Joint Action of Disease Control Measures: A Case Study of Alternaria Leaf Blight of Carrot

The efficacy of chemical (i.e., foliar fungicide sprays), genetic (i.e., moderately resistant cultivars), and cultural (i.e., drip-irrigation system) control measures was quantified individually and in combination in the management of Alternaria dauci, the causal agent of Alternaria leaf blight of carrot. Whereas host resistance and drip irrigation affected both the time of disease onset and the rate of disease progression, chemical control affected only the latter. In all cases, a single control measure did not provide an acceptable level of disease suppression. Control efficacy values (based on the relative area under the disease progress curve) for chemical, genetic, and cultural control were 58 ± 11, 39 ± 20, and 60 ± 22%, respectively (values are means ± standard error). By contrast, implementing two control measures concurrently always improved disease suppression significantly compared with the individual measures. Control efficacy values were 91 ± 8% for the integration of chemical and genetic measures and 82 ± 23% for the integration of chemical and cultural measures. Moreover, yields in plots protected by two control measures simultaneously were higher by 10.1 to 28.6 t/ha than those in the respective plots protected by single measures. The joint effect of chemical control and host resistance was additive, whereas that of chemical control and drip irrigation was synergistic in most cases. A literature review was performed to determine if these findings represent a general relationship between chemical and genetic, and chemical and cultural measures. Based on 19 reviewed cases, it was concluded that additive effects are the rule and synergistic or antagonistic effects are the exception. Synergistic effects of two control measures were observed when one control measure improved the efficacy of the other directly or when one control measure induced host resistance or predisposed the pathogen to increased susceptibility. These results may enable a more effective selection of candidate control measures for integration in the future.

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Mechanical and physical control in apple orchards as preventative fungal disease management

International Journal of Horticultural Science ◽

10.31421/ijhs/22/1-2./1178 ◽

2016 ◽

Vol 22 (1-2) ◽

Author(s):

I. J. Holb

Keyword(s):

Disease Management ◽

Leaf Litter ◽

Chemical Control ◽

Fungal Disease ◽

Control Measures ◽

Control Methods ◽

Control Efficacy ◽

Inoculum Sources ◽

Physical Control ◽

Labour Costs

In this minreview, mechanical and physical control against apple fungal diseases among non-chemical control approaches were summarized. This overview listed five groups of mechanical and physical control methods: pruning, removal of inoculum sources, shredding of leaf litter, burying of inoculum sources and flaming of leaf litter. These methods were shown to reduce succesfully infection potential of inoculum sources in orchards and these non-chemical control measures are one of the most essential approaches for preventative fungal disease management. However, most of these methods are not widely spread in the apple-growing practice due to relatively low control efficacy, medium to high labour costs and/or time limits during the season.

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Optimization of Chemical Suppression of Alternaria dauci, the Causal Agent of Alternaria Leaf Blight in Carrots

Plant Disease ◽

10.1094/pdis.2001.85.11.1149 ◽

2001 ◽

Vol 85 (11) ◽

pp. 1149-1156 ◽

Cited By ~ 22

Author(s):

E. Ben-Noon ◽

D. Shtienberg ◽

E. Shlevin ◽

H. Vintal ◽

A. Dinoor

Keyword(s):

Field Experiments ◽

Threshold Model ◽

Disease Onset ◽

Leaf Blight ◽

Copper Hydroxide ◽

Control Efficacy ◽

Alternaria Leaf Blight ◽

Major Constraint ◽

Action Threshold ◽

Alternaria Dauci

Alternaria leaf blight, caused by Alternaria dauci, is a major constraint to carrot production in Israel. Israeli carrot growers apply prophylactic sprays at 3- to 10-day intervals throughout the season until harvest, up to 30 sprays in a growing season. In this study, we attempted to optimize the chemical suppression of the disease, in order to reduce fungicide use. The efficacy of nine fungicides was determined in two field experiments. All fungicides reduced disease severity, but there were significant differences in efficacy among them. The most effective were difenoconazole and chlorothalonil; less effective were copper hydroxide, tebuconazole, trifloxystrobin, and mancozeb; the least effective in our experiments were flutrifol, propineb, and iprodione. The effect of the time of spray initiation on fungicide efficacy was determined in three field experiments. Qualitative (analysis of variance) and quantitative (regression) analyses of the data revealed that initiating sprays after disease onset reduced control efficacy. Thus, an action threshold model could not be developed for A. dauci in carrots. The time before harvest at which sprays could be terminated was tested in two field experiments and it was found that terminating sprays 14 days before harvest did not significantly affect the overall control efficacy. The main conclusions derived from these experiments were tested and corroborated in two additional field experiments.

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Bacterial Spot of Pepper

EDIS ◽

10.32473/edis-pp362-2021 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Camille McAvoy ◽

Pamela Roberts ◽

Jeffrey B. Jones

Keyword(s):

Plant Pathology ◽

Disease Management ◽

Host Resistance ◽

Chemical Control ◽

Control Measures ◽

Bacterial Spot ◽

Causal Organism ◽

Disease Cycle ◽

Fact Sheet ◽

Chile Peppers

Bacterial spot, caused by three species of Xanthomonas, is a limiting disease problem on all peppers. This new 4-page fact sheet provides information on symptoms, causal organism and host resistance, disease cycle and epidemiology, and disease management (including cultural and sanitation practices, chemical control measures and the use of Actigard® in chile peppers). Written by Camille McAvoy, Pamela Roberts, and Jeffrey Jones, and published by the UF/IFAS Plant Pathology Department.https://edis.ifas.ufl.edu/pp362

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Characterizing the effectiveness of COVID-19 mitigation measures: A data-centric approach (Preprint)

10.2196/preprints.21321 ◽

2020 ◽

Author(s):

Lukman Olagoke ◽

Ahmet E. Topcu

Keyword(s):

Control Measure ◽

Control Measures ◽

World Health ◽

Mitigation Measures ◽

Effective Control ◽

The World ◽

Decision Making Processes ◽

And Performance ◽

Health Organization ◽

The Impact

BACKGROUND COVID-19 represents a serious threat to both national health and economic systems. To curb this pandemic, the World Health Organization (WHO) issued a series of COVID-19 public safety guidelines. Different countries around the world initiated different measures in line with the WHO guidelines to mitigate and investigate the spread of COVID-19 in their territories. OBJECTIVE The aim of this paper is to quantitatively evaluate the effectiveness of these control measures using a data-centric approach. METHODS We begin with a simple text analysis of coronavirus-related articles and show that reports on similar outbreaks in the past strongly proposed similar control measures. This reaffirms the fact that these control measures are in order. Subsequently, we propose a simple performance statistic that quantifies general performance and performance under the different measures that were initiated. A density based clustering of based on performance statistic was carried out to group countries based on performance. RESULTS The performance statistic helps evaluate quantitatively the impact of COVID-19 control measures. Countries tend show variability in performance under different control measures. The performance statistic has negative correlation with cases of death which is a useful characteristics for COVID-19 control measure performance analysis. A web-based time-line visualization that enables comparison of performances and cases across continents and subregions is presented. CONCLUSIONS The performance metric is relevant for the analysis of the impact of COVID-19 control measures. This can help caregivers and policymakers identify effective control measures and reduce cases of death due to COVID-19. The interactive web visualizer provides easily digested and quick feedback to augment decision-making processes in the COVID-19 response measures evaluation. CLINICALTRIAL Not Applicable

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Microbial antagonists against plant pathogens in Iran: A review

Open Agriculture ◽

10.1515/opag-2020-0031 ◽

2020 ◽

Vol 5 (1) ◽

pp. 404-440 ◽

Cited By ~ 1

Author(s):

Mehrdad Alizadeh ◽

Yalda Vasebi ◽

Naser Safaie

Keyword(s):

Biological Control ◽

Chemical Control ◽

Plant Disease ◽

Plant Pathogens ◽

Plant Diseases ◽

Agricultural Products ◽

Control Measures ◽

Wide Range ◽

Plant Disease Management ◽

Published Research

AbstractThe purpose of this article was to give a comprehensive review of the published research works on biological control of different fungal, bacterial, and nematode plant diseases in Iran from 1992 to 2018. Plant pathogens cause economical loss in many agricultural products in Iran. In an attempt to prevent these serious losses, chemical control measures have usually been applied to reduce diseases in farms, gardens, and greenhouses. In recent decades, using the biological control against plant diseases has been considered as a beneficial and alternative method to chemical control due to its potential in integrated plant disease management as well as the increasing yield in an eco-friendly manner. Based on the reported studies, various species of Trichoderma, Pseudomonas, and Bacillus were the most common biocontrol agents with the ability to control the wide range of plant pathogens in Iran from lab to the greenhouse and field conditions.

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Using Commercial Compost as Control Measures against Cucumber Root-Rot Disease

Journal of Mycology ◽

10.1155/2013/324570 ◽

2013 ◽

Vol 2013 ◽

pp. 1-13 ◽

Cited By ~ 7

Author(s):

Kamel Kamal Sabet ◽

Magdy Mohamed Saber ◽

Mohamed Adel-Aziz El-Naggar ◽

Nehal Samy El-Mougy ◽

Hatem Mohamed El-Deeb ◽

...

Keyword(s):

Root Rot ◽

Control Measure ◽

Disease Incidence ◽

Pathogenic Fungi ◽

Pythium Ultimum ◽

Control Measures ◽

Infested Soil ◽

Fungal Isolates ◽

Cucumber Root

Five commercial composts were evaluated to suppress the root-rot pathogens (Fusarium solani (Mart.) App. and Wr, Pythium ultimum Trow, Rhizoctonia solani Kuhn, and Sclerotium rolfsii Sacc.) of cucumber plants under in vitro and greenhouse conditions. In vitro tests showed that all tested unautoclaved and unfiltrated composts water extracts (CWEs) had inhibitor effect against pathogenic fungi, compared to autoclaved and filtrated ones. Also, the inhibitor effects of 40 bacteria and 15 fungi isolated from composts were tested against the mycelial growth of cucumber root-rot pathogens. Twenty two bacteria and twelve fungal isolates had antagonistic effect against root-rot pathogens. The antagonistic fungal isolates were identified as 6 isolates belong to the genus Aspergillus spp., 5 isolates belong to the genus Penicillium spp. and one isolate belong to the genus Chaetomium spp. Under greenhouse conditions, the obtained results in pot experiment using artificial infested soil with cucumber root-rot pathogens showed that the compost amended soil reduced the percentage of disease incidence, pathogenic fungi population, and improved the cucumber vegetative parameters as shoot length, root length, fresh weight, and dry weight. These results suggested that composts are consequently considered as control measure against cucumber root-rot pathogens.

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Control (supervisory) measures: innovations of Federal Law “On State Control (Supervision) and Municipal Control in the Russian Federation”

Buhuchet v zdravoohranenii (Accounting in Healthcare) ◽

10.33920/med-17-2106-02 ◽

2021 ◽

pp. 25-32

Author(s):

O.V. Shinkareva ◽

V.A. Dikikh

Keyword(s):

Russian Federation ◽

Control Measure ◽

Control Measures ◽

State Control ◽

Federal Law ◽

Field Inspection ◽

Control Actions ◽

The Russian Federation

The article is devoted to the analysis of the types of control measures that will be carried out in accordance with Federal Law No. 248-FZ of the “On State Control (Supervision) and Municipal Control in the Russian Federation”, the main provisions of which will enter into force on July 1, 2021. This law also applies to the activities of organizations that are subject to licensing. Types of control (supervisory) measures are considered, in particular, control and monitoring procurement, inspection visit, raid inspection, documentary and field inspection, as well as monitoring compliance with mandatory requirements and field examination. The essence of each type of control measure, the basis for carrying out the measures, control actions that can be used in their implementation are analyzed.

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Characterization of Antagonistic Bacillus methylotrophicus Isolated From Rhizosphere and Its Biocontrol Effects on Maize Stalk Rot

Phytopathology ◽

10.1094/phyto-07-18-0220-r ◽

2019 ◽

Vol 109 (4) ◽

pp. 571-581 ◽

Cited By ~ 9

Author(s):

Xingkai Cheng ◽

Xiaoxue Ji ◽

Yanzhen Ge ◽

Jingjing Li ◽

Wenzhe Qi ◽

...

Keyword(s):

Biochemical Characterization ◽

Disease Incidence ◽

Field Trials ◽

Control Measures ◽

Disease Suppression ◽

Effective Control ◽

Stalk Rot ◽

Bacillus Methylotrophicus ◽

Transmission Electron ◽

Potential Biocontrol Agent

Stalk rot is one of the most serious and widespread diseases in maize, and effective control measures are currently lacking. Therefore, this study aimed to develop a new biological agent to manage this disease. An antagonistic bacterial strain, TA-1, was isolated from rhizosphere soil and identified as Bacillus methylotrophicus based on morphological and biochemical characterization and 16S ribosomal RNA and gyrB gene sequence analyses. TA-1 exhibited a strong antifungal effect on the growth of Fusarium graminearum mycelium, with 86.3% inhibition at a concentration of 108 CFU per ml. Transmission electron microscopy showed that TA-1 could disrupt the cellular structure of the fungus, induce necrosis, and degrade the cell wall. Greenhouse and field trials were performed to evaluate the biocontrol efficacy of TA-1 on maize stalk rot, and the results of greenhouse experiment revealed that the bacterium significantly reduced disease incidence and disease index. Seeds treated with a 108 CFU ml−1 cell suspension had the highest disease suppression at 86.8%. Results of field trials show that seed bacterization with TA-1 could not only reduce maize stalk rot incidence but also increase maize height, stem diameter, and grain yield. The lipopeptide antibiotics were isolated from the culture supernatants of TA-1 and identified as surfactins and iturins. Consequently, B. methylotrophicus TA-1 is a potential biocontrol agent against maize stalk rot.

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SELF-REPORTED MALARIA AND MOSQUITO AVOIDANCE IN RELATION TO HOUSEHOLD RISK FACTORS IN A KENYAN COASTAL CITY

Journal of Biosocial Science ◽

10.1017/s0021932005007182 ◽

2005 ◽

Vol 37 (6) ◽

pp. 761-771 ◽

Cited By ~ 12

Author(s):

JOSEPH KEATING ◽

KATE MACINTYRE ◽

CHARLES M. MBOGO ◽

JOHN I. GITHURE ◽

JOHN C. BEIER

Keyword(s):

Rural Areas ◽

Mosquito Control ◽

Control Measure ◽

Control Measures ◽

Level Control ◽

Cross Sectional Survey ◽

Cross Sectional ◽

Household Level ◽

Household Factors ◽

History Of

A geographically stratified cross-sectional survey was conducted in 2002 to investigate household-level factors associated with use of mosquito control measures and self-reported malaria in Malindi, Kenya. A total of 629 households were surveyed. Logistic regressions were used to analyse the data. Half of all households (51%) reported all occupants using an insecticide-treated bed net and at least one additional mosquito control measure such as insecticides or removal of standing water. Forty-nine per cent reported a history of malaria in the household. Of the thirteen household factors analysed, low (OR=0·23, CI 0·11, 0·48) and medium (OR=0·50, CI 0·29, 0·86) education, mud–wood–coral (OR=0·0·39, CI 0·24, 0·66) and mud block–plaster (OR=0·47, CI 0·25, 0·87) wall types, farming (OR=1·38, CI 1·01, 1·90) and travel to rural areas (OR=0·48, CI 0·26, 0·91) were significantly associated with the use of mosquito control, while controlling for other covariates in the model. History of reported malaria was not associated with the use of mosquito control (OR=1·22, CI 0·79, 1·88). Of the thirteen covariates analysed in the second model, only two household factors were associated with history of malaria: being located in the well-drained stratum (OR=0·49, CI 0·26, 0·96) and being bitten while in the house (OR=1·22, CI 0·19, 0·49). These results suggest that high socioeconomic status is associated with increased household-level mosquito control use, although household-level control may not be enough, as many people are exposed to biting mosquitoes while away from the house and in areas that are more likely to harbour mosquitoes.

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