Introduction Introduction to to Agricultural Entomology Agricultural Entomology Eric Stormer Eric Stormer Virginia Cooperative Virginia Cooperative Extension Extension
1. IntroductionIntroduction toto Agricultural
EntomologyAgricultural Entomology Eric StormerEric Stormer Virginia
Cooperative ExtensionVirginia Cooperative Extension
3. What is Entomology?What is Entomology? EntomologyEntomology
is theis the study of insects.study of insects. AnAn
EntomologistEntomologist is ais a scientist who studiesscientist
who studies insects.insects.
4. Insect FactsInsect Facts More than 750,000 species have
beenMore than 750,000 species have been identified.identified.
Approximately two million species haveApproximately two million
species have not been described or identified.not been described or
identified. About 10,000 species are harmful toAbout 10,000 species
are harmful to humans.humans. About 500 are considered major pests
inAbout 500 are considered major pests in the USA.the USA.
5. Insects Impact On HumansInsects Impact On Humans Have
hindered workHave hindered work (Malaria, Panama(Malaria, Panama
Canal).Canal).
6. Insects Impact on HumansInsects Impact on Humans Have caused
wide spread epidemics - BubonicHave caused wide spread epidemics -
Bubonic Plague, 14th century Europe.Plague, 14th century
Europe.
7. Insects Impacts on HumansInsects Impacts on Humans Swarms
(plagues) devastated crops, causedSwarms (plagues) devastated
crops, caused widespread famine.widespread famine.
8. Insects Impact on HumansInsects Impact on Humans
9. Insects Impact on HumansInsects Impact on Humans Encourage
diversification of crops (cotton, bollEncourage diversification of
crops (cotton, boll weevils, peanuts).weevils, peanuts).
10. Impact of InsectsImpact of Insects Contributed
toContributed to the discovery ofthe discovery of America -
tradeAmerica - trade routes to the Eastroutes to the East for
silk.for silk.
11. Insects Impact, ContdInsects Impact, Contd Invade our
homes.Invade our homes. Spoil our food.Spoil our food. Destroy
ourDestroy our belongings.belongings. Cause us discomfort.Cause us
discomfort. Pollinate flowers ofPollinate flowers of our crops,
that we useour crops, that we use for food and fiber.for food and
fiber.
12. Scientific Classification of InsectsScientific
Classification of Insects Kingdom:Kingdom: AnimaliaAnimalia
Phylum:Phylum: ArthropodaArthropoda Class:Class: InsectaInsecta
Order:Order: 30+ exist30+ exist Binomial:Binomial: Genus,
speciesGenus, species Example:Example: Apis melliferaApis mellifera
(Honeybee)(Honeybee)
13. Six Orders that damage plantsSix Orders that damage plants
Orthoptera Orthoptera grasshoppers, locusts.grasshoppers, locusts.
Hemiptera Hemiptera bugs.bugs. Lepidoptera Lepidoptera moths and
butterflies.moths and butterflies. Homoptera Homoptera includes
aphids.includes aphids. Thysanoptera Thysanoptera includes
thrips.includes thrips. Coleoptera Coleoptera largest of alllargest
of all orders,orders, includes beetles.includes beetles.
14. Insect groupings by methods ofInsect groupings by methods
of feedingfeeding Chewing insects use mandibles to tear offChewing
insects use mandibles to tear off and grind up food (grasshoppers,
beetles).and grind up food (grasshoppers, beetles). Chewing-lapping
mouths used to lap upChewing-lapping mouths used to lap up liquid
(bumblebees, honeybees).liquid (bumblebees, honeybees).
Rasping-sucking mounts scrape off cellsRasping-sucking mounts
scrape off cells and particles from a plant surface andand
particles from a plant surface and suck the pieces into their
mouths (thrips).suck the pieces into their mouths (thrips).
15. Insect groupings by methods ofInsect groupings by methods
of feeding, contd.feeding, contd. Siphoning insects have a
straw-likeSiphoning insects have a straw-like mouth, called a
proboscis, to suck upmouth, called a proboscis, to suck up nectar
from flowers (moths, butterflies).nectar from flowers (moths,
butterflies). Piercing-sucking have a proboscis toPiercing-sucking
have a proboscis to pierce tissue surfaces, and feed on sappierce
tissue surfaces, and feed on sap from the plant (scale
insects).from the plant (scale insects). Sponging insects use
sponge-likeSponging insects use sponge-like appendage to absorb
liquid nourishmentappendage to absorb liquid nourishment
(non-biting flies).(non-biting flies).
16. Characteristics of InsectsCharacteristics of Insects
Exoskeleton - aExoskeleton - a skeleton that isskeleton that is on
the outside ofon the outside of an animal madean animal made of
chitin.of chitin.
17. Characteristics of InsectsCharacteristics of Insects Head
-Head - Pair of compoundPair of compound eyes.eyes. Two sensoryTwo
sensory appendagesappendages (antennae).(antennae).
18. Characteristics of InsectsCharacteristics of Insects
ThoraxThorax Has three body segmentsHas three body segments Has
three pairs of legs, attached hereHas three pairs of legs, attached
here Wings are attached here, depending on speciesWings are
attached here, depending on species
19. Characteristics, Contd.Characteristics, Contd. Abdomen
attached to the thorax, segmented.Abdomen attached to the thorax,
segmented.
20. Life Cycles of InsectsLife Cycles of Insects The physical
form of insects changes atThe physical form of insects changes at
different stages of their lives. Thisdifferent stages of their
lives. This process is calledprocess is called
metamorphosismetamorphosis.. Not all insects go through
metamorphosis;Not all insects go through metamorphosis; some
insects molt a process where thesome insects molt a process where
the insect outgrows its outer covering, shedsinsect outgrows its
outer covering, sheds it, and grows a new one.it, and grows a new
one. InstarsInstars are theare the stages of development between
molts.stages of development between molts.
21. Metamorphosis 3 stagesMetamorphosis 3 stages Larval
stageLarval stage insect has soft, worm-like insect has soft,
worm-like tubular body. Eat voraciously; capable oftubular body.
Eat voraciously; capable of extensive damage to
plants/crops.extensive damage to plants/crops. Pupal stagePupal
stage relatively dormant, relatively dormant, intermediate stage
between being a larvaintermediate stage between being a larva and
an adult during which body tissuesand an adult during which body
tissues are converted.are converted. Adult stageAdult stage insect
mates, lays eggs, insect mates, lays eggs, cycle begins again.cycle
begins again.
22. Complete MetamorphosisComplete Metamorphosis
23. Incomplete MetamorphosisIncomplete Metamorphosis Incomplete
metamorphosis is a processIncomplete metamorphosis is a process
whereby insects go from an egg to a formwhereby insects go from an
egg to a form called a naiad which looks and functionscalled a
naiad which looks and functions differently than an adult. When
this growthdifferently than an adult. When this growth process is
complete, the insect changes toprocess is complete, the insect
changes to a winged adult. Examples: dragonflies,a winged adult.
Examples: dragonflies, damselflies.damselflies.
25. Gradual MetamorphosisGradual Metamorphosis In gradual
metamorphosis, the immatureIn gradual metamorphosis, the immature
insects hatches from an egg and looksinsects hatches from an egg
and looks very much like the adult. These newlyvery much like the
adult. These newly hatched insects are referred to ashatched
insects are referred to as nymphs.nymphs. The nymph has different
feeding habitsThe nymph has different feeding habits and may live
in different places than theand may live in different places than
the adults.adults. From the nymph stage, insects grow intoFrom the
nymph stage, insects grow into adulthood. Ex: Roaches,
Grasshoppers.adulthood. Ex: Roaches, Grasshoppers.
26. Gradual MetamorphosisGradual Metamorphosis
27. Insect PestsInsect Pests Phytophagous InsectsPhytophagous
Insects (phyto = plant, (phyto = plant, phagous = eating).phagous =
eating). Phytophagous Insects eat leaves, stems,Phytophagous
Insects eat leaves, stems, fruits and roots of plants, and may
alsofruits and roots of plants, and may also carry diseases caused
by bacterial, viralcarry diseases caused by bacterial, viral and
fungal pathogens.and fungal pathogens. PathogenPathogen a living,
microscopic, disease- a living, microscopic, disease- producing
agent.producing agent.
28. PhytophagousPhytophagous InsectsInsects
29. PredatoryPredatory InsectsInsects
30. Insect Pests of AnimalsInsect Pests of Animals
ParasitismParasitism a relationship beneficial to a relationship
beneficial to one organism and harmful to the other.one organism
and harmful to the other. ParasiteParasite an organism that
practices an organism that practices parasitism; lives off of
anotherparasitism; lives off of another
organism/animal.organism/animal. Parasites may beParasites may be
externalexternal oror internalinternal (live(live outside of the
host, or inside of the host).outside of the host, or inside of the
host).
31. Challenges of Controlling InsectsChallenges of Controlling
Insects Insects are prolific; reproduce often andInsects are
prolific; reproduce often and produce large numbers of
young.produce large numbers of young. One female insect may lay
millions ofOne female insect may lay millions of eggs during her
lifetime.eggs during her lifetime. Certain insects produce as many
as 30Certain insects produce as many as 30 generations per
year.generations per year.
32. Insect Control MethodsInsect Control Methods Natural
Control birds, bats, predatoryNatural Control birds, bats,
predatory insects (ladybugs, wasps), mammals,insects (ladybugs,
wasps), mammals, toads, frogs (amphibians), fish.toads, frogs
(amphibians), fish. WeatherWeather DiseasesDiseases
33. Insect Control Methods, Contd.Insect Control Methods,
Contd. Chemical Control Chemical Control Has been used since
ancient times. Example: 200Has been used since ancient times.
Example: 200 B.C. Romans used bitumen on grape vines,B.C. Romans
used bitumen on grape vines, hellebore to treat body lice; Chinese
used arsenichellebore to treat body lice; Chinese used arsenic for
pests; 1800s nicotine, copper sulphate,for pests; 1800s nicotine,
copper sulphate, arsenic, paris green (copper compound); 1930
arsenic, paris green (copper compound); 1930 1950, DDT used to
control disease carrying1950, DDT used to control disease carrying
mosquitoes (malaria, yellow fever, typhus).mosquitoes (malaria,
yellow fever, typhus).
34. DDTDDT
35. Problems with Chemical PesticidesProblems with Chemical
Pesticides Can affect reproduction of animals;Can affect
reproduction of animals; bioconcentrates buildup of pesticides
inbioconcentrates buildup of pesticides in animals (particularly
true of hydrocarbons).animals (particularly true of hydrocarbons).
HydrocarbonsHydrocarbons last a very long time in thelast a very
long time in the environment. (Hydrocarbons are a group
ofenvironment. (Hydrocarbons are a group of chemical pesticides,
including DDT, Chlordane,chemical pesticides, including DDT,
Chlordane, Heptachlor and Toxaphene.) HydrocarbonsHeptachlor and
Toxaphene.) Hydrocarbons dont break down into less harmful
substancesdont break down into less harmful substances
easily.easily.
36. Problems with Chemical PesticidesProblems with Chemical
Pesticides Hydrocarbons can enter, and be passed up,
thruHydrocarbons can enter, and be passed up, thru the food
chain.the food chain. Most hydrocarbons are now banned in theMost
hydrocarbons are now banned in the United States.United
States.
37. Other Chemical PesticidesOther Chemical Pesticides
OrganophosphatesOrganophosphates A class of insecticides which
break downA class of insecticides which break down quickly and pose
less threat to thequickly and pose less threat to the environment
than do chlorinatedenvironment than do chlorinated hydrocarbons.
Includes: diazinon, parathion,hydrocarbons. Includes: diazinon,
parathion, malathion,malathion,
38. Other Chemical PesticidesOther Chemical Pesticides
Carbamates another class of chemicalCarbamates another class of
chemical pesticides, less toxic to humans and otherpesticides, less
toxic to humans and other warm-blooded animals. Includes
carbaryl,warm-blooded animals. Includes carbaryl,
(Sevin).(Sevin).
39. Regulating PesticidesRegulating Pesticides The
Environmental Protection AgencyThe Environmental Protection Agency
(EPA) regulates pesticides.(EPA) regulates pesticides. New
pesticides require about 10 years ofNew pesticides require about 10
years of testing before being approved for use.testing before being
approved for use. Must be safe to manufacture.Must be safe to
manufacture. Must not be harmful to the environmentMust not be
harmful to the environment when used according to directions.when
used according to directions. Crop pesticide residues must break
downCrop pesticide residues must break down quickly.quickly. Must
be labeled.Must be labeled.
40. Integrated Pest ManagementIntegrated Pest Management The
most modern method of pestThe most modern method of pest management
is a multi-facetedmanagement is a multi-faceted (integrated)
approach.(integrated) approach. IPM uses a wide variety of
approaches inIPM uses a wide variety of approaches in coordination
with each other.coordination with each other.
41. IPM MethodsIPM Methods Cultural Methods control methods
usedCultural Methods control methods used during a plants most
vulnerable stage(s) ofduring a plants most vulnerable stage(s) of
growth.growth. Cultural Methods are only used whenCultural Methods
are only used when needed; require close monitoring of theneeded;
require close monitoring of the plants for insect buildups. Also
used forplants for insect buildups. Also used for controlling
weeds. Example: plowingcontrolling weeds. Example: plowing under
crops after harvest to destroyunder crops after harvest to destroy
overwintering insects/habitats.overwintering insects/habitats.
42. IPM Methods, Contd.IPM Methods, Contd. Insect Diseases
andInsect Diseases and Predators thePredators the encouraging of
birds andencouraging of birds and other predator insects toother
predator insects to lower pest insectlower pest insect
populations.populations. Examples:Examples: BacillusBacillus
thuriengensisthuriengensis (Bt) spores(Bt) spores to control larval
insectto control larval insect forms, parasitic waspsforms,
parasitic wasps ((Encarsia sppEncarsia spp.).)
43. IPM Methods, Contd.IPM Methods, Contd. PheromonesPheromones
chemicals secreted by chemicals secreted by insects to communicate,
for example, toinsects to communicate, for example, to attract a
mate.attract a mate. Fields may be sprayed with pheromonesFields
may be sprayed with pheromones to disorient males seeking
females.to disorient males seeking females. Traps may be baited
with pheromones toTraps may be baited with pheromones to interrupt
reproduction.interrupt reproduction.
44. IPM Methods, Contd.IPM Methods, Contd. Release of sterile
males males treatedRelease of sterile males males treated with
radiation or other treatment arewith radiation or other treatment
are rendered sterile. They are then releasedrendered sterile. They
are then released in large quantities. Mating yields noin large
quantities. Mating yields no offspring.offspring.
45. IPM Methods, Contd.IPM Methods, Contd. Use of Insect
Resistant Plant Varieties Use of Insect Resistant Plant Varieties
this involves using genetic engineering tothis involves using
genetic engineering to create plants which insects dont like
tocreate plants which insects dont like to feed on. This method
holds greatfeed on. This method holds great potential for the
future.potential for the future.