Stress ◽  
Work Life ◽  
Working Environment ◽  
Quality Of Work Life ◽  
Quality Of Work ◽  
Significant Difference ◽  
Service Productivity ◽  
The Impact

Quality of work life is the major factor to be considered in working environment of any organization. The performance of employees and the organization lies on the ability of the employees based on working environment. The QWL leads to better working environment which improves the performance of organization. The present study has made an attempt to find the level of factors causing QWL and the impact of outcome of QWL in banks. Since the profile of the banks may be associated with the level of outcomes of QWL, the present study has made an attempt to examine it with the help of one way analysis of variance and t-test. The included outcomes of QWL are job satisfaction, job stress, organizational climate, organizational commitment, employees retention behaviour, service quality employees and service productivity of employees. The highly associated determinants of QWL and the significant difference among the PUSBs and PRSBs have been noticed. The significantly associating important profiles of the banks regarding the existence of outcome of QWL are identified.

Оrganic Meat Production of Broiler Chickens Hubbard Redbro Cross

2020 ◽  
Keyword(s):  
Broiler Chickens ◽  
Raw Materials ◽  
Animal Health ◽  
Meat Products ◽  
Poultry Meat ◽  
Meat Production ◽  
Significant Difference ◽  
Environmentally Safe ◽  
The Impact

This article presents the results of studying the impact of housing and feeding conditions on broiler chickens of Hubbard RedBro cross, as well as the quality of products obtained when using floor and cage content, in a farm. It established that when receiving a mixed feed of own production using feed raw materials grown on a farm without the use of pesticides, a statistically significant decrease in potentially dangerous substances for animal health is recorded. Compared with factory feed, it has reduced the content of pesticides by 14 times, and mercury and arsenic by 24 times, cadmium by five times, and lead by ten times. The results of the study of economic indicators of growing Hubbard RedBro cross broiler chickens, as well as the chemical composition and quality of carcasses, indicated that there was no significant difference between the floor and cell conditions of keeping. Still, the use of a diet based on eco-feeds contributed to a statistically significant decrease in the concentration of toxic metals in the muscles of the poultry of the experimental groups. As a result, it found that the use of the studied compound feed in the diets of broiler chickens increased the indicators of Biosafety and ensured the production of environmentally safe ("organic") poultry meat products.

Characteristics of monitored diabetic patients by glycated haemoglobin (HbA1c)

2016 ◽  
Vol 5 (05) ◽  
pp. 4563
Author(s):  
Tariq A. Zafar
Keyword(s):  
Blood Glucose ◽  
Glycemic Control ◽  
Glycated Haemoglobin ◽  
Poor Glycemic Control ◽  
Diabetic Patients ◽  
Age Group ◽  
Hba1c Test ◽  
Significant Difference ◽  
Tract Infections ◽  
The Impact

Glycated haemoglobin (HbA1c) test indicates the blood glucose levels for the previous two to three months. Using HbA1c test may overcome many of the practical issues and prevent infections such as urinary tract infections (UTIs). The study aimed to evaluate the impact of glycemic control using HbA1c test to understand patient characteristics and UTIs prevalence. Glycemic control was evaluated by measuring HbA1c for a total of 208 diabetes patients who were regularly attending diabetes center in Al-Noor specialist hospital in Makkah.  The results showed that good and moderate glycemic controlled patients were 14.9% and 16.9% respectively while the poor glycemic patients were 68.3%. Among the good improved glycemic control, 83.9% were females, 48.4% were from age group (15-44y). Among the moderately improved glycemic control, 68.4% were females, 54.3% were from age group (45-64 y) with no significant difference. The total number of the patients with positive UTIs was 55 (26.4%) while the total number of patients with negative was UTIs 153 (73.6%). Among the positive UTIs, 76.3% were with poor glycemic control while only 12.3% and 11% were moderate and good improved glycemic control respectively. Among the negative UTIs, 65.3% were with poor glycemic control while only 19% and 15.7% were with moderate and good improved glycemic control respectively.  Prevalence of UTIs among diabetic patients was not significant (p > 0.05). It was concluded that HbA1c was useful monitoring tool for diabetes mellitus and may lead to improved outcomes. Using a HbA1c test may overcome many of the practical issues that affect the blood glucose tests.

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