Gene expression of detoxification enzymes in insecticide-resistant and insecticide-susceptible Bemisia tabaci strains after diafenthiuron exposure

2016 ◽  
Vol 154 (4) ◽  
pp. 742-753 ◽  
Author(s):  
B.-Z. ZHANG ◽  
F.-C. KONG ◽  
R.-K. CUI ◽  
X.-N. ZENG
Keyword(s):  
Bemisia Tabaci ◽  
Resistance Management ◽  
Detoxification Enzymes ◽  
Mechanisms Of Resistance ◽  
Glutathione S Transferase ◽  
Over Expression ◽  
Cytochrome P450 Genes ◽  
And Control ◽  
Detoxification Gene ◽  
Selection Of

SUMMARYThe B-biotype of Bemisia tabaci (Homoptera: Aleyrodidae) has become extremely resistant to commonly used insecticides in China. To further explore the mechanisms of resistance to diafenthiuron, the diafenthiuron induction profiles of carboxylesterase (COE1), glutathione S-transferase (GST) and seven cytochrome P450 genes in both resistant (R-DfWf) and susceptible (S-Lab) strains were characterized. The detoxification genes GST, CYP6CX4, CYP6DW3, CYP6DZ6 and CYP9F, which are known to be constitutively over-expressed in the R-DfWf strain, were significantly upregulated in R-DfWf and S-Lab strains exposed to diafenthiuron at LC50 compared with their levels in strains treated with distilled water (controls); however, CYP6CX1, another detoxification gene, was not upregulated. The upregulation was more pronounced in the R-DfWf strain than in the S-Lab strain exposed to different concentrations of diafenthiuron (LC10 or LC50). Interestingly, COE1, CYP6CM1 and CYP6A, which are not constitutively over-expressed in the R-DfWf strain, were all significantly upregulated after exposure to diafenthiuron. Similarly, significant differences in the expression of these detoxification genes, with the exception of CYP6CM1 in the S-Lab strain, were also observed after exposure to diafenthiuron. However, the induction of CYP6A and COE1 was more pronounced in the S-Lab strain than in the R-DfWf strain after treatment with diafenthiuron at both concentrations, indicating that diafenthiuron induction of CYP6CM1 is specific to the R-DfWf strain, while diafenthiuron induction of the other genes is common to both the R-DfWf and S-Lab strains. These results demonstrate that multiple detoxification genes are co-upregulated in the R-DfWf strain through both constitutive over-expression and induction mechanisms. This knowledge will be useful for rational selection of insecticides for use in resistance management and control of this species.

Field evaluation of different insecticide use strategies as resistance management and control tactics for Bemisia tabaci (Hemiptera: Aleyrodidae)

2002 ◽  
Vol 92 (6) ◽  
pp. 449-460 ◽  
Author(s):  
S.J. Castle ◽  
N.C. Toscano ◽  
N. Prabhaker ◽  
T.J. Henneberry ◽  
J.C. Palumbo
Keyword(s):  
Bemisia Tabaci ◽  
Resistance Management ◽  
Field Evaluation ◽  
Cotton Yield ◽  
Cotton Lint ◽  
Southwestern Usa ◽  
Study Support ◽  
Second Year ◽  
Sequential Treatments ◽  
And Control

AbstractVarious insecticide use strategies including rotations, sequential use, and mixtures were evaluated experimentally on Bemisia tabaci (Gennadius) in California and Arizona (USA) cotton fields. Toxicological responses of adult B. tabaci were measured along with preimaginal densities and cotton yields from plots subjected to different insecticide regimens. Weekly monitoring for susceptibility changes over ten consecutive weeks in four different trials failed to detect significant differences between sequential use and rotation regimens, nor in comparison to the control plots. There were, however, significant differences among study-site locations and between study years as well as significant within-season time effects. Relative infestations in insecticide-treated plots expressed as a percentage of preimaginal densities in control plots indicated that better control was obtained by all insecticide treatments in conjunction with higher susceptibility levels observed in the second year. Lower preimaginal densities of B. tabaci were measured in the rotation treatment in comparison to sequential treatments of endosulfan, chlorpyrifos, or amitraz, but all were less effective than sequential treatments of bifenthrin or the mixture of bifenthrin + endosulfan. Cotton lint yields were inversely related to B. tabaci densities, with highest yields in the bifenthrin and mixture plots and lowest yields in the control plots. Suppression of B. tabaci infestations in insecticide-treated plots relative to untreated control plots also improved under conditions of lower B. tabaci pressure. The increases in cotton yield and susceptibility to insecticides seen in the current study support the trend observed in the southwestern USA of improved management of B. tabaci despite continuing intensive use of insecticides.

scholarly journals First Report on the Mechanisms of Insecticide Resistance in Field Populations of the Small Hive Beetle in Florida

Agriculture ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 559
Author(s):  
Lambert H. B. Kanga ◽  
Walker Marechal ◽  
Anthony Ananga
Keyword(s):  
Insecticide Resistance ◽  
Control Strategies ◽  
Resistance Management ◽  
The United States ◽  
Aethina Tumida ◽  
Small Hive Beetle ◽  
Mechanisms Of Resistance ◽  
Glutathione S Transferase ◽  
Resistance Factors ◽  
Development Of Resistance

The small hive beetle (Aethina tumida Murray) is a serious threat to beekeeping and crops that rely on honeybees for pollination. The small hive beetle not only causes significant damage to honeybees by feeding on pollen and honey, attacking bee brood and causing stored honey to ferment, but also might serve as a vector of diseases. In addition, the small hive beetle has developed resistance to the pyrethroid and organophosphate insecticides registered for control of honeybee pests in the United States. The development of resistance in small hive beetle populations is a great concern to the beekeeping industry; thus, there is an urgent need for strategies to manage that resistance. Therefore, we used synergist probes to determine the mechanisms of resistance in a small hive beetle population to these insecticides. Our studies on the toxicity of insecticides alone or with the synergists piperonyl butoxide (PBO) and S,S,S,-tributyl phosphorotrithionate (DEF) suggested that mixed-function oxidases and esterases were the major resistance factors to these insecticides in a studied population of the small hive beetle. In contrast, there was no synergism with diethyl maleate (DEM), triphenyl phosphate (TPP) and formamidine. Therefore, glutathione-S-transferase, carboxylesterase and target site were not involved in insecticide resistance in the small hive beetle. Rotation of classes of insecticides (with different modes of action) and metabolic synergists were suggested for the development of successful resistance management programs. To the best of our knowledge, this is the first study of the mechanisms of resistance in small hive beetle populations in Florida and suggests an urgent need for alternative control strategies for these serious pests of honeybee colonies.

scholarly journals Comparative Transcriptome Analysis Reveals the Mechanism Related to Fluazinam Stress of Panonychus citri (Acarina: Tetranychidae)

Insects ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 730
Author(s):  
Yi Shang ◽  
Yanbo Wang ◽  
Jianyu Deng ◽  
Xunyue Liu ◽  
Yihao Fang ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Mechanism Of Action ◽  
Good Control ◽  
Glutathione S Transferase ◽  
Control Effect ◽  
Panonychus Citri ◽  
Transcriptomic Sequencing ◽  
Cytochrome P450 Genes ◽  
Differential Expression Genes ◽  
And Control

The use of a large number of chemical acaricides to control these pest mites has led to an increasing problem of pesticide resistance, which has always been the difficulty in integrated pest management (IPM). Fluazinam has a good control effect on Panonychus citri, the serious pest on citrus; however, we only know the mechanism of action of fluazinam as a fungicide and its mechanism of action on mites remains unclear. Through analysis using Illumina high-throughput transcriptomic sequencing and differential expression genes in P. citri treated with fluazinam, 59 cytochrome P450 genes, 23 glutathione s-transferase genes, five carboxylate esterase genes, 11 superoxide dismutase genes and 15 catalase genes were identified. The Gene Ontology enrichment and the enrichment of KEGG results showed that the treatment were enrichment for redox enzyme pathways. Evaluating the efficacy of fluazinam, and analyzing the transcriptome data of P. citri under fluazinam stress, potentially provide a new agent for prevention and control of P. citri, and also preliminary research results for exploring the mechanism of action of fluazinam on P. citri. Given the up-regulated expression levels of genes for Mn-superoxide dismutase and catalase, we speculate that they play an important role in fluazinam-stress action on P. citri.

MODEL OF SOCIAL POTENTIAL OF CHILDHOOD IN THE RUSSIAN REGIONS: THE RESULTS OF EXPERIMENTS

2019 ◽  
pp. 152-162
Author(s):  
A.G. Filipova ◽  
A.V. Vysotskaya
Keyword(s):  
Third Wave ◽  
Russian Regions ◽  
The Third ◽  
Control Factors ◽  
Social Potential ◽  
System Input ◽  
Optimal Values ◽  
Fixed Ideal ◽  
And Control ◽  
Selection Of

The article presents the results of mathematical experiments with the system «Social potential of childhood in the Russian regions». In the structure of system divided into three subsystems – the «Reproduction of children in the region», «Children’s health» and «Education of children», for each defined its target factor (output parameter). The groups of infrastructure factors (education, health, culture and sport, transport), socio-economic, territorial-settlement, demographic and en-vironmental factors are designated as the factors that control the system (input parameters). The aim of the study is to build a model îf «Social potential of childhood in the Russian regions», as well as to conduct experiments to find the optimal ratio of the values of target and control factors. Three waves of experiments were conducted. The first wave is related to the analysis of the dynam-ics of indicators for 6 years. The second – with the selection of optimal values of control factors at fixed ideal values of target factors. The third wave allowed us to calculate the values of the target factors based on the selected optimal values of the control factors of the previous wave.

scholarly journals The dynamic of body and brain co-evolution

2021 ◽  
pp. 105971232199468
Author(s):  
Paolo Pagliuca ◽  
Stefano Nolfi
Keyword(s):  
Morphological Traits ◽  
The Body ◽  
Morphological Variations ◽  
And Control ◽  
Selection Of

We introduce a method that permits to co-evolve the body and the control properties of robots. It can be used to adapt the morphological traits of robots with a hand-designed morphological bauplan or to evolve the morphological bauplan as well. Our results indicate that robots with co-adapted body and control traits outperform robots with fixed hand-designed morphologies. Interestingly, the advantage is not due to the selection of better morphologies but rather to the mutual scaffolding process that results from the possibility to co-adapt the morphological traits to the control traits and vice versa. Our results also demonstrate that morphological variations do not necessarily have destructive effects on robots’ skills.

scholarly journals ProReal®: The ‘good enough’ online alternative to face-to-face Dramatherapy

Dramatherapy ◽  
2021 ◽  
pp. 026306722110208
Author(s):  
Claire Anne Quigley
Keyword(s):  
Ambiguity Tolerance ◽  
Face To Face ◽  
On Line ◽  
And Control ◽  
Selection Of

The Covid-19 restrictions have limited the access of face-to face therapies for many people and continues to effect how Dramatherapists operate. The following article offers reflections around adapting to an on-line medium, focusing more specifically around the software of ProReal. Limitations and considerations are acknowledged, including technological difficulties, computer efficacy, ambiguity tolerance and the need for careful contracting and reassurance of autonomy and control when using on-line platforms. The article ends with a short selection of vignettes from ProReal sessions.

scholarly journals Evaluation and Selection of Integrated Energy System Construction Scheme Equipped with Smart Energy Management and Control Platform Using Single-Valued Neutrosophic Numbers

2021 ◽  
Vol 13 (5) ◽  
pp. 2615
Author(s):  
Junqing Wang ◽  
Wenhui Zhao ◽  
Lu Qiu ◽  
Puyu Yuan
Keyword(s):  
Energy Management ◽  
Evaluation Criteria ◽  
Energy System ◽  
System Construction ◽  
Interval Numbers ◽  
Construction Scheme ◽  
Smart Energy Management ◽  
Integrated Energy System ◽  
And Control ◽  
Selection Of

Since application of integrated energy systems (IESs) has formed a markedly increasing trend recently, selecting an appropriate integrated energy system construction scheme becomes essential to the energy supplier. This paper aims to develop a multi-criteria decision-making model for the evaluation and selection of an IES construction scheme equipped with smart energy management and control platform. Firstly, a comprehensive evaluation criteria system including economy, energy, environment, technology and service is established. The evaluation criteria system is divided into quantitative criteria denoted by interval numbers and qualitative criteria. Secondly, single-valued neutrosophic numbers are adopted to denote the qualitative criteria in the evaluation criteria system. Thirdly, in order to accommodate mixed data types consisting of both interval numbers and single-valued neutrosophic numbers, the TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution) method is extended into a three-stage technique by introducing a fusion coefficient μ. Then, a real case in China is evaluated through applying the proposed method. Furthermore, a comprehensive discussion is made to analyze the evaluation result and verify the reliability and stability of the method. In short, this study provides a useful tool for the energy supplier to evaluate and select a preferred IES construction scheme.

A Non-Normality Measure of the Condition Number for Monitoring and Control

1997 ◽  
Vol 119 (2) ◽  
pp. 217-222 ◽  
Author(s):  
Kunsoo Huh ◽  
Jeffrey L. Stein
Keyword(s):  
Optimal Control ◽  
Condition Number ◽  
Minimization Problem ◽  
Monitoring And Control ◽  
Proper Selection ◽  
Modal Structure ◽  
L2 Norm ◽  
And Control ◽  
Normality Measure ◽  
Selection Of

Because the behavior of the condition number can have highly steep and multi-modal structure, optimal control and monitoring problems based on the condition number cannot be easily solved. In this paper, a minimization problem is formulated for κ2(P), the condition number of an eigensystem (P) of a matrix in terms of the L2 norm. A new non-normality measure is shown to exist that guarantees small values for the condition number. In addition, this measure can be minimized by proper selection of controller and observer gains. Application to the design of well-conditioned controller and observer-based monitors is illustrated.

scholarly journals Didactic Model: Teaching the English Temporal System to Arabic Freshman Learners of English

2017 ◽  
Vol 19 (_sup1) ◽  
pp. 81-97
Author(s):  
Thana Hmidani
Keyword(s):  
Linguistic Competence ◽  
First Year ◽  
Language Awareness ◽  
Intensive English ◽  
First Year Students ◽  
Medical College ◽  
Temporal System ◽  
Post Test ◽  
And Control ◽  
Selection Of

This study took place at a medical college with 57 Arabic first-year students taking an intensive English course. The aim was to address the problems that learners experience when using the English tenses properly. The didactic model was developed and implemented in the study group only (27 students). Pre, mid-, and post-tests were administered to study and control groups at three points in time. The model is a selection of aspects from different methods combined aiming to lead participants to a higher level of linguistic competence in terms of language awareness, reading and writing skills, and vocubulary building. The results indicated statistically significant differences in the post-test between the two groups over time regarding the level of linguistic competence.

scholarly journals Managing Herbicide Resistance: Listening to the Perspectives of Practitioners. Procedures for Conducting Listening Sessions and an Evaluation of the Process

2018 ◽  
Vol 32 (4) ◽  
pp. 489-497 ◽  
Author(s):  
Jill Schroeder ◽  
Michael Barrett ◽  
David R. Shaw ◽  
Amy B. Asmus ◽  
Harold Coble ◽  
...  
Keyword(s):  
Small Group ◽  
Herbicide Resistance ◽  
Planning Process ◽  
Resistance Management ◽  
Time Of Day ◽  
Full Group ◽  
Group Discussions ◽  
Small Group Discussions ◽  
The Subject ◽  
Selection Of

AbstractSeven half-day regional listening sessions were held between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide-resistance management. The objective of the listening sessions was to connect with stakeholders and hear their challenges and recommendations for addressing herbicide resistance. The coordinating team hired Strategic Conservation Solutions, LLC, to facilitate all the sessions. They and the coordinating team used in-person meetings, teleconferences, and email to communicate and coordinate the activities leading up to each regional listening session. The agenda was the same across all sessions and included small-group discussions followed by reporting to the full group for discussion. The planning process was the same across all the sessions, although the selection of venue, time of day, and stakeholder participants differed to accommodate the differences among regions. The listening-session format required a great deal of work and flexibility on the part of the coordinating team and regional coordinators. Overall, the participant evaluations from the sessions were positive, with participants expressing appreciation that they were asked for their thoughts on the subject of herbicide resistance. This paper details the methods and processes used to conduct these regional listening sessions and provides an assessment of the strengths and limitations of those processes.

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