CHAPTER 1: The Theory of Inoculum: The Relationship Between Disease Incidence and Inoculum Density and Dynamics of Soilborne Plant Pathogens

2017 ◽  
pp. 3-13
Author(s):  
Michael J. Jeger ◽  
Aad J. Termorshuizen
Keyword(s):  
Plant Pathogens ◽  
Disease Incidence ◽  
Inoculum Density ◽  
Soilborne Plant Pathogens ◽  
The Relationship

scholarly journals Inoculum Density-Disease Development Relationship in Verticillium Wilt of Artichoke Caused by Verticillium dahliae

Plant Disease ◽  
2007 ◽  
Vol 91 (9) ◽  
pp. 1131-1136 ◽  
Author(s):  
M. Berbegal ◽  
A. Ortega ◽  
J. García-Jiménez ◽  
J. Armengol
Keyword(s):  
Population Dynamics ◽  
Verticillium Dahliae ◽  
Symptom Severity ◽  
Disease Incidence ◽  
Growing Season ◽  
Inoculum Density ◽  
Disease Development ◽  
Growing Seasons ◽  
Negative Exponential ◽  
The Relationship

The relationship between inoculum density of Verticillium dahliae in soil and disease development was studied in 10 commercial artichoke fields. Inoculum density of V. dahliae varied between 2.2 and 34.2 microsclerotia (ms) g–1 of soil near planting. Artichoke plants were monitored for disease at the beginning and the end of each growing season. There was a significant correlation, which was best described by negative exponential models, between inoculum density and disease incidence, symptom severity, and recovery of the pathogen from the plants. Inoculum densities ranging from 5 to 9 ms g–1 of soil were associated with a mean percentage of infected plants of about 50%. Additionally, three fields were monitored in two consecutive growing seasons to evaluate the population dynamics of V. dahliae microsclerotia in soil and disease development. Numbers of microsclerotia per gram of soil decreased significantly by the end of the first growing season but slightly increased at the end of the second growing season. In these fields, symptom severity was greatest during the second growing season when high percentages of infected plants also were recorded.

Historical Foundations, Strategic Visions, and World Order

2018 ◽  
Author(s):  
Paul J. Bolt ◽  
Sharyl N. Cross
Keyword(s):  
World Order ◽  
International Order ◽  
Power Relationships ◽  
State Behavior ◽  
Political Situation ◽  
Security Issues ◽  
The World ◽  
History Of ◽  
The Relationship

Chapter 1 explores perspectives on world order, including power relationships and the rules that shape state behavior and perceptions of legitimacy. After outlining a brief history of the relationship between Russia and China that ranged from cooperation to military clashes, the chapter details Chinese and Russian perspectives on the contemporary international order as shaped by their histories and current political situation. Chinese and Russian views largely coincide on security issues, the desirability of a more multipolar order, and institutions that would enhance their standing in the world. While the Chinese–Russian partnership has accelerated considerably, particularly since the crisis in Ukraine in 2014, there are still some areas of competition that limit the extent of the relationship.

Cylindrocladium root rot in Ontario bare-root nurseries: estimate of spruce seedling losses

1988 ◽  
Vol 18 (11) ◽  
pp. 1493-1496 ◽  
Author(s):  
J. Juzwik ◽  
C. Honhart ◽  
N. Chong
Keyword(s):  
Visual Field ◽  
Root Rot ◽  
Disease Incidence ◽  
White Spruce ◽  
Visual Assessment ◽  
Inoculum Density ◽  
Field Assessment ◽  
Causal Fungus ◽  
Bare Root ◽  
Apparently Healthy

Estimates of cylindrocladium root rot losses in three black and three white spruce compartments at five Ontario bare-root nurseries were determined through visual field assessment and seedling isolation. The causal fungus, Cylindrocladiumfloridanum Sob. & C.P. Seym., was isolated from 10–77% of the symptomatic and 0–28% of the apparently healthy seedlings in each compartment. In five compartments, estimates of mean incidence based on seedling isolations and visual assessment, were higher than those based on visual assessment alone. The percentage of living spruce (apparently healthy or symptomatic) estimated to be infected in each compartment was 0.1–32.7%. No fungus isolations were attempted from dead seedlings. Mortality in the plots in the six compartments was 0.02–17.7%. The correlation between the level of Cylindrocladium incidence and the inoculum density was significant (p < 0.01) in two compartments. The use of inoculum density to predict disease incidence warrants further investigation.

scholarly journals Using Higher-Order Constructs to Estimate Health-Disease Status: The Effect of Health System Performance and Sustainability

Mathematics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1228
Author(s):  
Alicia Ramírez-Orellana ◽  
María del Carmen Valls Martínez ◽  
Mayra Soledad Grasso
Keyword(s):  
Health System ◽  
Social Services ◽  
System Performance ◽  
Structural Equation ◽  
Disease Incidence ◽  
Disease Status ◽  
Well Being ◽  
Equation Modeling ◽  
Health System Performance ◽  
The Relationship

This article aims to provide information to public agencies and policymakers on the determinants of health systems and their relationships that influence citizens’ health–disease status. A total of 61 indicators for each of 17 Spanish autonomous communities were collected from the Spanish Ministry of Health, Social Services, and Equality between 2008 and 2017. The applied technique was partial least squares structural equation modeling (PLS-SEM). Concerning health–disease status, an influence of sustainability and performance on the health system was hypothesized. The findings revealed that health system sustainability had a negative effect on health–disease status, measured in terms of disease incidence. However, the relationship between health system performance and health–disease status is positive. Furthermore, health system performance mediates the relationship between sustainability and health–disease status. According to our study, if we consider the opposite poles that make up the definition of health–disease status (well-being and disease), this concept is defined more by the incidence of the negative aspect.

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