Questions related to Insecticide Resistance
So, i've added 2uL of chlorpyrifos in my culture of RT-Gill cells that were in L15 medium. The first thing that concerned me, was that it inmediatly reacted forming some tiny bubbles, like when you open a bottle of soda. Also, the color of the medium changed from colorless to redish. (See the first photo, "T" are the ones with chlorpyrifos, and "C" my control). I inmediatly thought that my cells died, but they looked fine (i think) when i saw them under a microscope. 48Hrs later, i came back to see the medium and do a protein extraction, so i took the medium but ones with chlorpyrifos left a jelly thing in the bottom (like solidified silicone), and took a bit by scraping it (see the last photo).
I honestly have no idea what caused this reaction.
I have no experience but interested to learn and apply mathematical models for insecticide resistance. It would be great if some colleague guide me from where to start. I have experience for insecticide resistance monitoring, isolines comparison, fitness cost analysis and genetics of resistance in some Lepidoptera insect pests like Spodoptera litura, Helicoverpa armigera.
Many thanks in advance
What could be possible reasons for insecticide resistance among insects from areas which have very little exposure of insecticides or there is no selection pressure and the areas are rich in biodiversity.
I need some guidance or clarifications on how to calculate the effects of the combinations of insecticides when you have the adult mortality rate of individual products and of their mixture.Example: Product A: 78%; B: 50% C: 65% and their mixture 89%.
When I looked in Insecticide Resistance Monitoring, Mechanisms and Management Manual I was confused with their calculations. Best regards
Thanks in advance
Insecticides are becoming resistant over the period, global warming knocking the door of more people being exposed to Dengue, Chikungunya and Zika virus (and other Vector-borne diseases (VBD)) across the world. Controlling mosquitoes in alternative techniques is a timely demand. Wolbachia had shown remarkable success (although in only few countries so far) for controlling dengue virus. If the technology can be used for other Aedes-borne diseases (Chikunguny, Zika) this will be a remarkable step for controling VBDs.
Any update in this area?
Hi all. During a survey I obtained five individuals of Aedes aegypti in an immature stages only in one locality, so I must start a colony of this place until I get enough larvae and adults for test procedures for resistance . Could I start a colony with a low genetic variability considering that I will do resistance tests in F1, F2, ......?
I can´t find articles that compare colonies with few and several mosquitoes in the same locality. I hope you can suggest articles or experiences. Thanks
Hi everyone, I am trying to find related insecticide resistance genes in a new organism. I am selecting the cds of these genes and running a tBLASTx against my de novo assembled genome. But, today I had a doubt, do I have to select those genes from the closest model specie? Or can I select the gene predicted in the closest specie? Even if this is not a model organism.
The thing is that I want to be the most sure possible when I find those genes in my genone, and, maybe, running a BLAST with predicted genes is not the best idea.
Any suggestion is welcome!
Hi everyone! I am new here.
We have de novo assembled a genome and I would like to know which genes are related to insecticide resistance. I am looking for the sequences of those genes of related species in NCBI, then I extract the cds and blast it with my transcripts. As we have also assembled the transcriptome, we have transcripts sequences too. So I do a tBLASTx search of my genes of interest vs my transcripts and find those transcripts related to insecticide resistance. This way, I can find the position of these transcripts in the genome. But, in order to sequence those genes, how can I design a PCR to amplify only one of these genes? Should I just pick the genomic sequence of one of the exons? or should I carry out a RT-PCR with the transcript sequence?
Any advice is welcome! Thanks!
Insect pest problems and their management is a part of modern agriculture. Pest control measures, specially the use of chemical pesticides, however, have evoked a lot of controversy and debate vis-a-vis their deleterious effects on the environment and human health in recent times. Chemical control of insects has been used for a long time, but has serious drawback. No doubt they are providing hopeful results in eradication of insect pests and diseases but they are also killing natural enemies present in soil and with crop.
To overcome these problems identification of safe molecules with better insecticidal properties having lower mammalian toxicity, safe to natural enemies etc., which fits well in the IPM concept are needed at present. Due to gradual withdrawal of synthetic insecticides, concern about the environment, increased organic production and development of insecticide resistance, alternative control methods are needed
we have a big problem in pistachio trees, it`s a Agonoscena pistaciae Burkhardt and Lauterer (Hem.: Aphalaridae).
A. pistachiae is resistance to most of insecticide especially Neonicotinoids family.
We should increase resistance of plant.
What should we do?
A new study has tried to assess the genetic variants among mosquitoes that make them more susceptible to spreading deadly viral diseases such as dengue, yellow fever, Zika and chikungunya and more resistant to insecticides that are used to kill them.
Hello, I'm planning to assess insecticide resistance of aphid and its parasitoid along with selection. There are many assays I've found in articles so far.
There are leaf dipping assay, feeding insecticide mixed with 10% sugar solution, bial assay(using residue after drying liquid in a bial).
These are the methods using insecticide directly to adult parasitoid.
And some suggested that using insecticide to the infected aphid(developing parasitoid larvae) is better.
I can't decide which method is more appropriate, but I think that contacting insecticide to adult female only make a selection slower.
I have a question about investigating insecticide ( Neonicoitnoids) resistance mechanism. We have populations of insects that are resistant and susceptible to insecticide, and we are interested to find out about the mechanism behind it. Any recommendation that how we can do it?
Looking forward to hearing your ideas.
I am doing biochemical assays for insecticide resistance in Aedes aegypti populations, micoplate assays, but I am not clear how to calculate the enzyme activity for each assay. I was wondering if I could get in touch with someone who could guide me, since is the first time I do it. Thank you very much.
I have a question for designing the experiment, I am interested to design markers for insecticide resistance in an insect that its genome has not been sequenced. I am thinking to sequence the genome, do de novo assembly and then look for variants between tolerant and control insect. Is this sounds practical? How about going through transcriptomics instead?
Appreciate your comments, Mahnaz
I would like to request researchgate people to comment on the following abstract. Does this report any findings, or convey a message? What are the weakness of this abstract?
Improved design of a synthetic Bt gene stack and testing its insecticidal efficacy in the model plant Arabidopsis
Bacillus thuringiensis (Bt) insecticidal toxin protein encoded by Cry gene is a widely used technology to control insect pest in the crop field. However, development of insect resistant to Cry genes has appeared as a major threat to the durability of this approach, and thus urgent action is required to overcome this problem. Out of many available approaches, stacking of multiple Cry genes in the same plant is thought as the best strategy to delay the development of insect resistant to Cry genes. Here we report the insecticidal activity of a genetically engineered Bt gene stack consisting of Cry1B/Cry1C genes in the model plant Arabidopsis. Cry1B/Cry1C genes were designed to produce a novel version which is free of IP. Components which have the freedom to operate were used to test the insecticidal activity of the modified Cry1B/Cry1C gene stack. Availability of technology that does not require licensing agreement to use, is one of the main barrier to develop GM crops by public sector organizations in the developing countries. Thus, it is expected that the modified Cry1B/Cry1C gene stack will be a valuable tool to develop GM crops for public or humanitarian use in the developing nations.
I´m rearing Anopheles and Aedes mosquitoes for insecticide resistance research. I´m looking for a simple fast method of measuring mosquito quality. I don´t think it´s the same exposing a small underfed mosquito than a big healthy one to the dose of insecticide. I´ve been looking around but wing morphometry is too tedious as I would have to analyse about 300-500 mosquitoes a month... I appreciate any ideas.
Leaf reddening is the cause of stress (biotic, abiotic) indication in sensitive short duration Bt hybrids. Irrigation, Deep vertisols, Stay green Bt hybrid/Bio-stimulants, Long duration hybrids, sucking pest suceeptablitywith insecticides / resistant hybrids and the last WSF against deficit nutrition of P,K, Mg are the causes and found remedies. Stay green colour offered by genotypes, GA3, 6 BA and Strobins and Monocrotophos conjoint additives also.
Glass is inert, can be cleaned with solvents and heat, so it can be reused. But plastic petri-dishes, vials, centrifuge tubes are omnipresent in laboratories, are disposable and can easily be modified. Of course one cannot use an aceton solution on polystyrene dishes or vials, but what are the disadvantages of coating plastic surfaces with insecticides for single use?
I aim to detect the molecular level mechanisms in imparting insecticide resistance in S.litura. Biochemical analysis proved the role of esterase mediated resistance. Which primers/ technique for detecting nucleotide polymorphism (RAPD/ SSR) do you recommend?
Is there any defined criterion for discriminating resistance as Low Moderate or High in P. xyllostella (Based on LC 50 or resistance folds over sus)?
My aim is to look for expression level of insecticide resistance gene. I am working with field collected mosquitoes. How long does the RNA remains stable after the mosquito dies
I have made an insecticide efficiency experiment in the field with white grubs. I have negative values after calculation with Henderson Tilton formula, because population in the control unit was less than treatment. I want to make One Way Anova. But data set does not have normal distribution and I want to transform my data. What kind of transformation should I apply? As I know we use arcsine transformation for percentage data. However as I said before I have negative values and I don't know how to make arcsine transformation to the negative values.
I am doing some experiment with mosquito larvae and pupa for insecticide resistance. In my work I have to do sds page analysis of these mosquito immatures using whole body lysate. Can anybody suggest me the efficient method of sample preparation (grinding and cell lysis) with complete protocol?
Most of the populations showed polygenic (more than one gene) resistance in laboratory selected strains of insect pests..
Is there any correlation present in the economic threshold level and insecticide resistance in insects. As fluctuations in ETL cause variations in insecticides resistance levels must then change in insects?
How can we determine the insecticide resistance gene frequency in stored product pest populations? Especially on Sitophilus species. Can we use Hardy-Weinberg equilibrium?
In order to develop biological control against cixiidae, I'm searching what kind of plant extract could be used as a repellent and/or insecticide.
The literature regarding Xenopsylla cheopis (rat flea) insecticide resistance mechanisms is very scarce. So, if anyone work on this topic, or have some documents, it would be a great help.
Ex: Mirid bugs,leafhoppers. Spidermites.Aphids. Flowerbud maggots etc
We want to investigate insecticide resistance levels in Phlebotomus sandflies from Syria and would like to pursue the genotypic route if possible because phenotypic work is not feasible in the war zone.
There is a growing body of litterature regarding the use of Machine Learning Techniques to build a classifier. How can one come up with such a classifier in order to build a contry-wide prediction model of insecticide resistance in malaria vectors?
In the context of Bt crops literature, Resistance is defined as a heritable trait conferring a pest the hability to overcome the control by the Bt crop. Several authors agree in that "insecticide resistance be defined as an individual trait, which is an inher- ited ability of an insect to tolerate doses of a toxicant that would prove lethal to the majority of individuals in the normal population of the species". Here there seems to be an equivalency of both terms, resistance and tolerance. Part of the literature suggests that resistance involves change in the proportion of susceptibles in the population, while tolerance should be reserved to the status of the population prior to exposure to the Bt crop. Crava et al (2013) state that "We used the term tolerance in the sense defined by Finney
(1971), to refer to a quantitative measure of resistance that is normally distributed among individuals within a population". Other literature use both terms interchangably. Any suggestions about finding clear definitions of these terms?
Yellow Rice Stem Borer (Scirpophaga incertulas) is a major insect pest in Indonesia, especially in Java Island. In several places, there is a population which has been resistant to insectide. We need to start a study on its behaviour and life cycle. Perhaps by rearing this insect in greenhouse condition with rice (Oryza sativa) as its natural diet, all of the informations will be provided. I would be thankful if anyone can help me by sharing any information about the method in rearing this insect.
I am doing some experiments on the detection of biochemical mechanisms of insecticide resistance in mosquito larva. Due to some problem I am interested in preserving these larvae for 2-3 months so that later on these experiments may be continued.
By the application of pyrethroids, you can enhance the resistance to neonicotinoids or vice versa. I read some information about how they can affect the same site of action, but I want more literature to be sure about this.
I am designing a PCR based assay to genotype an SNP within the kdr gene that is associated with insecticide resistance. I would like to validate the assay using DNA from individuals know to have the resistance allele (or at least to have the suspected allele). I'm looking for frozen/preserved individual mosquitoes and/or mosquito eggs that could be used to establish my own colony.
I am working to identify the mechanism of insecticides resistance in sucking insect pests by using synergists and measuring enzymes level
I know how to calculate the selectivity toxicity ratio under laboratory condition but I don't know under what field condition.
I would like to discuss the best methods of exposure used to select resistant populations in lab conditions, such as excised leaves (up taking the solution), artificial membrane, dipping technique, or even direct exposure via vial bioassays. I know there is a lot of material covering this on the internet but I would like to hear your personal opinion and experience.