Insecticide may be defined as a substance or mixture of substances intended to kill, repel or otherwise prevent the insects.
Insecticides are the most powerful tools available for use in pest management. They are highly effective, rapid in curative action, adoptable to most situations, flexible in meeting changing agronomic and ecological conditions and economical
Here I would like to inform you in host selection process by the parasitiods.I hope It would increase your understanding on the steps involved n the host selection process.............................
Biochemical and physiological target sites of insecticides on insectNikita Negi
Different insecticide group act on different target site and mechanism of their toxicity lies in differential actions on the target receptors/channels.
To understand the mode of action of insecticides that target the insect nervous system, it is important to have a basic understanding of how the nervous system operates. In insects, the nervous system is composed of a series of highly specialized, interconnected cells, along which travel electrical charges called impulses. A nervous system is essential for the passage of information through the body by means of electrical signals.
Impulses are driven by the movement of electrically charged sodium, potassium and chloride ions into and out of nerve cells. The uninterrupted transmission of impulses along this series of cells is required for a nervous system to function properly. In insects, prolonged or irreversible disruption of a normal-functioning nervous system will result in death.
the topic which contains the basic aspects regarding biological control of pest and also mass production aspects of some biological entomopathogenic agents.and different types of biological agents in management of pest
Here I would like to inform you in host selection process by the parasitiods.I hope It would increase your understanding on the steps involved n the host selection process.............................
Biochemical and physiological target sites of insecticides on insectNikita Negi
Different insecticide group act on different target site and mechanism of their toxicity lies in differential actions on the target receptors/channels.
To understand the mode of action of insecticides that target the insect nervous system, it is important to have a basic understanding of how the nervous system operates. In insects, the nervous system is composed of a series of highly specialized, interconnected cells, along which travel electrical charges called impulses. A nervous system is essential for the passage of information through the body by means of electrical signals.
Impulses are driven by the movement of electrically charged sodium, potassium and chloride ions into and out of nerve cells. The uninterrupted transmission of impulses along this series of cells is required for a nervous system to function properly. In insects, prolonged or irreversible disruption of a normal-functioning nervous system will result in death.
the topic which contains the basic aspects regarding biological control of pest and also mass production aspects of some biological entomopathogenic agents.and different types of biological agents in management of pest
The Sterile Insect Technique, best known by its acronym SIT and also identified as the Sterile Insect Release Method (SIRM), is a biologically-based method for the management of key insect pests of agricultural and medical/veterinary importance. In the FAO glossary, the Sterile Insect Technique is defined as "a method of pest control using area-wide inundative releases of sterile insects to reduce reproduction in a field population of the same species". It is therefore a type of "birth control" in which wild female insects of the pest population do not reproduce when they are inseminated by released, radiation-sterilized males. Sterilization is induced through the effects of irradiation on the reproductive cells of the insects. SIT does not involve the release of insects modified through transgenic (genetic engineering) processes. In this type of autocidal control, sequential releases of the sterilized insects in adequate sterile to wild male overflooding ratio's lead to a reduction in pest population numbers
Insecticides with growth regulating properties (IGR) may adversely affect insects by
regulating or inhibiting specific biochemical pathways or processes essential for insect
growth and development. Some insects exposed to such compounds may die due to abnormal
regulation of hormone-mediated cell or organ development. Other insects may die either from
a prolonged exposure at the developmental stage to other mortality factors (susceptibility to
natural enemies, environmental conditions etc) or from an abnormal termination of a
developmental stage itself. Insect growth regulators may come from a blend of synthetic
chemicals or from other natural sources, such as plants. The chemical composition of
hormones indigenous to insects is now being studied and used as a basis for developing
analogues or mimics against insects. The similarities, however, in certain aspects of
biochemistry among vertebrates and invertebrates may result in the limited development of
IGRs.
Release of large numbers of insectary reared natural enemies with the goal of “augmenting” natural enemy populations or “inundating” pest populations with natural enemies.
The Sterile Insect Technique, best known by its acronym SIT and also identified as the Sterile Insect Release Method (SIRM), is a biologically-based method for the management of key insect pests of agricultural and medical/veterinary importance. In the FAO glossary, the Sterile Insect Technique is defined as "a method of pest control using area-wide inundative releases of sterile insects to reduce reproduction in a field population of the same species". It is therefore a type of "birth control" in which wild female insects of the pest population do not reproduce when they are inseminated by released, radiation-sterilized males. Sterilization is induced through the effects of irradiation on the reproductive cells of the insects. SIT does not involve the release of insects modified through transgenic (genetic engineering) processes. In this type of autocidal control, sequential releases of the sterilized insects in adequate sterile to wild male overflooding ratio's lead to a reduction in pest population numbers
Insecticides with growth regulating properties (IGR) may adversely affect insects by
regulating or inhibiting specific biochemical pathways or processes essential for insect
growth and development. Some insects exposed to such compounds may die due to abnormal
regulation of hormone-mediated cell or organ development. Other insects may die either from
a prolonged exposure at the developmental stage to other mortality factors (susceptibility to
natural enemies, environmental conditions etc) or from an abnormal termination of a
developmental stage itself. Insect growth regulators may come from a blend of synthetic
chemicals or from other natural sources, such as plants. The chemical composition of
hormones indigenous to insects is now being studied and used as a basis for developing
analogues or mimics against insects. The similarities, however, in certain aspects of
biochemistry among vertebrates and invertebrates may result in the limited development of
IGRs.
Release of large numbers of insectary reared natural enemies with the goal of “augmenting” natural enemy populations or “inundating” pest populations with natural enemies.
Botanicals:
Toxicants or chemicals derived from plants parts like leaves, stems,
roots, seeds etc which are used in insect pest and disease control
Ex. Neem products, Nicotine, Ryania, Rotenone and Pyrethrum
A botanical pesticide is a type of bio pesticide formulation made up of
crude plant extracts or purified compound of plant species for
managing pest and diseases.
• Extracted from plants
• Broad spectrum pesticides
• Low environmental persistence
• Low residual value
• Degrade very fast under the sunlight
Advantages:
• Do not leave harmful residues
• Cheaper than chemical
• Safe to user, environment and non target sp.
• Safe for insect enemies – predator, parasitoids
• Prevent resistance and resurgence
Disadvantages:
• Not true pesticides
• Readily degraded by UV rays or sunlight
• Slow speed of action
• High specificity
• Effective period is less – low self life
This ppt is about natural pesticides. and how they are better than synthetics. this lecture is helpful for students of pharmacognosy and agriculture.
synthetic pesticides are need to be replaced with natural substances and natural methods to control like biological control etc.
pests are creating a huge economic loss so its the need of the time to focus on natural pest control methods.
if you like the lecture comment and share
Secondary Metabolism is a term for pathways for small molecule and products of metabolism that are not absolutely required for the survival of the organism.
A secondary metabolite has an important ecological function.
Examples include antibiotics, mycotoxins etc.
MEDICINAL PLANT BIOTECHNOLOGY UNIT 5, MPG, SEM 2 FERMENTATION TECHNOLOGY
Fermentation technology
Application of Fermentation technology
Production of ergot aikaloids
Single cell proteins
Enzymes of pharmaceutical interest.
PLANT SECONDARY METABOLITES IN PLANTS AND THEIR SIGNIFICANCEHemlata
Secondary metabolites attract animals for pollination and seed dispersal.
The plants used in their defence against herbivores and pathogens.
They act as agents of plant-plant competition.
They are used in making drugs, insecticides, flavours, pigments, scents, rubber, spices and other industrial materials like gums, resins for human welfare
NEW ASPECTS OF STEROLS IN PLANT INSECT INTERACTIONHemlata
Sterols are amphipathic lipids based on the steroid ring structure but with a polar hydroxyl (OH group) on one of the 6-membered rings.
They are also known as steroid alcohols, ex. cholesterol.
They are generated in living systems from acetyl-coA by the HMG-CoA reductase pathway.
Physiological mechanisms in regulating insect immunityHemlata
Immunity(derived from Latin term immunis, meaning
exempt),
Immunity refers to reactions by an animal body to foreign substances such as microbes and various macro molecules.
( Abbas et al.,1991)
Immune system- A collection of cells and molecules that protect the body against infection, malignancy and damaged cells. ( Abbas et al., 1991)
Constrains and genetic improvements in baculovirusesHemlata
The baculoviruses form a unique group of arthropod-specific DNA viruses. They have a rod-shaped morphology and replicate in the nucleus of infected cells. Most of these viruses infect insects of the orders Lepidoptera, Hymenoptera and Diptera.
Life tables concept was first formulated by Raymond Pearl (1924)
Life tables is the systematic tabulation of births and deaths of an organism. It is summary statement on the life of a typical individual of population or a cohort of individuals. .
It is an especially useful approach in entomology where developmental stages are discrete and mortality rates may vary widely from one life stage to another.
From a pest management standpoint, it is very useful to know when (and why) a pest population suffers high mortality.
Parasitoid wasps of genus Trichogramma (Hymenoptera: Trichogrammatidae) includes several species that are frequently used as biological control agents worldwide.
Trichogramma spp. are egg parasitoids which lay their eggs inside the eggs of insect pests.
Host of this parasitoid are the eggs of Sugarcane borers, Cut worms (Agrotis spp.), Cotton bollworms and Maize stem borer(Chilo pertellus).
Characterization and the Kinetics of drying at the drying oven and with micro...Open Access Research Paper
The objective of this work is to contribute to valorization de Nephelium lappaceum by the characterization of kinetics of drying of seeds of Nephelium lappaceum. The seeds were dehydrated until a constant mass respectively in a drying oven and a microwawe oven. The temperatures and the powers of drying are respectively: 50, 60 and 70°C and 140, 280 and 420 W. The results show that the curves of drying of seeds of Nephelium lappaceum do not present a phase of constant kinetics. The coefficients of diffusion vary between 2.09.10-8 to 2.98. 10-8m-2/s in the interval of 50°C at 70°C and between 4.83×10-07 at 9.04×10-07 m-8/s for the powers going of 140 W with 420 W the relation between Arrhenius and a value of energy of activation of 16.49 kJ. mol-1 expressed the effect of the temperature on effective diffusivity.
UNDERSTANDING WHAT GREEN WASHING IS!.pdfJulietMogola
Many companies today use green washing to lure the public into thinking they are conserving the environment but in real sense they are doing more harm. There have been such several cases from very big companies here in Kenya and also globally. This ranges from various sectors from manufacturing and goes to consumer products. Educating people on greenwashing will enable people to make better choices based on their analysis and not on what they see on marketing sites.
"Understanding the Carbon Cycle: Processes, Human Impacts, and Strategies for...MMariSelvam4
The carbon cycle is a critical component of Earth's environmental system, governing the movement and transformation of carbon through various reservoirs, including the atmosphere, oceans, soil, and living organisms. This complex cycle involves several key processes such as photosynthesis, respiration, decomposition, and carbon sequestration, each contributing to the regulation of carbon levels on the planet.
Human activities, particularly fossil fuel combustion and deforestation, have significantly altered the natural carbon cycle, leading to increased atmospheric carbon dioxide concentrations and driving climate change. Understanding the intricacies of the carbon cycle is essential for assessing the impacts of these changes and developing effective mitigation strategies.
By studying the carbon cycle, scientists can identify carbon sources and sinks, measure carbon fluxes, and predict future trends. This knowledge is crucial for crafting policies aimed at reducing carbon emissions, enhancing carbon storage, and promoting sustainable practices. The carbon cycle's interplay with climate systems, ecosystems, and human activities underscores its importance in maintaining a stable and healthy planet.
In-depth exploration of the carbon cycle reveals the delicate balance required to sustain life and the urgent need to address anthropogenic influences. Through research, education, and policy, we can work towards restoring equilibrium in the carbon cycle and ensuring a sustainable future for generations to come.
Natural farming @ Dr. Siddhartha S. Jena.pptxsidjena70
A brief about organic farming/ Natural farming/ Zero budget natural farming/ Subash Palekar Natural farming which keeps us and environment safe and healthy. Next gen Agricultural practices of chemical free farming.
Diabetes is a rapidly and serious health problem in Pakistan. This chronic condition is associated with serious long-term complications, including higher risk of heart disease and stroke. Aggressive treatment of hypertension and hyperlipideamia can result in a substantial reduction in cardiovascular events in patients with diabetes 1. Consequently pharmacist-led diabetes cardiovascular risk (DCVR) clinics have been established in both primary and secondary care sites in NHS Lothian during the past five years. An audit of the pharmaceutical care delivery at the clinics was conducted in order to evaluate practice and to standardize the pharmacists’ documentation of outcomes. Pharmaceutical care issues (PCI) and patient details were collected both prospectively and retrospectively from three DCVR clinics. The PCI`s were categorized according to a triangularised system consisting of multiple categories. These were ‘checks’, ‘changes’ (‘change in drug therapy process’ and ‘change in drug therapy’), ‘drug therapy problems’ and ‘quality assurance descriptors’ (‘timer perspective’ and ‘degree of change’). A verified medication assessment tool (MAT) for patients with chronic cardiovascular disease was applied to the patients from one of the clinics. The tool was used to quantify PCI`s and pharmacist actions that were centered on implementing or enforcing clinical guideline standards. A database was developed to be used as an assessment tool and to standardize the documentation of achievement of outcomes. Feedback on the audit of the pharmaceutical care delivery and the database was received from the DCVR clinic pharmacist at a focus group meeting.
Willie Nelson Net Worth: A Journey Through Music, Movies, and Business Venturesgreendigital
Willie Nelson is a name that resonates within the world of music and entertainment. Known for his unique voice, and masterful guitar skills. and an extraordinary career spanning several decades. Nelson has become a legend in the country music scene. But, his influence extends far beyond the realm of music. with ventures in acting, writing, activism, and business. This comprehensive article delves into Willie Nelson net worth. exploring the various facets of his career that have contributed to his large fortune.
Follow us on: Pinterest
Introduction
Willie Nelson net worth is a testament to his enduring influence and success in many fields. Born on April 29, 1933, in Abbott, Texas. Nelson's journey from a humble beginning to becoming one of the most iconic figures in American music is nothing short of inspirational. His net worth, which estimated to be around $25 million as of 2024. reflects a career that is as diverse as it is prolific.
Early Life and Musical Beginnings
Humble Origins
Willie Hugh Nelson was born during the Great Depression. a time of significant economic hardship in the United States. Raised by his grandparents. Nelson found solace and inspiration in music from an early age. His grandmother taught him to play the guitar. setting the stage for what would become an illustrious career.
First Steps in Music
Nelson's initial foray into the music industry was fraught with challenges. He moved to Nashville, Tennessee, to pursue his dreams, but success did not come . Working as a songwriter, Nelson penned hits for other artists. which helped him gain a foothold in the competitive music scene. His songwriting skills contributed to his early earnings. laying the foundation for his net worth.
Rise to Stardom
Breakthrough Albums
The 1970s marked a turning point in Willie Nelson's career. His albums "Shotgun Willie" (1973), "Red Headed Stranger" (1975). and "Stardust" (1978) received critical acclaim and commercial success. These albums not only solidified his position in the country music genre. but also introduced his music to a broader audience. The success of these albums played a crucial role in boosting Willie Nelson net worth.
Iconic Songs
Willie Nelson net worth is also attributed to his extensive catalog of hit songs. Tracks like "Blue Eyes Crying in the Rain," "On the Road Again," and "Always on My Mind" have become timeless classics. These songs have not only earned Nelson large royalties but have also ensured his continued relevance in the music industry.
Acting and Film Career
Hollywood Ventures
In addition to his music career, Willie Nelson has also made a mark in Hollywood. His distinctive personality and on-screen presence have landed him roles in several films and television shows. Notable appearances include roles in "The Electric Horseman" (1979), "Honeysuckle Rose" (1980), and "Barbarosa" (1982). These acting gigs have added a significant amount to Willie Nelson net worth.
Television Appearances
Nelson's char
Artificial Reefs by Kuddle Life Foundation - May 2024punit537210
Situated in Pondicherry, India, Kuddle Life Foundation is a charitable, non-profit and non-governmental organization (NGO) dedicated to improving the living standards of coastal communities and simultaneously placing a strong emphasis on the protection of marine ecosystems.
One of the key areas we work in is Artificial Reefs. This presentation captures our journey so far and our learnings. We hope you get as excited about marine conservation and artificial reefs as we are.
Please visit our website: https://kuddlelife.org
Our Instagram channel:
@kuddlelifefoundation
Our Linkedin Page:
https://www.linkedin.com/company/kuddlelifefoundation/
and write to us if you have any questions:
info@kuddlelife.org
2. What are
Insects???
• Insects are tracheate arthropods
whose body is divided into three
regions namely head, thorax and
abdomen possessing two pairs
of wings and three pairs of legs
in thoracic region, genital
organs towards posterior end of
the body and with decentralized
nervous system.
• According to Imm’s
3. INSECTS
• Many insects are considered pests by humans.
• One-sixth of all crops grown worldwide are lost due
to herbivorous insects and the plant diseases they
transmit.
• Insects are responsible for damage to growing crops.
4. INSECTICIDES
• Insecticide may be defined as a
substance or mixture of substances
intended to kill, repel or otherwise
prevent the insects.
• Insecticides are the most powerful
tools available for use in pest
management.
• They are highly effective, rapid in
curative action, adoptable to most
situations, flexible in meeting
changing agronomic and ecological
conditions and economical.
5. • Most of the insecticides commonly used by Pest
Management Professionals can be technically classified
as neurotoxins — i.e., their target site within the target
organism is some aspect of the nervous system.
• The commonly used insecticides, such as insect growth
regulators (juvenile hormone analogs and chitin
synthesis inhibitors) and a few miscellaneous active
ingredients (borates, energy inhibitors and dehydrating
dusts), do not target the nervous system.
6. BIOCHEMICAL TARGET SITE
• Insecticides that do not target the nervous system also
can be subdivided by target site and mode of action, and
include:
1. Muscular calcium channel disruptors
2. Insect growth regulators.
3. Inhibitors of energy production and non-specific
cellular disruptors.
4. Insecticides that act via desiccation (exoskeleton).
7. BIOCHEMICAL TARGET SITE OF
INSECTICIDES
Chemical Group MOA Target Site Route of Entry
Diamides Muscle Stimulation Muscular Calcium channel Oral
Juvenile Hormone Analogs Mimic Juvenile
Hormone Action
JH Degradative Enzymes/
Receptor
Contact & oral
Chitin Synthesis
Inhibitors
Block Chitin
Formation
Exoskeleton Oral
Amidinohydrazones Inhibit Energy production Mitochondria within cells Oral
Pyrroles Inhibit Energy production Mitochondria within cells Contact
Fumigant (sulfuryl
fluoride)
Inhibit Energy
Production
Citric Acid / Glycolysis
Cycles in Cells
Inhalation
Borates Non‐Specific
Metabolic Disruption
Cells Oral
Dehydrating dust Adsorption of
Cuticular Wax Layer
Exoskeleton Contact
8. I.Muscular Calcium Channel toxins
•This includes the active ingredient
chlorantraniliprole.
• It is being developed world-wide
by DuPont belonging to a new class of selective
insecticides featuring a novel mode of action.
• It control a range of pests belonging to the
order Lepidoptera and
someother Coleoptera, Diptera and Isoptera species.
9. Mode of action
• They act on muscular calcium
channels that are under direct
control of the nervous system.
• Diamides bind and stimulate
muscular calcium channels,
causing uncontrolled calcium
release and resultant muscle
contractions.
• Early stages insects appear as
rigid or "contractile" paralysis.
10. II.Insect Growth Regulators
• Insect growth regulators (IGRs) used by the pest management
industry include the juvenile hormone analogs and the chitin synthesis
inhibitors.
• IGRs do not act on the nervous system.
• They disrupt critical physiological functions associated with normal
insect growth, development and reproduction (egg production).
• IGR-containing products generally have low mammalian toxicity (i.e.,
large LD50 values).
• IGRs must be handled safely and applied with a great deal of care and
consideration for non-target organisms.
11. • JHAs may bind to juvenile hormone-degrading enzymes, the juvenile
hormone receptor itself or a combination of both factors.
• The high levels of juvenile hormone within the insect body at a time when it
should not naturally be present.
• This consequences on insect survival and reproduction, severely disrupting
the insect's development and/or altering its reproductive physiology.
• Death or sterilization often results from exposure to JHAs. For example, fire
ant queens exposed to JHA-based baits stop producing eggs and/or colonies
experience a shift in caste composition.
Chemical Class: Juvenile Hormone
Analogs
12. Chemical Class: Chitin Synthesis
Inhibitors
• Chitin synthesis inhibitors do not act on the insect's nervous
system.
• They disrupt an important biochemical pathway responsible for the
synthesis of chitin.
• CSIs used by the structural pest management industry include
diflubenzuron for termite control, and hexaflumuron and
noviflumuron for the control of termites.
• Termite baits that contain chitin synthesis inhibiting insecticides
block chitin formation in molting termites exposed to the active
ingredient.
13. Lufenuron
• Lufenuron is a chitin synthesis inhibitor
used for flea control.
• It is delivered orally and absorbed directly
into the animal's bloodstream.
• These fleas are obligate blood feeders
,consumption of lufenuron results in the
production of eggs that fail to hatch ,since
insect eggs contain chitin, flea larvae are
also killed by lufenuron.
14. Figure. If this food source contains the chitin synthesis inhibitor
lufenuron, then larval fleas cannot properly molt and die when
they molt.Adult female fleas that have fed on lufenuron-
impregnated host blood do not produce viable eggs, but are
themselves unaffected.
15. Buprofezin
• It is a chitin synthesis inhibitor which acts
specifically on sucking pests such as plant hoppers
and whiteflies.
• Its mode of action resembles that of benzoylphenyl
ureas, although its structure is not analogous.
• The compound inhibits incorporation of 3H-
glucose and N-acetyl-D-3H-glucosamine into
chitin .
• The characteristic symptoms in the greenhouse
whitefly result of chitin deficiency, the procuticle
of the whitefly nymphs loses its elasticity and the
insect is unable to molt.
16. Mode of action of CSI’s
• The chitin synthesis inhibitors block an
important enzyme, called chitin synthase.
• This enzyme is directly responsible for
the conversion of certain chemicals into
chitin.
• In the absence of this enzyme, chitin
cannot be synthesized.
• The prevention of chitin synthesis is fatal
for the affected insect.
17. III. Inhibitors of Energy Production and
Non-Specific Cellular Disruptors
• This includes the active ingredient hydramethylnon.
Hydramethylnon is a cellular poison.
• It prevents the mitochondria within cells to produce
energy for the cell and the organism to conduct its
normal activities.
Chemical Class: Amidinohydrazone
18. • Insects exposed to hydramethylnon die slowly as energy
is depleted and not restored.
• The affected insects essentially are depleted of the
energy needed to sustain normal body functions,
causing them to die.
• Insects poisoned by hydramethylnon, as well as the
diamide insecticide chlorantraniloprole, display limp
paralysis much as the inhibitory neurotoxins.
Mode of action
19. Chemical Class: Pyrrole
• This includes the active ingredient chlorfenapyr.
• Indoxacarb, clorfenapyr must be converted by enzymes
within the insect to an active form by a process known
as activation.
• Chlorfenapyr is converted to a new molecule that is
insecticidal.
• These metabolite is toxic to mammals which lack the
necessary enzymes to make the conversion from
inactive to active insecticide.
20. • The mode of action of chlorfenapyr's active metabolite is much like
that of hydramethylnon, i.e., it destroys the mitochondria's ability
to supply energy to meet the insect's needs.
Mode of action
21. Chemical Class: Structural Fumigants
• This includes the active ingredient sulfuryl fluoride.
• In the structural pest control industry, sulfuryl
fluoride is used to fumigate residential and
commercial buildings.
22. Mode of action
• Sulfuryl fluoride inhibits energy production in cells
but does not appear to have a specific target site.
• It is a non-specific metabolic inhibitor that causes a
deprivation of cellular energy.
• Fumigants can be hazardous to applicators and non-
target organisms if mishandled or misapplied.
• A small amount of the warning agent chloropicrin
(tear gas) is applied in residential and commercial
buildings prior to the introduction of sulfuryl
fluoride gas.
23. Chemical Class: Borates
• This includes the active ingredients borax, boric acid
and disodium octaborate tetrahydrate.
• Boron-based active ingredients are exclusively oral
toxicants — they neither exhibit contact toxicity nor
act as cuticular desiccants.
• Borates must either be consumed in baits or
groomed off the insect's body after having been
picked up as a dust formulation.
24. • They are general cellular toxins or non-specific
metabolic disruptors (perhaps even mitochondrial
disruptors).
• These is a feeding deterrent to some pests at high
concentrations, boric acid exhibits excellent water
solubility and is slow acting at low concentrations.
• Disodium octaborate tetrahydrate is an active
ingredient in preventive wood treatments targeted at
both wood-destroying insects and fungi.
Mode of action
25. IV. Insecticides that Act Via Desiccation
• This includes the active ingredients silica gels and diatomaceous
earth.
• Silica gels are synthetically produced, while diatomaceous earth
is the fossilized, skeletal remains of minute microorganisms
known as diatoms.
• Diatoms are unearthed, mined, and used for insect control,
among a myriad of other uses.
• Both silica gels and diatomaceous earth adsorb the thin wax
layer on insect exoskeleton.
Chemical Class: Dehydrating Dusts
26. • The wax layer normally prevents insects from losing
water through their exoskeleton and desiccating.
• By adsorbing the wax layer, silica gels and
diatomaceous earth increase the permeability of the
exoskeleton, resulting in insect death by dehydration.
• Silica gels and diatomaceous earth are most effective
against crawling insects in dry environments where free
water is limited.
Mode of action
27. • The target site of the insect nervous system can be
subdivided based on their specific target site within
the nervous system.
• Specific neurological target sites include sodium and
chloride channels and various components of the
acetylcholine system.
PHYSIOLOGICAL TARGET SITE
28. PHYSIOLOGICAL TARGET SITE OF
INSECTICIDE
Chemical Group MOA Target Site Route of Entry
Pyrethrins /
Pyrethroids
Sodium Channel
Modulation
Axon of nerve Contact
Oxadiazines Sodium Channel blockage Axon of nerve Oral
Semicarbazones Sodium Channel blockage Axon of nerve Oral
OPs / Carbamates Acetyl cholinesterase
inhibition
Nerve Synapse Contact
Neonicotinoids Acetylcholine Receptor
stimulation
Nerve Post‐synapse Contact & Oral
Spinosyns Acetylcholine Receptor
stimulation
Nerve Post‐synapse Oral
Phenylpyrazoles GABA Receptor blockage Nerve Post‐synapse Contact & Oral
Avermectins Glutamate Receptor
stimulation
Nerve Post‐synapse Oral
29. I.Neurological Target Site: Sodium
Channels
• This includes the active ingredients pyrethrins, bifenthrin,
permethrin, cyfluthrin, beta-cyfluthrin, deltamethrin,
cypermethrin, and
lambda-cyhalothrin.
Chemical Class: Pyrethrins and Pyrethroids
30. • Both pyrethrins and pyrethroids disrupt normal nerve function in a
region of the nerve cell known as the axon.
• They inhibit the on/off switch of nerve cells, called sodium
channels, by delaying the rate at which they close, or turn off.
• This results in uncontrolled, uninterrupted nerve firing seen as a
convulsing insect (tremors and shaking) that quickly dies.
• Pyrethroids are toxic to many Hymenoptera (ants, bees and wasps).
• They are easily hydrolyzed (broken down in the presence of
moisture) and are, thus, not very persistent.
Mode of action
31. Chemical Class: Oxadiazines
• This includes the active
ingredient indoxacarb.
Mode of action
• When indoxacarb enters the insect, it is broken down into a new molecule with
insecticidal properties. This process, mediated by enzymes within the insect, is
referred to as activation.
• After activation, the newly formed molecule (called a metabolite) targets sodium
channels along the nerve axon
• The active metabolite tightly binds to the sodium channel, and completely blocks
sodium ion flow into nerve cells.
• Those insects poisoned with indoxacarb appear paralyzed and limp, and are
incapable of movement.
32. Chemical Class: Semicarbazones
• The semicarbazones are a very
new insecticide class.
• This includes the active
ingredient metaflumizone.
• Early indications are that metaflumizone acts similar to the
indoxacarb metabolite.
• It blocks sodium channels and prevents sodium ion
movement into nerve cells.
• The result of this blockage is a loss of neurological function
that is similar to that described for indoxacarb.
Mode of action
33. II. Neurological Target Site:
Acetylcholine System
• These are produced by the process of
esterification between phosphoric acid
and alcohol.
• They undergo hydrolysis with the
liberation of alcohol from the esteric
bond.
• OPs are the main components of nerve gas.
• Eg; dichlorvos chlorpyrifos (Dursban), dichlorvos (DDVP),
malathion, diazinon, acephate (Orthene), propetamphos
(Safrotin) and naled (Dibrom for mosquitoes). etc.
Chemical Class: Organophosphates (OPs)
34. • A carbamate is an organic compound
derived from carbamic acid.
• A carbamate group, carbamate ester,
and carbamic acids are functional groups
that are inter-related structurally and often are interconverted chemically.
• The carbamates are synthetic insecticides modeled after a natural plant toxin (called
physostigmine) from the Calabar bean.
• It cause carbamylation of acetylcholine esterase (AChE) at the level of neuronal
synapses. Their binding to AChE is reversible, and the duration of action is about 24
hours.
• Eg; Carbofuran, aldicarb carbaryl (Sevin), bendiocarb (Ficam), and propoxur
(Baygon). etc.
Chemical Class: Carbamates
35. • OPs and carbamates act by inhibiting the acetylcholinesterase (AchE) enzyme in
the nervous system.
• AchE performs a critical job in the nervous system by removing the neurotransmitter
acetylcholine (Ach) from its receptor on the post-synapse nerve.
• AchE prevents overstimulation of the nervous system because it removes Ach.
without AchE, a stimulated nerve cannot return to its resting state.
• OPs and carbamates tie-up (inhibit) AchE, preventing it from removing Ach from its
receptor site.
• The result is overstimulation of the nerve cell, and death of the insect.
Mode of action
36.
37. Chemical Class: Neonicotinoids
• Neonicotinoids are a new class
of insecticides chemically related
to nicotine.
• The name literally means “new nicotine-like insecticides”.
• The neonicotinoids act on certain kinds of receptors in the nerve synapse.
• They are much more toxic to invertebrates, like insects, than they are to
mammals, birds and other higher organisms.
• Neonicotinoids are synthetic materials modeled after the natural, plant-
produced insecticide nicotine.
• Eg: Imidacloprid, dinotefuran, thiamethoxam, clothianidin and acetamiprid.
38. • Neonicotinoids target the insect nervous system by binding to the
acetylcholine (Ach; a neurotransmitter) receptor on the post-synapse
nerve cell.
• Ach binds to this receptor for only milliseconds (1/1,000 of a second)
at a time, resulting in short and controlled nerve stimulation.
• The neonicotinoids bind to the Ach receptor for very long periods,
approximately minutes or greater.
• This in nerve hyper-stimulation.
• Insects exposed to a neonicotinoid insecticide exhibit symptoms of
tremors and hyperactivity, much like pyrethrins, pyrethroids and
fipronil.
Mode of action
39. Chemical Class: Spinosyns
• This includes the active ingredient
spinosad.
• Spinosyns (also known as
"Naturalytes") are chemicals produced by the soil
bacterium Saccharopolyspora spinosa.
• Spinosyns are acquired by fermentation of S. spinosa
cultures, then by purification and modification of the
active chemical components produced by the microbe.
40. • They primarily targeting binding sites
on nicotinic acetylcholine receptors
(nAChRs) of the insect nervous
system.
• Spinosoid binding leads to disruption
of acetylcholine neurotransmission.
• Spinosad also has secondary effects
as a γ-amino-butyric acid (GABA).
• It kills insects by hyperexcitation.
.
Mode of action
• Spinosyn A
• Spinosyn A initially caused
involuntary muscle contractions
and tremors by widespread
excitation of neurons in the
central nervous system.
• Spinosyn A had no direct
neuromuscular depressant effect
and at very high concentrations
actually enhanced neuromuscular
transmission.
• Spinosyn D
• Spinosoid is a minor component
of spinosad, It acts as an agonist
of insect nicotinic
acetylcholinesterase receptors.
41. III. Neurological Target Site: Chloride
Channels
• Phenylpyrazole insecticides are a class of
chemically-related broad-spectrum insecticides.
Chemical Class: Phenylpyrazole
42. • Fipronil acts on the insect nervous system by binding to and
blocking the GABA receptor on the post-synapse nerve cell.
• This blockage prevents GABA from binding to the receptor
site, which then prevents the influx of chloride ions into the
post-synapse nerve cell.
• These chloride ions limit and balance the electrical activity
within nerve cells, blocking chloride influx leads to rapid,
uncontrolled nerve firing throughout the nervous system.
• Fipronil-treated insects exhibit tremors and shaking.
Mode of action
43. Chemical Class: Avermectins
• This includes the active ingredients
abamectin, emamectin benzoate
and ivermectin.
• The avermectins were originally
isolated from soil bacteria from the genus Streptomyces.
• Older avermectins, such as abamectin, are used in their natural
form; however, newer materials, such as emamectin benzoate,
are partially natural and synthetic. Ivermectin is another
natural avermectin.
• It has uses for endoparasite control in pets and companion
animals.
44.
45. • They bind the chloride channels that are regulated by the
neurotransmitter glutamate.
• While phenylpyrazoles block chloride channels, the
avermectins stimulate them, resulting in constant and
unimpeded chloride ion flow into nerve cells.
• This results in complete inactivation of nerve cells and a loss
of neurological function.
• Poisoning symptoms in insects are similar to those caused by
indoxacarb and metaflumizone (limp paralysis).
Mode of action