Insecticide
An insecticide is a substance used to kill insects. They
include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are
used in agriculture, medicine, industry and by consumers. Insecticides are claimed to be a major
factor behind the increase in agricultural 20th century\'s productivity . Nearly all insecticides
have the potential to significantly alter ecosystems; many are toxic to humans; some concentrate
along the food chain.
Insecticides can be classified in two major groups: systemic insecticides, which have residual or
long term activity; and contact insecticides, which have no residual activity.
Furthermore, one can distinguish three types of insecticide. 1. Natural insecticides, such as
nicotine, pyrethrum and neem extracts, made by plants as defenses against insects. 2. Inorganic
insecticides, which are metals. 3. Organic insecticides, which are organic chemical compounds,
mostly working by contact.
The mode of action describes how the pesticide kills or inactivates a pest. It provides another
way of classifying insecticides. Mode of action is important in understanding whether an
insecticide will be toxic to unrelated species, such as fish, birds and mammals.
Insecticides are distinct from insect repellents, which do not kill.
activity
Systemic insecticides become incorporated and distributed systemically throughout the whole
plant. When insects feed on the plant, they ingest the insecticide. Systemic insecticides produced
by transgenic plants are called plant-incorporated protectants (PIPs). For instance, a gene that
codes for a specific Bacillus thuringiensis biocidal protein was introduced into corn and other
species. The plant manufactures the protein, which kills the insect when consumed .Contact
insecticides are toxic to insects upon direct contact. These can be inorganic insecticides, which
are metals and include arsenates, copper and fluorine compounds, which are less commonly
used, and the commonly used sulfur. Contact insecticides can be organic insecticides, i.e. organic
chemical compounds, synthetically produced, and comprising the largest numbers of pesticides
used today. Or they can be natural compounds like pyrethrum, neem oil etc. Contact insecticides
usually have no residual activity.
Efficacy can be related to the quality of pesticide application, with small droplets, such as
aerosols often improving performance.[4][better source needed]
Biological pesticides
Main article: Biopesticide
Many organic compounds are produced by plants for the purpose of defending the host plant
from predation. A trivial case is tree rosin, which is a natural insecticide. Specific, the production
of oleoresin by conifer species is a component of the defense response against insect attack and
fungal pathogen infection . Many fragrances, e.g. oil of wintergreen, are in fact antifeedants.
Four extracts of plants are in commercial use: pyrethrum, rotenone, neem oil, and various
essential oil.
MICROBIAL INSECTIDES...USES AND APPLICATIONS OF INSECTICIDESlokismicrobiology
Microbial insecticides are those microorganisms or their products that are capable of attacking and killing pest insects. This may be considered to be an aspect of biological control, but when one is dealing with the products of such microbes the control may be termed chemical.
MICROBIAL INSECTIDES...USES AND APPLICATIONS OF INSECTICIDESlokismicrobiology
Microbial insecticides are those microorganisms or their products that are capable of attacking and killing pest insects. This may be considered to be an aspect of biological control, but when one is dealing with the products of such microbes the control may be termed chemical.
Recent Advances in Biopesticides BY Ghulam Murtazamurtaza8513
Biopestides are being manufactured all across the world but due to limited resources the research in biopesticides is not upto the mark. however advancement has been made in recent decades to protect crops from the attack of different insect pest in order to meet the agricultural productivity.
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
PLANT PROTECTION:BIOLOGICAL,PHYSICAL AND MECHANICAL,CHEMICAL,BIOPESTICIDE
Biological pest control is the method of pest control using the natural enemies of pests, such as their parasites, pathogens and predators. In this method, the natural enemies are multiplied and released to the field by artificial means to fight the pests. Biological control method involves three main steps, namely inoculation, augmentation and conservation.
Mechanical controlThis is the procedure in which members of the pest species are trapped or killed by mechanical means, or are prevented from gaining access to the host plants by making barriers. Mechanical pest control has only limited application, though it is effective under certain circumstances. It is very effective in the initial stage of infestation of some insect pests, such as aphids, jassids, scale insects, etc. It can give spectacular results, if carried out as an organized campaign over a larger area.
Physical controlThis involves the deliberate modification of some physical factors to slow down the growth of pest population or to minimise or prevent pest infestation
Biopesticides are the organic pesticides obtained or prepared from living organisms. They are harmless to beneficial plants, but control the growth of harmful pests.
This PPT describes about the
What is pesticides?
Uses of pesticides.
Manufacturing Process.
Classification of pesticides.
Prevention of Pesticides.
Benefits of pesticides.
Eco-pesticides.
Agricultural inputs, list of agricultural inputs and Insecticide used in Bang...MD. ZANE ALAM
Agricultural inputs are defined as products permitted for use in organic farming. These include feedstuffs, fertilizers and permitted plant protection products as well as cleaning agents and additives used in food production.
Weighted average cost of all financing sources(Thus weight is give.pdfanilgoelslg
Weighted average cost of all financing sources
(Thus weight is given to all the sources of finance)
Solution
Weighted average cost of all financing sources
(Thus weight is given to all the sources of finance).
( 1) jirovecii tropozoites produce sexually by fission is a false st.pdfanilgoelslg
( 1) jirovecii tropozoites produce sexually by fission is a false statement.
(2) influenza,mycoplasma,rhinovirus,respiratory syncytial virus are responsible for respiratory
disease in infants.
Solution
( 1) jirovecii tropozoites produce sexually by fission is a false statement.
(2) influenza,mycoplasma,rhinovirus,respiratory syncytial virus are responsible for respiratory
disease in infants..
Recent Advances in Biopesticides BY Ghulam Murtazamurtaza8513
Biopestides are being manufactured all across the world but due to limited resources the research in biopesticides is not upto the mark. however advancement has been made in recent decades to protect crops from the attack of different insect pest in order to meet the agricultural productivity.
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
PLANT PROTECTION:BIOLOGICAL,PHYSICAL AND MECHANICAL,CHEMICAL,BIOPESTICIDE
Biological pest control is the method of pest control using the natural enemies of pests, such as their parasites, pathogens and predators. In this method, the natural enemies are multiplied and released to the field by artificial means to fight the pests. Biological control method involves three main steps, namely inoculation, augmentation and conservation.
Mechanical controlThis is the procedure in which members of the pest species are trapped or killed by mechanical means, or are prevented from gaining access to the host plants by making barriers. Mechanical pest control has only limited application, though it is effective under certain circumstances. It is very effective in the initial stage of infestation of some insect pests, such as aphids, jassids, scale insects, etc. It can give spectacular results, if carried out as an organized campaign over a larger area.
Physical controlThis involves the deliberate modification of some physical factors to slow down the growth of pest population or to minimise or prevent pest infestation
Biopesticides are the organic pesticides obtained or prepared from living organisms. They are harmless to beneficial plants, but control the growth of harmful pests.
This PPT describes about the
What is pesticides?
Uses of pesticides.
Manufacturing Process.
Classification of pesticides.
Prevention of Pesticides.
Benefits of pesticides.
Eco-pesticides.
Agricultural inputs, list of agricultural inputs and Insecticide used in Bang...MD. ZANE ALAM
Agricultural inputs are defined as products permitted for use in organic farming. These include feedstuffs, fertilizers and permitted plant protection products as well as cleaning agents and additives used in food production.
Weighted average cost of all financing sources(Thus weight is give.pdfanilgoelslg
Weighted average cost of all financing sources
(Thus weight is given to all the sources of finance)
Solution
Weighted average cost of all financing sources
(Thus weight is given to all the sources of finance).
( 1) jirovecii tropozoites produce sexually by fission is a false st.pdfanilgoelslg
( 1) jirovecii tropozoites produce sexually by fission is a false statement.
(2) influenza,mycoplasma,rhinovirus,respiratory syncytial virus are responsible for respiratory
disease in infants.
Solution
( 1) jirovecii tropozoites produce sexually by fission is a false statement.
(2) influenza,mycoplasma,rhinovirus,respiratory syncytial virus are responsible for respiratory
disease in infants..
Zeff increases from rigght to left in a period, a.pdfanilgoelslg
Zeff increases from rigght to left in a period, and increases slightly from top to
bottom in a group.
Solution
Zeff increases from rigght to left in a period, and increases slightly from top to
bottom in a group..
What exactly was involved in the reaction Were y.pdfanilgoelslg
What exactly was involved in the reaction? Were you neutralizing an acid or a
base? Just adding bicarb to water? In any case My best guess would be CO2(g) NaHCO3 + H+
<==> Na+ + H2O + CO2
Solution
What exactly was involved in the reaction? Were you neutralizing an acid or a
base? Just adding bicarb to water? In any case My best guess would be CO2(g) NaHCO3 + H+
<==> Na+ + H2O + CO2.
True Infrared spectroscopy is one of the fastest.pdfanilgoelslg
True Infrared spectroscopy is one of the fastest methods for determining
information ... molecular structure on a wide variety of compounds. ... A typical organic ... As
you can see in the IR spectrum of 1-butanol, there are many short peaks
Solution
True Infrared spectroscopy is one of the fastest methods for determining
information ... molecular structure on a wide variety of compounds. ... A typical organic ... As
you can see in the IR spectrum of 1-butanol, there are many short peaks.
sp2 note; NO2- adopts a bent and planar geometry.pdfanilgoelslg
sp2 note; NO2- adopts a bent and planar geometry, thus it is sp2-hybridized.
Solution
sp2 note; NO2- adopts a bent and planar geometry, thus it is sp2-hybridized..
I2 is purple color. using oxidizing areagent to o.pdfanilgoelslg
I2 is purple color. using oxidizing areagent to oxdize NaI to I2. through color
change, you can judge if the salt contains I- ion or not. such as use H2SO4 to oxidize it. 2 Na+ +
2 I- + 2 H+ + 2 HSO4- <-> 2 Na+ + I2 + HSO3- + HSO4- + H2O.
Solution
I2 is purple color. using oxidizing areagent to oxdize NaI to I2. through color
change, you can judge if the salt contains I- ion or not. such as use H2SO4 to oxidize it. 2 Na+ +
2 I- + 2 H+ + 2 HSO4- <-> 2 Na+ + I2 + HSO3- + HSO4- + H2O..
conductivity of the solution is due to its ions. .pdfanilgoelslg
conductivity of the solution is due to its ions. The mobility of the ions in the
solution will cause the conductivity. If the no . of ions in the solution is more then the mobility of
the ions will be more there by the condictivity will be more. CaCl2 ----> Ca2+ + 2 Cl- totally
(1+2)=3 ions Fe(NO3)3 ----> Fe 3+ + 3 NO3 - totally (1+3) = 4 ions So No . of ions in
Fe(NIO3)3 will be more its conductivity will be more in solution.
Solution
conductivity of the solution is due to its ions. The mobility of the ions in the
solution will cause the conductivity. If the no . of ions in the solution is more then the mobility of
the ions will be more there by the condictivity will be more. CaCl2 ----> Ca2+ + 2 Cl- totally
(1+2)=3 ions Fe(NO3)3 ----> Fe 3+ + 3 NO3 - totally (1+3) = 4 ions So No . of ions in
Fe(NIO3)3 will be more its conductivity will be more in solution..
raised outcomes exists across several situations, as an example by .pdfanilgoelslg
raised outcomes exists across several situations, as an example: by analyzing patient
characteristics and also the price and outcomes of care to spot the foremost clinically and value
effective treatments and supply analysis and tools, thereby influencing supplier behavior;
applying advanced analytics to patient profiles (e.g., segmentation and prognostic modeling) to
proactively determine people WHO would like preventative care or way changes; broad scale
illness identification to spot prognostic events and support interference initiatives; assembling
and commercial enterprise knowledge on medical procedures, therefore aiding patients in crucial
the care protocols or regimens that provide the most effective value; distinctive, predicting and
minimizing fraud by implementing advanced analytic systems for fraud detection and checking
the accuracy and consistency of claims; and, implementing a lot of nearer to period, claim
authorization; making new revenue streams by aggregating and synthesizing patient clinical
records and claims knowledge sets to supply knowledge and services to 3rd parties, for example,
licensing knowledge to help pharmaceutical firms in distinctive patients for inclusion in clinical
trials. several payers square measure developing and deploying mobile apps that facilitate
patients manage their care, find suppliers and improve their health. Via analytics, payers square
measure able to monitor adherence to drug and treatment regimens and observe trends that result
in individual and population eudaemonia advantages [12, 16, 17, 18].
This article provides an outline of massive knowledge analytics in care because it is rising as a
discipline. First, we tend to outline and discuss the assorted blessings and characteristics of
massive knowledge analytics in care. Then we tend to describe the branch of knowledge
framework of massive knowledge analytics in care. Third, the massive knowledge analytics
application development methodology is delineate. Fourth, we offer samples of huge knowledge
analytics in care rumored within the literature. Fifth, the challenges square measure known.
Lastly, we provide conclusions and future directions.
Big knowledge analytics in care
Health knowledge volume is anticipated to grow dramatically within the years ahead [6].
additionally, care compensation models square measure changing; pregnant use and get
performance square measure rising as essential new factors in today’s care surroundings. though
profit isn\'t and may not be a primary incentive, it\'s vitally vital for care organizations to amass
the out there tools, infrastructure, and techniques to leverage huge knowledge effectively
alternatively risk losing doubtless scores of bucks in revenue and profits [19].
What precisely is huge data? A report delivered to the U.S. Congress in August 2012 defines
huge knowledge as “large volumes of high speed, complex, and variable knowledge that need
advanced techniques and technologies to alter the capt.
Q-1Ans-MAC address is a globally unique identifier assigned to n.pdfanilgoelslg
Q-1
Ans-
MAC address is a globally unique identifier assigned to network devices, and therefore it is often
referred to as hardware or physical address.
MAC addresses are 6-byte (48-bits) in length
Solution
Q-1
Ans-
MAC address is a globally unique identifier assigned to network devices, and therefore it is often
referred to as hardware or physical address.
MAC addresses are 6-byte (48-bits) in length.
Net neutrality is the principle that Internet service providers and .pdfanilgoelslg
Net neutrality is the principle that Internet service providers and governments regulating the
Internet should treat all data on the Internet the same, not discriminating or charging
differentially by user, content, website, platform, application, type of attached equipment, or
mode of communication.
supporters of net neutrality wants cable operators not to screen,interrupt or filter internet content
without a court order.
for example consider a case where companies X and Y are comepetitors, if there is no net
neutrality then if X gives money to cable companies the companies can make people accessing Y
experience unfortable by giving less speeds,bandwidth etc. website of X opens fast but Y\'s
website can be loaded slow or not lod at all.eliminating net neutrality may make internet just as
cable tv where the content will be made to user only if they pay for the service.and monopolistic
companies may take severe advantage. so cable companies have all advantages if net neutrality is
not passed.
Solution
Net neutrality is the principle that Internet service providers and governments regulating the
Internet should treat all data on the Internet the same, not discriminating or charging
differentially by user, content, website, platform, application, type of attached equipment, or
mode of communication.
supporters of net neutrality wants cable operators not to screen,interrupt or filter internet content
without a court order.
for example consider a case where companies X and Y are comepetitors, if there is no net
neutrality then if X gives money to cable companies the companies can make people accessing Y
experience unfortable by giving less speeds,bandwidth etc. website of X opens fast but Y\'s
website can be loaded slow or not lod at all.eliminating net neutrality may make internet just as
cable tv where the content will be made to user only if they pay for the service.and monopolistic
companies may take severe advantage. so cable companies have all advantages if net neutrality is
not passed..
Malnutrition people lacks energy so they interact less with the peop.pdfanilgoelslg
Malnutrition people lacks energy so they interact less with the people around them affecting the
mental, physical and cognitive development of that individual.
Solution
Malnutrition people lacks energy so they interact less with the people around them affecting the
mental, physical and cognitive development of that individual..
C. 10.0.0.65Host 10.0.0.65 is the device IP address of the host th.pdfanilgoelslg
C. 10.0.0.65
Host 10.0.0.65 is the device IP address of the host that accessed a web server on port 80.
Solution
C. 10.0.0.65
Host 10.0.0.65 is the device IP address of the host that accessed a web server on port 80..
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
1. Insecticide
An insecticide is a substance used to kill insects. They
include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are
used in agriculture, medicine, industry and by consumers. Insecticides are claimed to be a major
factor behind the increase in agricultural 20th century's productivity . Nearly all insecticides
have the potential to significantly alter ecosystems; many are toxic to humans; some concentrate
along the food chain.
Insecticides can be classified in two major groups: systemic insecticides, which have residual or
long term activity; and contact insecticides, which have no residual activity.
Furthermore, one can distinguish three types of insecticide. 1. Natural insecticides, such as
nicotine, pyrethrum and neem extracts, made by plants as defenses against insects. 2. Inorganic
insecticides, which are metals. 3. Organic insecticides, which are organic chemical compounds,
mostly working by contact.
The mode of action describes how the pesticide kills or inactivates a pest. It provides another
way of classifying insecticides. Mode of action is important in understanding whether an
insecticide will be toxic to unrelated species, such as fish, birds and mammals.
Insecticides are distinct from insect repellents, which do not kill.
activity
Systemic insecticides become incorporated and distributed systemically throughout the whole
plant. When insects feed on the plant, they ingest the insecticide. Systemic insecticides produced
by transgenic plants are called plant-incorporated protectants (PIPs). For instance, a gene that
codes for a specific Bacillus thuringiensis biocidal protein was introduced into corn and other
species. The plant manufactures the protein, which kills the insect when consumed .Contact
insecticides are toxic to insects upon direct contact. These can be inorganic insecticides, which
are metals and include arsenates, copper and fluorine compounds, which are less commonly
used, and the commonly used sulfur. Contact insecticides can be organic insecticides, i.e. organic
chemical compounds, synthetically produced, and comprising the largest numbers of pesticides
used today. Or they can be natural compounds like pyrethrum, neem oil etc. Contact insecticides
usually have no residual activity.
Efficacy can be related to the quality of pesticide application, with small droplets, such as
aerosols often improving performance.[4][better source needed]
Biological pesticides
Main article: Biopesticide
Many organic compounds are produced by plants for the purpose of defending the host plant
2. from predation. A trivial case is tree rosin, which is a natural insecticide. Specific, the production
of oleoresin by conifer species is a component of the defense response against insect attack and
fungal pathogen infection . Many fragrances, e.g. oil of wintergreen, are in fact antifeedants.
Four extracts of plants are in commercial use: pyrethrum, rotenone, neem oil, and various
essential oils
Other biological approaches
Plant-incorporated protectants
Transgenic crops that act as insecticides began in 1996 with a genetically modified potato that
produced the Cry protein, derived from the bacterium Bacillus thuringiensis, which is toxic to
beetle larvae such as the Colorado potato beetle. The technique has been expanded to include the
use of RNA interference RNAi that fatally silences crucial insect genes. RNAi likely evolved as
a defense against viruses. Midgut cells in many larvae take up the molecules and help spread the
signal. The technology can target only insects that have the silenced sequence, as was
demonstrated when a particular RNAi affected only one of four fruit fly species. The technique is
expected to replace many other insecticides, which are losing effectiveness due to the spread of
pesticide resistance
Enzymes
Many plants exude substances to repel insects. Premier examples are substances activated by the
enzyme myrosinase. This enzyme converts glucosinolates to various compounds that are toxic to
herbivorous insects. One product of this enzyme is allyl isothiocyanate, the pungent ingredient in
horseradish sauces.
Biosynthesis of antifeedants by the action of myrosinase.
The myrosinase is released only upon crushing the flesh of horseradish. Since allyl
isothiocyanate is harmful to the plant as well as the insect, it is stored in the harmless form of the
glucosinolate, separate from the myrosinase enzyme.
Bacterial
Bacillus thuringiensis is a bacterial disease that affects Lepidopterans and some other insects.
Toxins produced by strains of this bacterium are used as a larvicide against caterpillars, beetles,
and mosquitoes. Toxins from Saccharopolyspora spinosa are isolated from fermentations and
sold as Spinosad. Because these toxins have little effect on other organisms, they are considered
more environmentally friendly than synthetic pesticides. The toxin from B. thuringiensis (Bt
toxin) has been incorporated directly into plants through the use of genetic engineering. Other
biological insecticides include products based on entomopathogenic fungi (e.g., Beauveria
bassiana, Metarhizium anisopliae), nematodes (e.g., Steinernema feltiae) and viruses (e.g., Cydia
pomonella granulovirus).[citation needed]
Synthetic insecticide
3. A major emphasis of organic chemistry is the development of chemical tools to enhance
agricultural productivity. Insecticides represent a major area of emphasis. Many of the major
insecticides are inspired by biological analogues. Many others are completely alien to nature.
Organochlorides
The best known organochloride, DDT, was created by Swiss scientist Paul Müller. For this
discovery, he was awarded the 1948 Nobel Prize for Physiology or Medicine DDT was
introduced in 1944. It functions by opening sodium channels in the insect's nerve cells The
contemporaneous rise of the chemical industry facilitated large-scale production of DDT and
related chlorinated hydrocarbons.
Organophosphates and carbamates]
Organophosphates are another large class of contact insecticides. These also target the insect's
nervous system. Organophosphates interfere with the enzymesacetylcholinesterase and other
cholinesterases, disrupting nerve impulses and killing or disabling the insect. Organophosphate
insecticides and chemical warfare nerve agents (such as sarin, tabun, soman, and VX) work in
the same way. Organophosphates have a cumulative toxic effect to wildlife, so multiple
exposures to the chemicals amplifies the toxicity. In the US, organophosphate use declined with
the rise of substitutes. Carbamate insecticides have similar mechanisms to organophosphates, but
have a much shorter duration of action and are somewhat less toxic.[
Pyrethroids
Pyrethroid pesticides mimic the insecticidal activity of the natural compound pyrethrum, the
biopesticide found in pyrethrins. These compounds are nonpersistent sodium channel modulators
and are less toxic than organophosphates and carbamates. Compounds in this group are often
applied against household pests
Neonicotinoids
Neonicotinoids are synthetic analogues of the natural insecticide nicotine (with much lower acute
mammalian toxicity and greater field persistence). These chemicals are acetylcholine receptor
agonists. They are broad-spectrum systemic insecticides, with rapid action (minutes-hours). They
are applied as sprays, drenches, seed and soiltreatments. Treated insects exhibit leg tremors,
rapid wing motion, stylet withdrawal (aphids), disoriented movement, paralysis and death
.Imidacloprid may be the most common. It has recently come under scrutiny for allegedly
pernicious effects on honeybees. and its potential to increase the susceptibility of rice to
planthopper attacks.
Ryanoids
Ryanoids are synthetic analogues with the same mode of action as ryanodine, a naturally
occurring insecticide extracted from Ryania speciosa (Flacourtiaceae). They bind to calcium
channels in cardiac and skeletal muscle, blocking nerve transmission. Only one such insecticide
4. is currently registered, Rynaxypyr, generic name chlorantraniliprole.
Insect growth regulators
Insect growth regulator (IGR) is a term coined to include insect hormone mimics and an earlier
class of chemicals, the benzoylphenyl ureas, which inhibit chitin(exoskeleton) biosynthesis in
insects. Diflubenzuron is a member of the latter class, used primarily to control caterpillars that
are pests. The most successful insecticides in this class are the juvenoids (juvenile hormone
analogues). Of these, methoprene is most widely used. It has no observable acute toxicity in rats
and is approved by World Health Organization(WHO) for use in drinking water cisterns to
combat malaria. Most of its uses are to combat insects where the adult is the pest, including
mosquitoes, several fly species, and fleas. Two very similar products, hydroprene and kinoprene,
are used for controlling species such as cockroaches and white flies. Methoprene was registered
with the EPA in 1975. Virtually no reports of resistance have been filed. A more recent type of
IGR is the ecdysone agonist tebufenozide (MIMIC), which is used in forestry and other
applications for control of caterpillars, which are far more sensitive to its hormonal effects than
other insect orders.
Environmental Effects
Effects on nontarget species. Some insecticides kill or harm other creatures in addition to those
they are intended to kill. For example, birds may be poisoned when they eat food that was
recently sprayed with insecticides or when they mistake an insecticide granule on the ground for
food and eat it.
Sprayed insecticide may drift from the area to which it is applied and into wildlife areas,
especially when it is sprayed aerially.
DDT
Main article: DDT
The development of DDT was motivated by desire to replace more dangerous or less effective
alternatives. DDT was introduced to replace lead and arsenic-based compounds, which were in
widespread use in the early 1940s .DDT was brought to public attention by Rachel Carson's
book Silent Spring. One side-effect of DDT is to reduce the thickness of shells on the eggs of
predatory birds. The shells sometimes become too thin to be viable, reducing bird populations.
This occurs with DDT and related compounds due to the process of bioaccumulation, wherein
the chemical, due to its stability and fat solubility, accumulates in organisms' fatty tissues. Also,
DDT may biomagnify, which causes progressively higher concentrations in the body fat of
animals farther up the food chain. The near-worldwide ban on agricultural use of DDT and
related chemicals has allowed some of these birds, such as the peregrine falcon, to recover in
recent years. A number of organochlorine pesticides have been banned from most uses
worldwide. Globally they are controlled via the Stockholm Convention on persistent organic
5. pollutants. These include: aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, mirex and
toxaphene.[citation needed]
Pollinator decline
Insecticides can kill bees and may be a cause of pollinator decline, the loss of bees that pollinate
plants, and colony collapse disorder (CCD. in which worker bees from a beehive or Western
honey bee colony abruptly disappear. Loss of pollinators means a reduction in crop yields .
Sublethal doses of insecticides (i.e. imidacloprid and other neonicotinoids) affect bee foraging
behavior. However, research into the causes of CCD was inconclusive as of June 2007
Examples
Organochlorides]
See also: Category:Organochloride insecticides
Organophosphates
See also: Category:Organophosphate insecticides
CarbamatesAldicarb
PyrethroidsAllethrin
Neonicotinoids[]
RyanoidsChlorantraniliprole
Insect growth regulators]
Plant-derivedAnabasine
BiologicalsBacillus sphaericus
OtherDiatomaceous earth
Organochlorides]
See also: Category:Organochloride
insecticidesAldrinChlordaneChlordeconeDDTDieldrinEndosulfanEndrinHeptachlorHexachlorob
enzeneLindane (gamma-hexachlorocyclohexane)MethoxychlorMirexPentachlorophenolTDE
Organophosphates
See also: Category:Organophosphate insecticidesAcephateAzinphos-
methylBensulideChlorethoxyfosChlorpyrifosChlorpyriphos-methylDiazinonDichlorvos
(DDVP)DicrotophosDimethoateDisulfotonEthopropFenamiphosFenitrothionFenthionFosthiazate
MalathionMethamidophosMethidathionMevinphosMonocrotophosNaledOmethoateOxydemeton
-methylParathionParathion-methylPhoratePhosalonePhosmetPhostebupirimPhoximPirimiphos-
methylProfenofosTerbufosTetrachlorvinphosTribufosTrichlorfon
CarbamatesAldicarbBendiocarbCarbofuranCarbarylDioxacarbFenobucarbFenoxycarbIsoprocarb
Methomyl2-(1-Methylpropyl)phenyl methylcarbamate
PyrethroidsAllethrinBifenthrinCyhalothrin, Lambda-
cyhalothrinCypermethrinCyfluthrinDeltamethrinEtofenproxFenvaleratePermethrinPhenothrinPra
6. llethrinResmethrinTetramethrinTralomethrinTransfluthrin
Neonicotinoids[]AcetamipridClothianidinImidaclopridNithiazineThiaclopridThiamethoxam
RyanoidsChlorantraniliproleCyantraniliproleFlubendiamide
Insect growth regulators]Benzoylureas
DiflubenzuronFlufenoxuronCyromazineMethopreneHydropreneTebufenozide
Plant-derivedAnabasineAnethole (mosquito larvae)[22]AnnoninAsimina (pawpaw tree seeds) for
liceAzadirachtinCaffeineCarapaCinnamaldehyde (very effective for killing mosquito
larvae)[23]Cinnamon leaf oil (very effective for killing mosquito larvae)[22]Cinnamyl acetate
(kills mosquito larvae)[22]CitralDeguelinDerrisDerris (rotenone)Desmodium caudatum (leaves
and roots)Eugenol (mosquito larvae)[22]LinaloolMyristicinNeem
(Azadirachtin)NicotinePeganum harmala, seeds (smoke from), rootOregano oil kills beetles
Rhizopertha dominica[24] (bug found in stored cereal)PolyketidePyrethrumQuassia (South
American plant genus)RyanodineTetranortriterpenoidThymol (controls varroa mites in bee
colonies)[25]
BiologicalsBacillus sphaericusBacillus thuringiensisBacillus thuringiensis aizawiBacillus
thuringiensis israelensisBacillus thuringiensis kurstakiBacillus thuringiensis tenebrionisNuclear
Polyhedrosis virusGranulovirusSpinosad AKA Spinosyn ASpinosyn DLecanicillium lecanii
OtherDiatomaceous earthBorate
Solution
Insecticide
An insecticide is a substance used to kill insects. They
include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are
used in agriculture, medicine, industry and by consumers. Insecticides are claimed to be a major
factor behind the increase in agricultural 20th century's productivity . Nearly all insecticides
have the potential to significantly alter ecosystems; many are toxic to humans; some concentrate
along the food chain.
Insecticides can be classified in two major groups: systemic insecticides, which have residual or
long term activity; and contact insecticides, which have no residual activity.
Furthermore, one can distinguish three types of insecticide. 1. Natural insecticides, such as
nicotine, pyrethrum and neem extracts, made by plants as defenses against insects. 2. Inorganic
insecticides, which are metals. 3. Organic insecticides, which are organic chemical compounds,
mostly working by contact.
The mode of action describes how the pesticide kills or inactivates a pest. It provides another
7. way of classifying insecticides. Mode of action is important in understanding whether an
insecticide will be toxic to unrelated species, such as fish, birds and mammals.
Insecticides are distinct from insect repellents, which do not kill.
activity
Systemic insecticides become incorporated and distributed systemically throughout the whole
plant. When insects feed on the plant, they ingest the insecticide. Systemic insecticides produced
by transgenic plants are called plant-incorporated protectants (PIPs). For instance, a gene that
codes for a specific Bacillus thuringiensis biocidal protein was introduced into corn and other
species. The plant manufactures the protein, which kills the insect when consumed .Contact
insecticides are toxic to insects upon direct contact. These can be inorganic insecticides, which
are metals and include arsenates, copper and fluorine compounds, which are less commonly
used, and the commonly used sulfur. Contact insecticides can be organic insecticides, i.e. organic
chemical compounds, synthetically produced, and comprising the largest numbers of pesticides
used today. Or they can be natural compounds like pyrethrum, neem oil etc. Contact insecticides
usually have no residual activity.
Efficacy can be related to the quality of pesticide application, with small droplets, such as
aerosols often improving performance.[4][better source needed]
Biological pesticides
Main article: Biopesticide
Many organic compounds are produced by plants for the purpose of defending the host plant
from predation. A trivial case is tree rosin, which is a natural insecticide. Specific, the production
of oleoresin by conifer species is a component of the defense response against insect attack and
fungal pathogen infection . Many fragrances, e.g. oil of wintergreen, are in fact antifeedants.
Four extracts of plants are in commercial use: pyrethrum, rotenone, neem oil, and various
essential oils
Other biological approaches
Plant-incorporated protectants
Transgenic crops that act as insecticides began in 1996 with a genetically modified potato that
produced the Cry protein, derived from the bacterium Bacillus thuringiensis, which is toxic to
beetle larvae such as the Colorado potato beetle. The technique has been expanded to include the
use of RNA interference RNAi that fatally silences crucial insect genes. RNAi likely evolved as
a defense against viruses. Midgut cells in many larvae take up the molecules and help spread the
signal. The technology can target only insects that have the silenced sequence, as was
demonstrated when a particular RNAi affected only one of four fruit fly species. The technique is
expected to replace many other insecticides, which are losing effectiveness due to the spread of
pesticide resistance
8. Enzymes
Many plants exude substances to repel insects. Premier examples are substances activated by the
enzyme myrosinase. This enzyme converts glucosinolates to various compounds that are toxic to
herbivorous insects. One product of this enzyme is allyl isothiocyanate, the pungent ingredient in
horseradish sauces.
Biosynthesis of antifeedants by the action of myrosinase.
The myrosinase is released only upon crushing the flesh of horseradish. Since allyl
isothiocyanate is harmful to the plant as well as the insect, it is stored in the harmless form of the
glucosinolate, separate from the myrosinase enzyme.
Bacterial
Bacillus thuringiensis is a bacterial disease that affects Lepidopterans and some other insects.
Toxins produced by strains of this bacterium are used as a larvicide against caterpillars, beetles,
and mosquitoes. Toxins from Saccharopolyspora spinosa are isolated from fermentations and
sold as Spinosad. Because these toxins have little effect on other organisms, they are considered
more environmentally friendly than synthetic pesticides. The toxin from B. thuringiensis (Bt
toxin) has been incorporated directly into plants through the use of genetic engineering. Other
biological insecticides include products based on entomopathogenic fungi (e.g., Beauveria
bassiana, Metarhizium anisopliae), nematodes (e.g., Steinernema feltiae) and viruses (e.g., Cydia
pomonella granulovirus).[citation needed]
Synthetic insecticide
A major emphasis of organic chemistry is the development of chemical tools to enhance
agricultural productivity. Insecticides represent a major area of emphasis. Many of the major
insecticides are inspired by biological analogues. Many others are completely alien to nature.
Organochlorides
The best known organochloride, DDT, was created by Swiss scientist Paul Müller. For this
discovery, he was awarded the 1948 Nobel Prize for Physiology or Medicine DDT was
introduced in 1944. It functions by opening sodium channels in the insect's nerve cells The
contemporaneous rise of the chemical industry facilitated large-scale production of DDT and
related chlorinated hydrocarbons.
Organophosphates and carbamates]
Organophosphates are another large class of contact insecticides. These also target the insect's
nervous system. Organophosphates interfere with the enzymesacetylcholinesterase and other
cholinesterases, disrupting nerve impulses and killing or disabling the insect. Organophosphate
insecticides and chemical warfare nerve agents (such as sarin, tabun, soman, and VX) work in
the same way. Organophosphates have a cumulative toxic effect to wildlife, so multiple
exposures to the chemicals amplifies the toxicity. In the US, organophosphate use declined with
9. the rise of substitutes. Carbamate insecticides have similar mechanisms to organophosphates, but
have a much shorter duration of action and are somewhat less toxic.[
Pyrethroids
Pyrethroid pesticides mimic the insecticidal activity of the natural compound pyrethrum, the
biopesticide found in pyrethrins. These compounds are nonpersistent sodium channel modulators
and are less toxic than organophosphates and carbamates. Compounds in this group are often
applied against household pests
Neonicotinoids
Neonicotinoids are synthetic analogues of the natural insecticide nicotine (with much lower acute
mammalian toxicity and greater field persistence). These chemicals are acetylcholine receptor
agonists. They are broad-spectrum systemic insecticides, with rapid action (minutes-hours). They
are applied as sprays, drenches, seed and soiltreatments. Treated insects exhibit leg tremors,
rapid wing motion, stylet withdrawal (aphids), disoriented movement, paralysis and death
.Imidacloprid may be the most common. It has recently come under scrutiny for allegedly
pernicious effects on honeybees. and its potential to increase the susceptibility of rice to
planthopper attacks.
Ryanoids
Ryanoids are synthetic analogues with the same mode of action as ryanodine, a naturally
occurring insecticide extracted from Ryania speciosa (Flacourtiaceae). They bind to calcium
channels in cardiac and skeletal muscle, blocking nerve transmission. Only one such insecticide
is currently registered, Rynaxypyr, generic name chlorantraniliprole.
Insect growth regulators
Insect growth regulator (IGR) is a term coined to include insect hormone mimics and an earlier
class of chemicals, the benzoylphenyl ureas, which inhibit chitin(exoskeleton) biosynthesis in
insects. Diflubenzuron is a member of the latter class, used primarily to control caterpillars that
are pests. The most successful insecticides in this class are the juvenoids (juvenile hormone
analogues). Of these, methoprene is most widely used. It has no observable acute toxicity in rats
and is approved by World Health Organization(WHO) for use in drinking water cisterns to
combat malaria. Most of its uses are to combat insects where the adult is the pest, including
mosquitoes, several fly species, and fleas. Two very similar products, hydroprene and kinoprene,
are used for controlling species such as cockroaches and white flies. Methoprene was registered
with the EPA in 1975. Virtually no reports of resistance have been filed. A more recent type of
IGR is the ecdysone agonist tebufenozide (MIMIC), which is used in forestry and other
applications for control of caterpillars, which are far more sensitive to its hormonal effects than
other insect orders.
Environmental Effects
10. Effects on nontarget species. Some insecticides kill or harm other creatures in addition to those
they are intended to kill. For example, birds may be poisoned when they eat food that was
recently sprayed with insecticides or when they mistake an insecticide granule on the ground for
food and eat it.
Sprayed insecticide may drift from the area to which it is applied and into wildlife areas,
especially when it is sprayed aerially.
DDT
Main article: DDT
The development of DDT was motivated by desire to replace more dangerous or less effective
alternatives. DDT was introduced to replace lead and arsenic-based compounds, which were in
widespread use in the early 1940s .DDT was brought to public attention by Rachel Carson's
book Silent Spring. One side-effect of DDT is to reduce the thickness of shells on the eggs of
predatory birds. The shells sometimes become too thin to be viable, reducing bird populations.
This occurs with DDT and related compounds due to the process of bioaccumulation, wherein
the chemical, due to its stability and fat solubility, accumulates in organisms' fatty tissues. Also,
DDT may biomagnify, which causes progressively higher concentrations in the body fat of
animals farther up the food chain. The near-worldwide ban on agricultural use of DDT and
related chemicals has allowed some of these birds, such as the peregrine falcon, to recover in
recent years. A number of organochlorine pesticides have been banned from most uses
worldwide. Globally they are controlled via the Stockholm Convention on persistent organic
pollutants. These include: aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, mirex and
toxaphene.[citation needed]
Pollinator decline
Insecticides can kill bees and may be a cause of pollinator decline, the loss of bees that pollinate
plants, and colony collapse disorder (CCD. in which worker bees from a beehive or Western
honey bee colony abruptly disappear. Loss of pollinators means a reduction in crop yields .
Sublethal doses of insecticides (i.e. imidacloprid and other neonicotinoids) affect bee foraging
behavior. However, research into the causes of CCD was inconclusive as of June 2007
Examples
Organochlorides]
See also: Category:Organochloride insecticides
Organophosphates
See also: Category:Organophosphate insecticides
CarbamatesAldicarb
PyrethroidsAllethrin
Neonicotinoids[]
11. RyanoidsChlorantraniliprole
Insect growth regulators]
Plant-derivedAnabasine
BiologicalsBacillus sphaericus
OtherDiatomaceous earth
Organochlorides]
See also: Category:Organochloride
insecticidesAldrinChlordaneChlordeconeDDTDieldrinEndosulfanEndrinHeptachlorHexachlorob
enzeneLindane (gamma-hexachlorocyclohexane)MethoxychlorMirexPentachlorophenolTDE
Organophosphates
See also: Category:Organophosphate insecticidesAcephateAzinphos-
methylBensulideChlorethoxyfosChlorpyrifosChlorpyriphos-methylDiazinonDichlorvos
(DDVP)DicrotophosDimethoateDisulfotonEthopropFenamiphosFenitrothionFenthionFosthiazate
MalathionMethamidophosMethidathionMevinphosMonocrotophosNaledOmethoateOxydemeton
-methylParathionParathion-methylPhoratePhosalonePhosmetPhostebupirimPhoximPirimiphos-
methylProfenofosTerbufosTetrachlorvinphosTribufosTrichlorfon
CarbamatesAldicarbBendiocarbCarbofuranCarbarylDioxacarbFenobucarbFenoxycarbIsoprocarb
Methomyl2-(1-Methylpropyl)phenyl methylcarbamate
PyrethroidsAllethrinBifenthrinCyhalothrin, Lambda-
cyhalothrinCypermethrinCyfluthrinDeltamethrinEtofenproxFenvaleratePermethrinPhenothrinPra
llethrinResmethrinTetramethrinTralomethrinTransfluthrin
Neonicotinoids[]AcetamipridClothianidinImidaclopridNithiazineThiaclopridThiamethoxam
RyanoidsChlorantraniliproleCyantraniliproleFlubendiamide
Insect growth regulators]Benzoylureas
DiflubenzuronFlufenoxuronCyromazineMethopreneHydropreneTebufenozide
Plant-derivedAnabasineAnethole (mosquito larvae)[22]AnnoninAsimina (pawpaw tree seeds) for
liceAzadirachtinCaffeineCarapaCinnamaldehyde (very effective for killing mosquito
larvae)[23]Cinnamon leaf oil (very effective for killing mosquito larvae)[22]Cinnamyl acetate
(kills mosquito larvae)[22]CitralDeguelinDerrisDerris (rotenone)Desmodium caudatum (leaves
and roots)Eugenol (mosquito larvae)[22]LinaloolMyristicinNeem
(Azadirachtin)NicotinePeganum harmala, seeds (smoke from), rootOregano oil kills beetles
Rhizopertha dominica[24] (bug found in stored cereal)PolyketidePyrethrumQuassia (South
American plant genus)RyanodineTetranortriterpenoidThymol (controls varroa mites in bee
colonies)[25]
BiologicalsBacillus sphaericusBacillus thuringiensisBacillus thuringiensis aizawiBacillus
thuringiensis israelensisBacillus thuringiensis kurstakiBacillus thuringiensis tenebrionisNuclear