Epidemiology and Control of Citrus Greasy Spot in Different Citrus-Growing Areas in Florida

Greasy spot, caused by Mycosphaerella citri, causes defoliation and yield losses on grapefruit in all areas of Florida, but is more severe in southwest Florida and the east coast than in central Florida. The amount of leaf litter, numbers of ascospores produced, and severity of greasy spot on trap plants were monitored throughout 1997 and 1998 in Immokalee (southwest Florida) and Lake Alfred (central Florida). Leaf litter and ascospore production were greatest from March to July in both locations, with little litter and few ascospores thereafter. Ascospore production occurred earlier in Immokalee than in Lake Alfred in both years. Disease on trap plants was moderate to severe throughout the year except from November to February. Large numbers of ascospores produced early in the year when conditions were less favorable resulted in the same disease severity levels as low numbers of ascospores produced later in the year when environmental conditions were favorable. Greater greasy spot severity in southwest Florida, compared with central Florida, is more likely due to higher rainfall and warmer winter temperatures than to differences in time of infection. Single annual copper fungicide applications were made each month from April to August in 1998 and 1999 in LaBelle (southwest Florida), Ft. Pierce (east coast), and Lake Alfred to determine the most effective time of application. Two two-spray treatments, May + July and June + August, were also evaluated in 1999. A single copper fungicide application in June provided the most consistently effective control across all locations. The June + August two-spray treatment was very effective in disease control, but usually no better than a well-timed single application.

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Survey and control of small mammal populations on two hardwood plantations in southern Ontario

The Forestry Chronicle ◽

10.5558/tfc50181-5 ◽

1974 ◽

Vol 50 (5) ◽

pp. 181-185 ◽

Cited By ~ 3

Author(s):

Andrew Radvanyi

Keyword(s):

Small Mammal ◽

Late Summer ◽

Control Measures ◽

Effective Control ◽

Southern Ontario ◽

Live Trapping ◽

Surrounding Areas ◽

And Control ◽

Rodent Populations ◽

Ingredient Cost

Live trapping and tagging methods were employed to assess small mammal populations within two hardwood plantations in southern Ontario. Excessive girdling damage in past years to young planted trees necessitated an evaluation of rodent populations and development of effective control measures. The application of an anticoagulant rodenticide to oat groats bait broadcast over the study area at an ingredient cost of approximately three dollars per acre virtually wiped out the small mammals. Reinvasion from surrounding areas was, however, fairly rapid, particularly during late summer. Further research on longer term control measures using poisoned bait feeder stations is recommended.

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The Effect of Trifluralin Applied Preplant on Grass Weed Control and Establishment and Yield of Barley (Hordeum vulgare)

Weed Technology ◽

10.1017/s0890037x00045346 ◽

1997 ◽

Vol 11 (3) ◽

pp. 515-519 ◽

Cited By ~ 3

Author(s):

Julio A. Scursoni ◽

Emilio H. Satorre

Keyword(s):

Weed Control ◽

Field Experiments ◽

Herbicide Application ◽

Planting Pattern ◽

Weed Density ◽

Time Of Application ◽

Density And Biomass ◽

And Control ◽

Crop Planting ◽

Grass Weed

The objective of this paper was to evaluate the effect of preplant applications of trifluralin on barley stand and yield, and control of grass weeds in field experiments during 1992 and 1993. Factors examined were: (1) crop planting patterns (conventional drill with rows 15 cm apart and deep-seeder drill with rows 25 cm apart), (2) herbicide application times (22 d before sowing and immediately before sowing), and (3) herbicide application. During 1993, hand-weeded plots also were established. Trifluralin applied preplant at 528 g ai/ha reduced weed density and biomass. Weed control was higher under conventional planting than under the deep planting pattern, and there was no effect of the time of application on herbicide efficacy. There was no herbicide injury to the crop, and grain yield was higher in treated than in untreated plots due to successful weed control.

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Confirmation and Control of HPPD-Inhibiting Herbicide–Resistant Waterhemp (Amaranthus tuberculatus) in Nebraska

Weed Technology ◽

10.1017/wet.2016.4 ◽

2017 ◽

Vol 31 (1) ◽

pp. 67-79 ◽

Cited By ~ 26

Author(s):

Maxwel C. Oliveira ◽

Amit J. Jhala ◽

Todd Gaines ◽

Suat Irmak ◽

Keenan Amundsen ◽

...

Keyword(s):

Dose Response ◽

Field Conditions ◽

Effective Control ◽

Herbicide Resistant ◽

Greenhouse Experiments ◽

Amaranthus Tuberculatus ◽

Sites Of Action ◽

And Control ◽

Herbicide Programs

Field and greenhouse experiments were conducted in Nebraska to (1) confirm the 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting resistant-waterhemp biotype (HPPD-RW) by quantifying the resistance levels in dose-response studies, and (2) to evaluate efficacy of PRE-only, POST-only, and PRE followed by POST herbicide programs for control of HPPD-RW in corn. Greenhouse dose-response studies confirmed that the suspected waterhemp biotype in Nebraska has evolved resistance to HPPD-inhibiting herbicides with a 2- to 18-fold resistance depending upon the type of HPPD-inhibiting herbicide being sprayed. Under field conditions, at 56 d after treatment, ≥90% control of the HPPD-RW was achieved with PRE-applied mesotrione/atrazine/S-metolachlor+acetochlor, pyroxasulfone (180 and 270 g ai ha−1), pyroxasulfone/fluthiacet-methyl/atrazine, and pyroxasulfone+saflufenacil+atrazine. Among POST-only herbicide programs, glyphosate, a premix of mesotrione/atrazine tank-mixed with diflufenzopyr/dicamba, or metribuzin, or glufosinate provided ≥92% HPPD-RW control. Herbicide combinations of different effective sites of action in mixtures provided ≥86% HPPD-RW control in PRE followed by POST herbicide programs. It is concluded that the suspected waterhemp biotype is resistant to HPPD-inhibiting herbicides and alternative herbicide programs are available for effective control in corn. The occurrence of HPPD-RW in Nebraska is significant because it limits the effectiveness of HPPD-inhibiting herbicides.

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Comparative Studies on the Effect of Adjuvants with Urea to Reduce the Overwintering Inoculum of Venturia inaequalis

Plant Disease ◽

10.1094/pdis-06-18-1014-re ◽

2019 ◽

Vol 103 (3) ◽

pp. 531-537 ◽

Cited By ~ 1

Author(s):

Janna Beckerman ◽

Chelsi Abbott

Keyword(s):

Leaf Litter ◽

Litter Decomposition ◽

Comparative Studies ◽

Venturia Inaequalis ◽

Apple Scab ◽

Organic Surfactant ◽

Comparable Performance ◽

Improved Sanitation ◽

Litter Degradation ◽

Ascospore Production

A 2-year study on the use of organic and conventional adjuvants alone, or mixed with urea, was conducted for management of overwintering inoculum of the apple scab pathogen, Venturia inaequalis. Select adjuvants (LI 700, Bond Max, Latron B-1956, and Organic Wet Betty [OWB]) have the potential to hasten urea-driven leaf litter decomposition and reduce V. inaequalis overwintering inoculum comparable to urea, and that one organic surfactant could perform the same level of leaf decomposition as urea. Combinations of adjuvants with urea significantly improved leaf litter degradation compared with urea alone, concomitant with reducing the number of pseudothecia present and pseudothecium fertility. We demonstrate that the combination of urea with Bond Max or OWB reduced pseudothecia fertility and ascospore production to less than 5% in the remaining pseudothecia, a significantly greater reduction than with urea alone. These results suggest that conventional growers combine urea with Bond Max or OWB to more effectively reduce overwintering inoculum, and that the adjuvant OWB can provide organic growers with comparable performance to urea used in conventional orchards for improved sanitation.

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Detection and Control Bacteria Cause Grain Rot Burkholderia glumae on Rice

Jurnal Perlindungan Tanaman Indonesia ◽

10.22146/jpti.37755 ◽

2019 ◽

Vol 23 (2) ◽

pp. 163

Author(s):

Syahri Syahri ◽

Renny Utami Somantri ◽

Priatna Sasmita

Keyword(s):

Rainfall Intensity ◽

Effective Control ◽

Burkholderia Glumae ◽

Physiological Factors ◽

Tropical Area ◽

Resistant Varieties ◽

Central Production ◽

Production Areas ◽

And Control ◽

Group 1

Burkholderia glumae, before mid-2018, is categorized as plant quarantine pest A2 Group 1 that its existence has been detected in Indonesia. B. glumae has been known to spread in the central production of rice in Java, Sumatra, Borneo dan Sulawesi. This review aimed to explain the strategies for B. glumae detection through its characteristics and to prevent the divergence of this bacterium in Indonesia. The previous studies reported that the bacteria could reduce yield up to 75% and caused the decrease of weight-grain or the increase of empty grain. The disease intensity is affected by environmental and physiological factors such as warm temperature at nighttime and high rainfall intensity. The optimum temperature for the development of the disease is 30–35°C. Moreover, the pathogen could survive at a temperature of 41°C. The tropical area of 32-36°C are suitable for B. glumae. Recently, the effective control of the disease in the field has not been found yet. Meanwhile, early detection of the disease is not yet determined, even though it is necessary to prevent its spread in rice cultivation in Indonesia. Detection of the disease by Agricultural Quarantine Agency as a frontline is needed to check the entry of the disease carried by the import activities of the seed. Detection in the suspected field by protection institutes through frequent surveillance in central production areas of rice should be considered as an important task.. The effective techniques to prevent B. glumae are the use of resistant varieties, the practice of seed treatments (using antibacterial, bactericide, heat treatment or plant extract), and the application of oxolinic acid to the crops.

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Assessing the Dynamics and Control of Droplet- and Aerosol-Transmitted Influenza Using an Indoor Positioning System

10.1101/130658 ◽

2017 ◽

Cited By ~ 1

Author(s):

Timo Smieszek ◽

Gianrocco Lazzari ◽

Marcel Salathé

Keyword(s):

Wireless Sensors ◽

Public Spaces ◽

Mitigation Strategies ◽

Effective Control ◽

Positioning System ◽

Close Physical Proximity ◽

Close Proximity ◽

Dynamics And Control ◽

And Control ◽

Indoor Positioning System

ABSTRACTThere is increasing evidence that aerosol transmission is a major contributor to the spread of influenza. Despite this, virtually all studies assessing the dynamics and control of influenza assume that it is transmitted solely through direct contact and large droplets, requiring close physical proximity. Here, we use wireless sensors to measure simultaneously both the location and close proximity contacts in the population of a US high school. This dataset, highly resolved in space and time, allows us to model both droplet and aerosol transmission either in isolation or in combination. In particular, it allows us to computationally assess the effectiveness of overlooked mitigation strategies such as improved ventilation that are available in the case of aerosol transmission. While the effects of the type of transmission on disease outbreak dynamics appear to be weak, we find that good ventilation could be as effective in mitigating outbreaks as vaccinating the majority of the population. In simulations using empirical transmission levels observed in households, we find that bringing ventilation to recommended levels has the same mitigating effect as a vaccination coverage of 50% to 60%. Our results therefore suggest that improvements of ventilation in public spaces could be an important and easy-to-implement strategy supplementing vaccination efforts for effective control of influenza spread.

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Effective control measures limited measles outbreak after extensive nosocomial exposures in January-February 2008 in Gothenburg, Sweden

Eurosurveillance ◽

10.2807/ese.13.30.18937-en ◽

2008 ◽

Vol 13 (30) ◽

Author(s):

P Follin ◽

L Dotevall ◽

M Jertborn ◽

Y Khalid ◽

J Å Liljeqvist ◽

...

Keyword(s):

Vaccination Coverage ◽

Control Measures ◽

Effective Control ◽

Imported Case ◽

Measles Outbreak ◽

Measles Outbreaks ◽

Rubella Vaccination ◽

And Control

In January-February 2008, one imported case of measles initiated a series of exposures with around 380 nosocomial secondary contacts. Susceptible individuals were traced early and control measures were initiated that managed to limit the consequences considerably. Only four secondary cases were identified by the end of March. This minor outbreak illustrates the importance and efficiency of early control measures as well as the fact that the risk of measles outbreaks still exists in a country that has high measles, mumps, rubella vaccination coverage among children.

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Analysis and Control of Unknown In-Vehicle Network System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.184-185.1521 ◽

2012 ◽

Vol 184-185 ◽

pp. 1521-1525

Author(s):

Yu En Wu ◽

Yu Hui Hu ◽

Ya Ying Jin ◽

Jun Qiang Xi

Keyword(s):

Dynamic Analysis ◽

Static Analysis ◽

Effective Control ◽

Hybrid Powertrain ◽

Verification Method ◽

Gateway System ◽

Powertrain System ◽

Analytical Protocol ◽

Key Aspects ◽

And Control

A CAN-Bus protocol analysis and verification method with three key aspects which are static analysis, dynamic analysis and verification &control is put forward. Static analysis ascertains the communication information of each node by bus residual method; Synchronous contrast method is put in use to obtain practical and effective control protocol in the dynamic analysis; Verification &control is to verify the correctness of the analytical protocol and to achieve the control of the critical subsystems by bus gateway system. This scheme has been used to analyze a foreign parallel hybrid powertrain system, and it proves the correctness of the designed static analysis and dynamic analysis, the applicability of verification &control.

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Dynamics of bed bug infestations and control under disclosure policies

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1814647116 ◽

2019 ◽

Vol 116 (13) ◽

pp. 6473-6481 ◽

Cited By ~ 5

Author(s):

Sherrie Xie ◽

Alison L. Hill ◽

Chris R. Rehmann ◽

Michael Z. Levy

Keyword(s):

Cost Benefit ◽

Control Policy ◽

Spillover Effects ◽

The United States ◽

Effective Control ◽

Bed Bugs ◽

Bed Bug ◽

Highly Nonlinear ◽

Public Health Practitioners ◽

And Control

Bed bugs have reemerged in the United States and worldwide over recent decades, presenting a major challenge to both public health practitioners and housing authorities. A number of municipalities have proposed or initiated policies to stem the bed bug epidemic, but little guidance is available to evaluate them. One contentious policy is disclosure, whereby landlords are obligated to notify potential tenants of current or prior bed bug infestations. Aimed to protect tenants from leasing an infested rental unit, disclosure also creates a kind of quarantine, partially and temporarily removing infested units from the market. Here, we develop a mathematical model for the spread of bed bugs in a generalized rental market, calibrate it to parameters of bed bug dispersion and housing turnover, and use it to evaluate the costs and benefits of disclosure policies to landlords. We find disclosure to be an effective control policy to curb infestation prevalence. Over the short term (within 5 years), disclosure policies result in modest increases in cost to landlords, while over the long term, reductions of infestation prevalence lead, on average, to savings. These results are insensitive to different assumptions regarding the prevalence of infestation, rate of introduction of bed bugs from other municipalities, and the strength of the quarantine effect created by disclosure. Beyond its application to bed bugs, our model offers a framework to evaluate policies to curtail the spread of household pests and is appropriate for systems in which spillover effects result in highly nonlinear cost–benefit relationships.

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Yellow Nutsedge (Cyperus esculentus) Competition and Control in Corn (Zea mays)

Weed Science ◽

10.1017/s0043174500043435 ◽

1979 ◽

Vol 27 (1) ◽

pp. 32-37 ◽

Cited By ~ 38

Author(s):

E. W. Stoller ◽

L. M. Wax ◽

F. W. Slife

Keyword(s):

Zea Mays ◽

Control Measures ◽

Effective Control ◽

Yield Reduction ◽

Cyperus Esculentus ◽

Yellow Nutsedge ◽

Effective Combination ◽

Percentage Yield ◽

Hand Weeding ◽

And Control

Competition of yellow nutsedge (Cyperus esculentusL.) with corn (Zea maysL.) was evaluated in the field at various yellow nutsedge densities over a 3-yr period. A relationship between yellow nutsedge density (shoots/m2) and percentage yield reduction revealed an 8% yield reduction for every 100 shoots/m2. Two 3-yr studies were conducted to determine the most effective combination of preplant-incorporated, postemergence, or postemergence-directed treatments for yellow nutsedge control in corn. The preplant incorporated treatments were alachlor [2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide], EPTC (S-ethyl dipropylthiocarbamate), or nothing; postemergence treatments were bentazon [3-isopropyl-1H-2,1,3-benzothiadiazin-(4) 3H-one 2,2-dioxide], two cultivations, or nothing; and the postemergence-directed treatments were ametryn [2-(ethylamino)-4-(isopropylamino)-6-(methylthio)-s-triazine] or nothing. One preplant-incorporated treatment of EPTC or alachlor prevented yield reductions from yellow nutsedge competition. When no control was practiced, yields were reduced 17% in a moderate yellow nutsedge infestation (initially infested with 300 tubers/m2) and 41% in a heavy infestation (initially infested with 1200 tubers/m2). Yields were reduced 7 to 8% in the moderate infestation when no preplant-incorporated treatments were used regardless of whether postemergence or postemergence-directed treatments were also used. After 1 yr, all control measures resulted in less tuber density than no control measures, but all control treatments had essentially similar tuber densities. After the second year, several herbicide treatments were as effective as hand weeding in reducing tuber density. At least 2 yr of effective control treatments were required to reduce tubers to 20% of the original density, and 3 yr of treatment to reduce the density to 15% of the original density. No combination of treatments, including hand weeding, eliminated tubers after 3 yr.

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