scholarly journals Efficacy of some insecticides for control of oak lace bug (Corythucha arcuata Say)

Topola ◽  
2021 ◽  
pp. 21-26
Author(s):  
Milan Drekić ◽  
Leopold Poljaković-Pajnik ◽  
Marina Milović ◽  
Branislav Kovačević ◽  
Andrej Pilipović ◽  
...  
Keyword(s):  
North America ◽  
High Efficiency ◽  
Harmful Effect ◽  
Test Results ◽  
Lace Bug ◽  
Lace Bugs ◽  
Active Substances ◽  
New Pest

The oak lace bug (Corythucha arcuata Say) was introduced to Europe from North America in 2000 and was first recorded in Serbia in 2013. It is a very serious oak pest which has harmful effect in both adult and nymph stages of the insect that feeds by sucking the sap on the lower (abaxial) leaf side. As this is a relatively new pest in our country, the possibility of its control by applying insecticides was tested during 2021. The paper presents the test results of three insecticidal active substances: deltamethrin, flonicamid and acetamiprid for the control of oak lace bugs. The insecticide flonicamid did not show sufficient efficacy in the suppression of the oak lace bug, while deltamethrin and acetamiprid have high efficiency for the suppression of the adults and nymphs of the oak lace bug, which recommended them for this purpose.

Evaluation of Selected Cotoneaster spp. for Resistance to Hawthorn Lace Bug

1985 ◽  
Vol 3 (4) ◽  
pp. 156-157
Author(s):  
Peter B. Schultz
Keyword(s):  
The Other ◽  
Lace Bug ◽  
Lace Bugs ◽  
Preference Study ◽  
Dense Pubescence

Four Cotoneaster species were evaluated for resistance to hawthorn lace bug. In a preference study using adults, the lace bugs preferred C. x watereri Exell. ‘Brandekeir’ when compared to the other 3 species, C. lacteus W.W.Sm., C. nitens Rehd. & E.H. Wils. and C. acutifolius Turcz. Significantly fewer nymphs completed development on foliage of C. lacteus than on C. x watereri ‘Brandekeir,’ C. nitens and C. acutifolius. The presence of dense pubescence is suggested as a factor in this reduced development.

In Vitro Screening of Azalea for Resistance to Azalea Lace Bug

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 506b-506
Author(s):  
Carol D. Robacker ◽  
S.K. Braman
Keyword(s):  
Leaf Damage ◽  
In Vitro Screening ◽  
Screening Assay ◽  
Delaware Valley ◽  
In Vitro Techniques ◽  
Culture Tube ◽  
Lace Bug ◽  
Lace Bugs ◽  
Laboratory Bioassays

Azalea lace bug (Stephanitis pyrioides) is the most serious pest on azalea. Results of laboratory bioassays and field evaluations of 17 deciduous azalea taxa have identified three resistant taxa: R. canescens, R. periclymenoides, and R. prunifolium. Highly susceptible taxa are `Buttercup', `My Mary', R. oblongifolium, and the evergreen cultivar `Delaware Valley White'. To determine whether in vitro techniques would have potential value in screening or selecting for resistance, or for the identification of morphological or chemical factors related to resistance, an in-vitro screening assay was developed. In-vitro shoot proliferation was obtained using the medium and procedures of Economou and Read (1984). Shoots used in the bioassays were grown in culture tubes. Two assays were developed: one for nymphs and one for adult lace bugs. To assay for resistance to nymphs, `Delaware Valley White' leaves containing lace bug eggs were disinfested with 70% alcohol and 20% commercial bleach, and incubated in sterile petri plates with moistened filter paper until the nymphs hatched. Five nymphs were placed in each culture tube, and cultures were incubated for about 2 weeks, or until adults were observed. To assay for resistance to adults, five female lace bugs were placed in each culture tube and allowed to feed for 5 days. Data collected on survival and leaf damage was generally supportive of laboratory bioassays and field results. Adult lace bugs had a low rate of survival on resistant taxa. Survival of nymphs was somewhat reduced on resistant taxa.

Ice-active substances associated with Antarctic freshwater and terrestrial photosynthetic organisms

2000 ◽  
Vol 12 (4) ◽  
pp. 418-424 ◽  
Author(s):  
James A. Raymond ◽  
Christian H. Fritsen
Keyword(s):  
Molecular Weight ◽  
North America ◽  
Ice Crystals ◽  
Dry Valleys ◽  
Cyanobacterial Mats ◽  
Cold Environments ◽  
Photosynthetic Organisms ◽  
Eukaryotic Algae ◽  
Dialysis Membranes ◽  
Active Substances

Macromolecular substances that cause pitting and other modifications of growing ice crystals were found to be associated with cyanobacterial mats, eukaryotic algae and mosses from Ross Island and the McMurdo Dry Valleys, Antarctica. Ice-pitting activities were largely retained by dialysis membranes with molecular weight cut-offs of up to 300 kDa. Unlike most aqueous solutes, the ice-active molecules were not excluded from the ice phase during freezing. The ice-pitting activities of each of the samples tested was destroyed by exposure to temperatures between 45 and 65°C, suggesting that they have a protein component. Ice-active substances were not found in cyanobacteria or mosses from temperate climates, but ice-activity was found to be associated with mosses from cold habitats in North America. Although the function of the ice-active substances is not known, their apparent confinement to cold environments suggests that they have a cryoprotective role.

scholarly journals The use of the method of controlling the electrochemical parameters of aqueous solutions to combat complications in the operation of oil field pipelines

2021 ◽  
Vol 225 ◽  
pp. 01008
Author(s):  
Oleg Latypov ◽  
Sergey Cherepashkin ◽  
Dina Latypova
Keyword(s):  
Aqueous Solutions ◽  
Oil And Gas ◽  
High Efficiency ◽  
Oil Field ◽  
Oil Fields ◽  
Control Methods ◽  
Test Results ◽  
Chemical Reagents ◽  
Electrochemical Parameters ◽  
Very High

Corrosion of equipment in the oil and gas complex is a global problem, as it contributes to huge material costs and global disasters that violate the environment. Corrosion control methods used to protect equipment do not always ensure the absolute safety of the operation of oil and gas facilities. Moreover, they are quite expensive. The developed method for controlling the electrochemical parameters of aqueous solutions to combat complications during the operation of oil-field pipelines provides the necessary protection against corrosion. The method is economical and environmentally friendly, since it does not require the use of chemical reagents. The test results have shown a very high efficiency in dealing with complications in oil fields.

scholarly journals Load characteristics of three-plunger pumps for spray seawater fire-fighting

2020 ◽  
pp. 142-146
Author(s):  
В.А. Наумов ◽  
Н.Л. Великанов ◽  
А.В. Тришина
Keyword(s):  
Satisfactory Agreement ◽  
Test Data ◽  
High Efficiency ◽  
Measurement Data ◽  
Fire Fighting ◽  
Test Results ◽  
Hydraulic Characteristics ◽  
Fire Extinguishing ◽  
Load Characteristics ◽  
Low Pressures

Цель статьи – получить эмпирические зависимости для характеристик трехплунжерных противопожарных насосов (ТПН), необходимые для автоматизации расчетов систем тушения пожаров на судах с применением распыленной морской воды. Задачи исследования: проверка непротиворечивости данных испытаний; определение расчетных зависимостей производительности ТПН, к.п.д., затраченной мощности от давления. Проведенный анализ результатов испытаний ТПН подтвердил возможность использования предложенных зависимостей в инженерных расчетах. Данные измерений удовлетворительно согласуются с результатами расчетов, за исключением к.п.д. Отклонение экспериментальных точек от эмпирических зависимостей, скорее всего, связано с занижением значений затраченной мощности на испытаниях при небольших давлениях. Предложено для оценки к.п.д. использовать ранее полученную типовую зависимость. Построены графики для характеристик насоса NP25/41-170S. Пример расчета рабочей точки насосной установки с использованием приближенной гидравлической характеристики водяной пожарной системы судна показал высокую эффективность предложенных методик. The purpose of the article is to obtain empirical dependences for the characteristics of three-plunger fire-fighting pumps (TFP), which are necessary for automating calculations of fire extinguishing systems on ships using sprayed seawater. Research objectives: checking the consistency of test data; determining the calculated dependences of the TFP performance, efficiency, power expended on pressure. The analysis of the TFP test results confirmed the possibility of using the proposed dependencies in engineering calculations. The measurement data are in satisfactory agreement with the results of calculations, with the exception of efficiency. The deviation of experimental points from the empirical dependences is most likely due to an underestimation of the power consumed during tests at low pressures. It is proposed to use the previously obtained typical dependence to estimate the efficiency. Graphs are plotted for the characteristics of the NP25/41-170S pump. An example of calculating the working point of a pumping unit using the approximate hydraulic characteristics of the ship's water fire system showed the high efficiency of the proposed methods.

scholarly journals A new pest of ficus in California: Macrohomotoma gladiata Kuwayama, 1908 (Hemiptera: Psylloidea: Homotomidae), new to North America

Check List ◽  
2016 ◽  
Vol 12 (3) ◽  
pp. 1882 ◽  
Author(s):  
Alessandra Rung
Keyword(s):  
North America ◽  
Diagnostic Features ◽  
First Time ◽  
New Pest

A new psyllid pest of ficus, Macrohomotoma gladiata (Hemiptera: Sternorrhyncha: Psylloidea), is reported for the first time from North America (California, U.S.A.). Notes on another adventive psyllid species that has been collected from ficus in California, Homotoma ficus, are given, together with a list diagnostic features that separate between M. gladiata and H. ficus.

scholarly journals Green Lacewings and Water Sprays for Azalea Lace Bug Control1

2018 ◽  
Vol 36 (4) ◽  
pp. 119-125
Author(s):  
Jana C. Lee ◽  
Barry Finley ◽  
S. Michael Flores ◽  
Katerina Velasco Graham ◽  
J. Megan Woltz ◽  
...  
Keyword(s):  
Biological Control ◽  
Field Trials ◽  
Green Lacewing ◽  
Chrysoperla Rufilabris ◽  
Lace Bug ◽  
Landscape Plants ◽  
Water Sprays ◽  
Lace Bugs ◽  
Sequential Combination ◽  
Application Methods

Abstract The azalea lace bug, Stephanitis pyrioides, is a serious pest of azaleas and rhododendrons which is often controlled by systemic insecticides. However, the efficacy of softer approaches such as biological control and water sprays against this pest on rhododendrons is unknown. Therefore, we tested the commercially available green lacewing predator, Chrysoperla rufilabris, and water sprays on lace bug infestation in one laboratory and four field trials. First, 2nd instar predator larvae were confirmed to consume lace bug nymphs and sometimes adults. Second, tapping predator larvae from hexcel units over dry leaves of potted rhododendrons and shaking loose eggs over wet leaves were reliable application methods. Third, predator larvae released onto potted rhododendrons lowered lace bug counts for two weeks. Fourth, after four bi-weekly applications, plants receiving egg cards or water-sprays had reduced lace bug counts and fewer damaged leaves than control plants. Fifth, landscape plants receiving the sequential combination of water spray followed by predator egg releases had 44 to 90% lower lace bug abundance and fewer damaged leaves than the control. After lace bugs were initially dislodged, hatching predators might have consumed hatching lace bugs. Index words: biological control, Chrysoperla rufilabris (Burmeister), mechanical control, rhododendron, Stephanitis pyrioides (Scott) Species used in this study: Azalea lace bug (Stephanitis pyrioides Scott), green lacewing (Chrysoperla rufilabris Burmeister), Rhododendron (Rhododendron spp.)

scholarly journals Study on the Turbine Vane and Blade for a 1500°C Class Industrial Gas Turbine

1993 ◽  
Author(s):  
S. Amagasa ◽  
K. Shimomura ◽  
M. Kadowaki ◽  
K. Takeishi ◽  
H. Kawai ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Film Cooling ◽  
High Efficiency ◽  
Development Program ◽  
Test Results ◽  
Directionally Solidified ◽  
Barrier Coating ◽  
Turbine Vane ◽  
Nickel Base ◽  
Industrial Gas Turbine

This paper describes the summary of a three year development program for the 1st stage stationary vane and rotating blade for the next generation, 1500°C Class, high efficiency gas turbine. In such a high temperature gas turbine, the 1st turbine vane and blade are the most important hot parts. Full coverage film cooling (FCFC) is adopted for the cooling scheme, and directionally solidified (DS) nickel base super-alloy and thermal barrier coating (TBC) will be used to prolong the creep and thermal fatigue life. The concept of the cooling configuration, fundamental cascade test results and material test results will be presented.

Numerical Simulation and Experimental Study of a Two-Floor Structure Pumping System

2010 ◽  
Author(s):  
Chao Liu ◽  
Yan Jin ◽  
Jiren Zhou ◽  
Fangping Tang
Keyword(s):  
Numerical Simulation ◽  
Simple Structure ◽  
High Efficiency ◽  
Test Results ◽  
Pumping System ◽  
Performance Curves ◽  
The Standard Model ◽  
Floor Structure ◽  
Low Efficiency ◽  
Good Agreement

The two-floor flow passages pumping system with the simple structure is well practical in the Basin of Yangzi River downstream. However, this kind of pumping system has some disadvantages, such as low efficiency, easy to appear submerse vortex in discharge flow passages which causes the unit vibration and does harm to the operating of pump unit. In order to solve these problems, the design scheme with a new curve of diffusing outlet structure and inlet cone put forward, which are used in the renovation of the two-floor flow passages pumping station. With the numerical simulation of the two-floor flow passages pumping system, the flow fields are analyzed, and the external performance curves are obtained. To verify the calculation, a model tests were done using the standard model of pump. The test results are compared with the performance curves of numerical simulation. Good agreement of two results is found in the high efficiency area, which can show the calculation is believable. The new design improves the efficiency of pumping system significantly and eliminates the submerse vortex, also can guarantees the economy and security of operating.

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