Entom Presentation

7/31/2019 Entom Presentation

1/37

What is Forest Entomology

Branch of zoology that deals

with the study of forest

insects

It is an organized study to

obtain knowledge of all

phases ofinsect life and tounderstand insects role in

nature.


2/37

The Insecta (insects) are a Class of the large animal Phylum

called ARTHROPODA (arthropods) - a name that refers tothe jointed limbs.

Term insect came from greek word insecare which means

to cut into

CLASS MAIN BODY REGIONS PAIRS OF

LEGS

PAIRS OF

ANTENNAE

WINGS

CRUSTACEA two - cephalothorax* and

abdomen (some with

head and trunk)

five or more two Absent

MYRIAPODA two - head and trunk many - one

or two per

trunksegment

one Absent

ARACHNIDA two - cephalothorax* and

abdomen

four none (though palps

may resemble

antennae or legs)

Absent

INSECTA three - head, thorax and

abdomen

three one usually present

(but many

wingless forms
http://www.kendall-bioresearch.co.uk/class.htmhttp://www.kendall-bioresearch.co.uk/class.htmhttp://www.kendall-bioresearch.co.uk/class.htmhttp://www.kendall-bioresearch.co.uk/class.htmhttp://www.kendall-bioresearch.co.uk/class.htmhttp://www.kendall-bioresearch.co.uk/class.htmhttp://www.kendall-bioresearch.co.uk/class.htmhttp://www.kendall-bioresearch.co.uk/class.htm


3/37

based on numbers and biomass insects are

dubbed as the most successful animals on

earth. Considered as conquerors of the land.

Attributed by:1. Body architecture integument that is light and

strong

Shells (cuticle) helps prevent water loss.

jointed appendages, adapted into legs for

locomotion, mouthparts for feeding, structures ofreproduction and other uses.


4/37

Small size facilitates dispersal, escape from birdsand other predators and enables them to use foodpresent only in small amounts.

Ability to fly aids further in escaping and indispersal. This dispersal promotes colonization of newhabitats, which in turn promotes the evolution ofnew species.

Reproductive capacity ability to persist even inunfavorable environments. ability to lay largenumbers of eggs, combined with relatively short

generation time, produces a great amount of geneticof genetic variability that can be tested against theenvironment. The result is rapid adaptation ofpopulations to changing environmental conditions andformation of new species

Survivability--------


5/37

SubclassPTERYGOTA1. Division EXOPTERYGOTA

These are winged insects, although somehave lost their wings during the course of

evolution.When present, the wingsdevelop externally and there is no markedchange (metamorphosis) during the lifecycle. The young stages, called nymphs,resemble the adults except in size and inlacking fully-developed wings - simply

metamorphosis.2. Division EXOPTERYGOTA

These are winged insects, although somehave lost their wings during the course ofevolution.When present, the wingsdevelop externally and there is no marked

change (metamorphosis) during the lifecycle. The young stages, called nymphs,resemble the adults except in size and inlacking fully-developed wings - simplymetamorphosis.

Sub classAPTERYGOTA

These are winglessinsects and theirbody structuresuggests that they

have never had wingsduring theirevolutionary history.Young stagesresemble the adults -little or no

metamorphosis.


6/37

The insect body is composed

of three divisions:

a. head

b. thorax

c. abdomen

Tagmosis The grouping of

segments into functional

regions

Cranium- the hardened capsule

with an opening leading to the

mouth and thorax.


7/37

1. Head is a structurespecialized for feedingand for sensing andintegrating informationabout theenvironment.

-Made up ofcranium which bears

mouthparts, antennaeand eyes, and a shortneck called cervix.


8/37

1. hypognathus.mouthparts pointeddown,

2. prognathus

mouthparts pointedforward,

3. opisthognathus-mouthparts pointed

backward


9/37

chewing mouthparts-

grasshoppers ( jaws called

mandibles)

piercing-sucking mouthparts -

cicadas, aphids, mosquitoes

siphoning butterflies and

moths.

a long proboscis (tubular

tounge) composed of

maxillary elements forms a

tube through which a food

passes. the tube is held in

coiled spring when not in use.

Sponging/lapping mouthparts-

houseflies (spongy pad called

labellum)


10/37

These are movable and

contain sensory structuresthat allow insects to detectodors, vibrations and otherenvironmental stimuli.

The antenna is divided into

3 parts: 1. scape the basal

segment that articulateswith the head capsule

2. Pedicel the second

antennal segment 3. Flagellum tip

usually of severalsubsegments.


11/37

Filiform (threadlike)

Serrate (sawlike)

Moniliform (beadlike)

Clavate (club-shaped) capitate (head-shaped)

lamellate (platelike)

pectinate (comb-shaped) plumose (feather like


12/37

An insects head is typically

dominated by two bulging

compund eyes that aredivided into many six-sided

compartments called

ommatidia, anda dorsally

positioned simple eyes calledocelli.


13/37

thorax consists of

three segments

the prothorax(front),

the mesothorax(middle) and

the metathorax(back). Each of these

segments bears a pairofjointed legs.


14/37

comprising of

five segments.

coxa,

trochanter, femur,

tibia and

tarsus.


15/37

Cursorial adapted for running ex. Ground

beetles and cockroaches

Raptatorial adapted for catching and

holding a prey ex. Preying mantisNatatorial adapted for swimming ex.

Diving bugs and water beetles

Fossorial adapted for digging in soil- mole

crickets Saltatorial adapted for jumping-

grasshoppers


16/37

most insects have twopairs calledfront andhind, except flies anda few other groups,which have only one

pair. CAN BE HARD OR

SOFT

In flies eachmethathoracic wing

has been modified toform a knobbedguiding organ called ahaltere.


17/37

Elytra Hard, sclerotized front wings that serve as protectivecovers for membranous hind wings. Ex. Coleopteran anddermaptera.

Hemelytra front wings that are leathery or parchment-like atthe base and membranous near the tip. Ex. Hemiptera,heteroptera

Tegmina front wings that are completely leathery orparchment like in texture. Ex. Othopthera, blattodea andmantodea

Halteres small, club-like hind wings that serves as gyroscopicstabilizers during flight ex. Diptera.

Fringed wings

slender front and hind wings with long fringesof hair. Ex. Thysanoptera

Hairy wings front and hind wings covered with flattenedsetae (scales) ex. Lepidoptera

Hamuli Tiny hooks on hind wing that hold front and hind wingstogether.


18/37

Least modified of the bodyregions may have as manyas 11 segments.

Male cicadas haveappendages called timbalson their abdomen used forsound production

Abdominal Appendages ofAdult Insects The abdomen is made up of

several, more or less similarsegments and often bears apair of jointed, terminalappendages called thecercus.

Cercus(pl. cerci)


19/37

Phytophagous

zoophagous

saprophagous


20/37

Life cycle Involves:1. Reproduction and

embryonic

development

2. Postembryonicgrowth and

development

3. Maturity.


21/37

Female genitalia is called ovipositor. parthenogenesis- capable of giving

birth to viable offfspring with-out

ouside donation of sperms. Aphids

(homoptera) Paedogenesis which refers to

reproduction by the juvenile form,

common to insect with very short life

cycle.


22/37

Egg hatching

The hatching process often begins when the

embryo in the egg swallows fluid or air.

Then the embryo must rupture the egg covering

to escape.

Ruptures may be caused when the insect

produces rhythmic muscular activity and presses

or strike against the covering with its head.

eclosion. Refers to the act of leaving an eggor pupa or emergence of a morph.


23/37

Eggs are laid to where larva can be assured

of food

E.x, dung, water

A fly can lay a thousand egg in a week


24/37

scientific term for the young of any insects

that undergo a complete metamorphosis in

the course of development into adults

Most nutritious/voracious stage of an insect Grubs- beetles

catterpillar-lepidoptera

Maggots- flies

Nymph- young that resembles the adult stage

Naiad- aquatic nymph


25/37

Apoduos-legless, often maggot-like larvae

Campodeiform- elongated,dorsoventrally flattened larvaewith well develop antennaeand thoracic legs

Eruciform - often caterpillar-

like larvae with a more-or-lesscylindrical body, well-developed thoracic legs andhump-like (or more obvious)false legs (prolegs orpseudopods) on the abdomen;

Scarabaeiform- larvae with athick, fleshy (often c-shaped)body well developed heads andthoracic legs but no abdominalpro-legs


26/37

Non-feeding largely

immobile stage.

The pupal stage of

butterfly and moth isknown as Chrysalis.

The protective case

for a pupa is called a

cocoon which is madeup of silk.

Types of:a. Exarate

b. obtect


27/37

Oviparity - In most insects, life begins as an

independent egg. This type of reproduction is

known as oviparity.

Embryogenesis is the developmental processthat usually begins once the egg has been

fertilized. It involves multiplication of cells

(by mitosis) and their subsequent growth,

movement, and differentiation into alltissues and organs of a living insect.


28/37

MORPHOGENESIS

Collectively, all changes that involve growth,

molting, and maturation

METAMORPHOSIS

The marked change in appearance or character

Dependent to the nature of insects life cycle.

Each time an insects molts, it gets a little larger.

It may also change physically in other ways

depending on its type of metamorphosis:

ametabola,

hemimetabola

holometabola.


29/37

Ametabola- youngsare physically similarto adults.

Hemimetabola-

youngs are callednymphs and ifaquatic, naiads.(grasshopper)

Holometabola- clear

distinction existsbetween stages.Completemetamorphosis


30/37

diurnal insects areactive duringdaylight hours

nocturnal insect are

active at nightCrepuscular insect

are active at dawnand dusk

Matinal behavioroccurs only near dawn

Vespertine behavioroccurs only near dusk


31/37

1. Coptotermis sp.- causes damage by eating the

root system of A. mangium saplings as

recorded in Indonesia

2. Zeuzera coffeae- a moth (caterpillar) commonly

known as red borer reportedly attacks Ochroma

pyramidale.

3.Xystrocera festiva- a coleopteran species

damaging Falcata that lay eggs on bark fissures

and larvae initially feed underneath the bark .

4. Hypsipyla robusta- a lepidopteran shoot-borer.

Its larvae bore into the growing shoot and

destroyd the terminal bud.


32/37

Hyblaea puera- commonly known as teak

defoliator

Eutectona machaerales- commonly known as

skelelonizer that attacks teak. Thislepidopteran feeds on leaves leaving major

veins intact

Prionoxytus sp.- a moth, larva bores into the

stem of saplings, feeds within and weakensthe tree.


33/37

Varicose borer Agrilus spp. Bagras

Bark beetle engraver Ips calligraphus

Bagras Pine shoot moth Dioryctria rubella

Benguet Pine and Caribbean Pine

Tip moth Petrova cristata Benguet Pine

and Caribbean Pine

Jumping lice( Psyllids ) Heteropsylla cubana

Ipil-ipil


34/37

A Holistic approach in

Insect and Pest

Management:

- Meets the objective ofForest Entomology.

Yes to

IPM!


35/37

Cultural factors approach

1. Diversity

2. Nutrition

3. Pruning4. Cultivars

5. Location

6. Alternate hosts


36/37

Biological factors

1. Natural enemies

2. Beneficial insects

3. Natural chemicals


37/37

Chemical control- use of selective chemicals

must be practice.

Timing of sprays

Application techniques

Documents

Entom Presentation