scholarly journals Effects of water volume rates on spray deposition and control of tarnished plant bug [Hemiptera : Miridae] in strawberry crops

2005 ◽  
Vol 81 (3) ◽  
pp. 115-122 ◽  
Author(s):  
B. Panneton ◽  
A. Bélanger ◽  
C. Vincent ◽  
M. Piché ◽  
M. Khelifi
Keyword(s):  
Field Experiments ◽  
Population Control ◽  
Spray Deposition ◽  
Water Volume ◽  
Lygus Lineolaris ◽  
Tarnished Plant Bug ◽  
Insecticidal Efficacy ◽  
Before And After ◽  
Insecticidal Treatment ◽  
And Control

Field experiments were performed on the effect of three volumes of application on spray deposition and insecticidal efficacy against the tarnished plant bug (Lygus lineolaris) in two strawberry (Fragaria ananassa) cultivars, Kent and Chambly. The rate of application of malathion was kept constant at 4.5 kg a.i. ha-1 for volumes of application of 500 and 1500 L ha-1. Plant coverage was measured using a fluorescent tracer applied at volumes of application of 500, 1000 and 1500 L ha-1. The tracer was recovered from samples taken from different plant locations and on the ground. Tarnished plant bug populations were evaluated 24 hours before and after insecticidal treatment. When coverage data were normalized for a fixed active ingredient rate, an increase in the volume of application from 500 to 1500 L ha-1 frequently had no effect on the amount of tracer recovered at the various locations. On some occasions, an increase in volume of application resulted in a decrease in the amount of tracer recovered, i.e. leaves at the top and bottom of the canopy (Kent), sepals (Kent). Tarnished plant bug population control was commercially acceptable at 500 and 1500 L ha-1.

Systems Approach to Evaluate Tarnished Plant Bug (Hemiptera: Miridae) Management Practices in Virginia and North Carolina Cotton

2020 ◽  
Vol 113 (5) ◽  
pp. 2223-2234
Author(s):  
Seth J Dorman ◽  
Dominic D Reisig ◽  
Sean Malone ◽  
Sally V Taylor
Keyword(s):  
North Carolina ◽  
Management Practices ◽  
Field Experiments ◽  
Systems Approach ◽  
Economic Benefits ◽  
Cultural Control ◽  
Yield Potential ◽  
Lygus Lineolaris ◽  
Tarnished Plant Bug ◽  
Trade Offs

Abstract Economically damaging infestations of Lygus lineolaris (Palisot de Beauvois), tarnished plant bug, were sporadic in Virginia and North Carolina cotton before 2010. Given the sudden rise of L. lineolaris as an economic pest in these states, regionally specific management practices (i.e., chemical and cultural control) are needed to help producers protect yield potential while minimizing input costs. Field experiments were conducted in Virginia and North Carolina in 2018 and 2019 to 1) determine the effects of various management practices on L. lineolaris density, plant injury (i.e., square retention, internal boll injury), and lint yield, 2) calculate the economic trade-offs between integrated pest management (IPM) systems approach and current management practices for L. lineolaris in these states, and 3) evaluate economic benefits associated with various sampling thresholds. Lygus lineolaris populations peaked mid-season (i.e., August) during cotton flowering in both states. Weekly scouting and applying foliar insecticides when the current University Extension recommended economic threshold was reached was the most critical management treatment in maximizing economic returns. Additional costs among various IPM practices did not translate into significant yield protection and economic gains. Moreover, there were additional economic benefits associated with protecting glabrous and longer maturing varieties in Virginia. Lygus lineolaris density varied significantly between states; therefore, management recommendations should be modified based on the growing region. Results from this study will be used to create an IPM strategy to help cotton producers effectively manage this insect pest in the Southeast.

Antennal and Behavioral Responses of Lygus lineolaris (Palisot de Beauvois) (Heteroptera: Miridae) to Metathoracic Scent Gland Compounds

2007 ◽  
Vol 42 (1) ◽  
pp. 92-104 ◽  
Author(s):  
Qing-He Zhang ◽  
Kamlesh R. Chauhan ◽  
Aijun Zhang ◽  
Gordon L. Snodgrass ◽  
Joseph C. Dickens ◽  
...  
Keyword(s):  
Field Experiments ◽  
Virgin Female ◽  
Behavioral Activity ◽  
Lygus Lineolaris ◽  
Scent Gland ◽  
Tarnished Plant Bug ◽  
Hexyl Butyrate ◽  
Metathoracic Scent Gland ◽  
Negative Effect ◽  
Number Of Males

Hexyl and (E)-2-hexenyl butyrates and (E)-4-oxo-2-hexenal are major components of the metathoracic scent gland (MSG) secretion and aeration samples of many plant bugs (Miridae), including the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois). Laboratory and field experiments were performed (1) to determine the extent to which MSG-produced compounds are detected by antennae of L. lineolaris males and females, and (2) to elucidate the behavioral activity associated with the antennally active MSG compounds. The three major MSG-produced compounds elicited strong antennal responses by both sexes. In Y-track olfactometer tests, attraction of males to virgin females was significantly reduced when a dispenser loaded with hexyl butyrate was placed with the virgin females. Hexyl butyrate tested alone against a blank control significantly repelled males. In the field, ternary and partial binary combinations of these three EAD-active compounds failed to attract either sex, whereas virgin females attracted a significant number of males. However, addition of hexyl butyrate and/or (E)-2-hexenyl butyrate to virgin female-baited traps significantly reduced the number of males caught compared with the level of the blank control traps. This might be due either to a negative effect on pheromone release by the females or direct repellency of males, or both. These MSG compounds may be useful for mating disruption and other pest management tactics against economically important plant bugs.

Diel variations in the effect of spates on mayflies (Ephemeroptera: Baetis)

1992 ◽  
Vol 70 (9) ◽  
pp. 1696-1700 ◽  
Author(s):  
Jill Lancaster
Keyword(s):  
Size Distribution ◽  
Field Experiments ◽  
Apparent Effect ◽  
Short Term ◽  
Creek Water ◽  
Diel Variations ◽  
Before And After ◽  
And Control

Field experiments were carried out to determine whether there are diel variations in the effect of spates on baetid mayflies. Short-term spates were created in experimental streamside channels by pumping filtered creek water into selected channels at various times of day, resulting in three- or four-fold increases in discharge. Drift samples were collected before, during, and after spates; benthic samples were collected before and after. Drift rates of Baetis from channels in spate were higher than controls at all times of day. Natural increases in drift were observed in all channels after sunset, and drift rates from channels in spate were highest at this time. The susceptibility of nymphs to drift from channels was calculated as the ratio of drift densities in spate and control channels. Baetis appeared to be more vulnerable to spates after sunset than at dawn or midday. In unmanipulataed flow, large nymphs occurred most frequently in the drift after sunset. Spates had no apparent effect on the size distribution of nymphs in the drift compared with unmanipulated flows at the same time. These spates were not large enough and (or) long enough to greatly decrease mayfly densities in the benthos. It is notable, however, that benthic densities of Baetis were reduced significantly only by one spate at dusk.

scholarly journals Effect of the Use Lethal Ovitrap to Population Aedes sp

2017 ◽  
Vol 1 (1) ◽  
pp. 20
Author(s):  
Tri Ramadhani ◽  
Bondan Fajar Wahyudi
Keyword(s):  
Population Control ◽  
Total Sample ◽  
Control Group ◽  
P Value ◽  
Before And After ◽  
Quasi Experimental ◽  
The Mean ◽  
The Difference ◽  
And Control ◽  
Experimental Group

<p><em>Dengue vector control has been done in various ways, however, has not been able to obtain optimal </em><em>results. Ovirap use to determine the presence of Aedes sp in a region is often done, but the application </em><em>of lethal ovitrap for population control Aedes sp still rarely done. This study was aimed to assess the </em><em>effect of LO applications on populations of Aedes sp. </em></p><p><em></em><em>This research includes quasi experimental design with a pretest-posttest control group without </em><em>randomization. Research sites in dengue in endemic areas in Banyumas district, with a total sample of </em><em>100 homes in each treatment and control areas. Insecticides used on ovistrip is cypermethrin at a dose </em><em>of 12.5 mg ai/strip. Populations of Aedes sp measured each week for three weeks prior to the </em><em>intervention and twelve weeks during the intervention. The mean density of Aedes sp compared before </em><em>and after intervention and between treatment and control areas.</em><br /><em>The study showed the difference of mosquito densities before and after the intervention in the </em><em>experimental group was 0,07 ( p-value 0.044), whereas the control group was 0.037 (p-value 0.341). </em><em>LO use with the addition of insecticide active ingredient cypermetrin on ovistrip impact on the decline </em><em>density of Aedes sp.</em></p>

EFEKTIVITAS METODE DEMONSTRASI DALAM MENINGKATKAN HASIL BELAJAR SISWA SEKOLAH MENENGAH KEJURUAN PADA PENGAJARAN SISTEM KOLOID

2013 ◽  
Vol 19 (1) ◽  
pp. 28
Author(s):  
Hamda Situmorang ◽  
Manihar Situmorang
Keyword(s):  
High School ◽  
High School Students ◽  
Abstract Concept ◽  
Vocational High School ◽  
School Students ◽  
Lecture Method ◽  
Colloid System ◽  
Before And After ◽  
The Right ◽  
And Control

Abstract Implementation of demonstration method in the teaching of chemistry is assigned as the right strategy to improve students’ achievement as it is proved that the method can bring an abstract concept to reality in the class. The study is conducted to vocational high school students in SMKN1 Pargetteng getteng Sengkut Pakfak Barat at accademic year 2013. The teaching has been carried out three cycles on the teaching of chemistry topic of colloid system. In the study, the class is divided into two class, experiment class and control class. The demontration method is used to teach students in experimental class while the teaching in control class is conducted with lecture method. Both are evaluated by using multiple choise tests before and after the teaching procedures, and the ability of students to answer the problems are assigned as students’ achievements. The results showed that demonstration method improved students’ achievement in chemistry. The students in experimental class who are taughed with demonstration method (M=19.08±0.74) have higher achievements compare with control class (M=12.91±2.52), and both are significantly different (tcalculation 22.85 > ttable 1.66). The effectivity of demostration method in experimental class (97%) is found higer compare to conventional method in control class (91%).

Effects of Time and Perceptual Orientation on Actors' and Observers' Attributions

1984 ◽  
Vol 58 (1) ◽  
pp. 23-30
Author(s):  
Donald S. Martin ◽  
Ming-Shiunn Huang
Keyword(s):  
Video Recording ◽  
Control Group ◽  
Control Groups ◽  
Video Recordings ◽  
Before And After ◽  
Perceptual Orientation ◽  
Initial Difference ◽  
Variety Show ◽  
And Control ◽  
Unrelated Variety

The actor/observer effect was examined by Storms in a 1973 study which manipulated perceptual orientation using video recordings. Storms' study was complex and some of his results equivocal. The present study attempted to recreate the perceptual reorientation effect using a simplified experimental design and an initial difference between actors and observers which was the reverse of the original effect. Female undergraduates performed a motor co-ordination task as actors while watched by observers. Each person made attributions for the actor's behaviour before and after watching a video recording of the performance. For a control group the video recording was of an unrelated variety show excerpt. Actors' initial attributions were less situational than observers'. Both actors and observers became more situational after the video replay but this effect occurred in both experimental and control groups. It was suggested the passage of time between first and second recording of attributions could account for the findings and care should be taken when interpreting Storms' (1973) study and others which did not adequately control for temporal effects.

The Effect of Using Flipped Classroom Model to Improve Iraqi EFL Learners’ Pronunciation in English at University Level

2020 ◽  
Vol 1 (40) ◽  
pp. 631-654
Author(s):  
Khaldoon Waleed Husam Al-Mofti
Keyword(s):  
Language Learning ◽  
Flipped Classroom ◽  
Efl Learners ◽  
English Pronunciation ◽  
Before And After ◽  
Quasi Experimental ◽  
University Level ◽  
The University ◽  
And Control ◽  
Experimental Group

For Iraqi EFL learners who are studying English pronunciation in a traditional instruction method often requires more effort and hard work. Thus, using new methods of teaching such as the flipped classroom model (FCM) is necessary to facilitate learning and improve performance. Hence, this study reports on explanatory research that investigates the effect of using the FCM in the teaching of English pronunciation for Iraqi EFL learners at the university level. The study implemented mixed research methods for data collection in a quasi-experimental analysis. Therefore, two tests were conducted on the assigned groups to measure the effect of the FCM before and after the intervention. Besides, a questionnaire and interviews were used on the experiment group students to collect data about their perceptions of the FCM. The study length (lasted)  was 15 weeks and is comprised of 60 students from the department of English, College of Arts at the University of Anbar. The students were divided into two groups, experimental, and control with 30 students in each group. The findings revealed that there was a significant statistical difference between the two groups in favour of the experimental group with better performance, indicating that the FCM has considerably assisted the Iraqi EFL learners to improve their English pronunciation. Moreover, the students expressed their positive feedback and satisfaction on the use of the FCM in their responses to the questionnaire and the interviews. As such, the current study recommends further research to study the effect of applying the FCM in areas and disciplines other than language learning.

Using advanced control, post-denitrification and equalisation to improve the performance of a submerged filter

2000 ◽  
Vol 41 (4-5) ◽  
pp. 177-184 ◽  
Author(s):  
K.H. Sørensen ◽  
D. Thornberg ◽  
K.F. Janning
Keyword(s):  
Energy Consumption ◽  
Total N ◽  
Control Loops ◽  
Effluent Quality ◽  
Advanced Control ◽  
Before And After ◽  
And Control ◽  
Side Flow ◽  
Configuration Control ◽  
Control Post

In 1998, the capacity of the BIOSTYR® submerged biofilter at Nyborg WWTP was extended from 48,000 PE to 60,000 PE including advanced sensor based control, post-denitrification in BIOSTYR® and equalization of side flows. The existing configuration with 8 BIOSTYR® DN/N cells is based on pre-denitrification and an internal recirculation of 600–800%. The extended plant comprises 7 BIOSTYR® DN/N cells with 50–225% recirculation followed by 3 BIOSTYR DN cells for post-denitrification. The advanced control loops include blower control, control of the number of active cells (stand-by), automatic switch to high load configuration, control of the side flow equalization, control of the internal recirculation and control of the external carbon source dosing. In this paper, the achieved improvements are documented by comparing influent and effluent data, methanol and energy consumption from comparable periods before and after the extension. Although the nitrogen load to the plant was increased by 20% after the extension, the effluent quality has improved significantly with a reduction of Total-N from 7–8 mg/l to 3–4 mg/l. Simultaneously, the methanol consumption has been reduced by more than 50% per kg removed nitrogen. The energy consumption remained constant although the nitrogen load was increased by 20% and the inflow by 80%.

Melatonin Improves Erythropoietin Hyporesponsiveness via Suppression of Inflammation

2019 ◽  
Vol 14 (3) ◽  
pp. 203-208
Author(s):  
Evan Noori Hameed ◽  
Haydar F. Hadi AL Tukmagi ◽  
Hayder Ch Assad Allami
Keyword(s):  
Iron Status ◽  
Transferrin Saturation ◽  
Control Group ◽  
Base Line ◽  
Inadequate Response ◽  
Inflammatory Parameters ◽  
Tnf Α ◽  
Before And After ◽  
And Control ◽  
Controlled Clinical Study

Background: Inadequate response to Erythropoietin Stimulating Agents (ESA) despite using relatively larger doses regimen represents a potential risk factor of Cardiovascular (CV) related mortality in addition to health-care economic problems in anemic patients with Chronic Kidney Disease (CKD). Erythropoietin (EPO) hyporesponsiveness related to inflammation has been increased progressively. Melatonin is well known as a potent anti-inflammatory agent. Therefore, the current study was designed to evaluate whether melatonin could improve anemic patients response to EPO. Methods: This single controlled clinical study was carried out in 41 CKD patients with hemoglobin (Hb) levels less than 11g/dl divided randomly in a 1:1 ratio into 2 groups; treatment group who received 5mg melatonin plus their regular treatments and control group who received their regular treatments only. Hematological and iron status parameters include Hb level, serum iron (S. iron), Transferrin Saturation Ratio (TSAT) and serum ferritin (S. ferritin) in addition to inflammatory parameters that include tissue necrotic factor alfa (TNF-α), interleukin-1beta (IL-1β) and interleukin-6 (IL-6) determined before and after 12 weeks of treatment. Results: Melatonin remarkably increases the Hb level with a significant increase in S. iron and TSAT compared to baseline. The elevation of S. iron and TSAT was significantly higher in the melatonin group. Additionally, all inflammatory markers estimated were reduced significantly by melatonin compared to base line and control group. Conclusion: The results of the current study showed that melatonin has an advantageous effect on improving EPO response in anemic patients with CKD.

Obesity management through Ayurveda - A Case Study

2017 ◽  
Vol 2 (4) ◽  
Author(s):  
Dheeraj Kumar Tyagi ◽  
Shivakumar .
Keyword(s):  
Clinical Findings ◽  
Dietary Habit ◽  
Unhealthy Lifestyle ◽  
Lifestyle Management ◽  
Before And After ◽  
Effect Of Treatment ◽  
And Control

Lifestyle disorders are one of the biggest threats for the population living unhealthy lifestyle. Sthoulya (Obesity) is one such disorder which creates lot of physical as well as mental disorder to the sufferer. Due to changing lifestyle, comforts and dietary habit lots of individuals changed their life totally. Obesity is a growing disease in developed and developing countries. Prevalence is drastically hike in past few years. Ayurveda, the science of life with which we can manage and control lots of lifestyle disorders. Focusing on dietary and lifestyle management along with treatment, we can overcome the hazards of obesity which is growing in a uncontrolled manner. The available data is based on the clinical findings only. Aim and objective: To assess the effect of “Guru Cha Atarpanam Chikitsa” in the management of Sthoulya. Setting: Swastharakshana evam Yoga, OPD and IPD, SDMCAH, Hassan. Method: Udwarthana, Parisheka, Shamana Aushadhis, Ahara, and Vihara was followed within the treatment duration and effect of treatment was assessed before and after treatment, advised for follow up. Results: The treatment adopted is effective in the management of Sthoulya and to improve the quality of life.

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