Báo cáo nghiên cứu khoa học " CITRUS INSECT PEST AND THEICITRUS INSECT PEST AND THEIR NATURAL ENEMIES " docx

CITRUS INSECT PEST AND THEIR
CITRUS INSECT PEST AND THEIR
NATURAL ENEMIES
NATURAL ENEMIES
Ho
Ho
à
à
Vaên
Vaên
Chie
Chie
á
á
n
n
,
,
Leâ Quo
Leâ Quo
á
á
c C
c C
ö
ö
ô
ô
ø
ø
ng

ng
,
,
Laâm Th
Laâm Th
ị
ị
M
M
ỹ
ỹ
Nương
Nương
Southern Regional Plant Protection
Southern Regional Plant Protection
Compiling based on Citrus pests and their natural enemies
Compiling based on Citrus pests and their natural enemies
-
-
Integrated pest
Integrated pest
management in Australia edited by Dan Smith, GAC Beattie & Roger
management in Australia edited by Dan Smith, GAC Beattie & Roger
Broadley
Broadley
Leafminer
(Phyllocnistis citrella Stainton)


1) symptom

1) symptom
Leafminer
(Phyllocnistis citrella Stainton)
Leafminer
•Adult
Leafminer
Egg and larva
Leafminer
Pupa
Pupa
Life Cycle
Adult
First instar
Second instar
Third instar
Pupa
Pre-pupa
Pupa in pupal chamber
Eggs
Leafminer
(Phyllocnistis citrella Stainton)
Leafminer
Leafminer
usually occur in the early rain season
usually occur in the early rain season
and young shoot stage.
and young shoot stage.
2). Life cycle
2). Life cycle



The complete life cycle takes 14
The complete life cycle takes 14
-
-
17 days or
17 days or
times longer.
times longer.


Most adults live for less than a week, female
Most adults live for less than a week, female
moths start laying eggs about 24 hours after
moths start laying eggs about 24 hours after
mating.
mating.
Leafminer
(Phyllocnistis citrella Stainton)
Life cycle
Life cycle


Eggs are laid at night, a female can laid more than
Eggs are laid at night, a female can laid more than
50 eggs their life (as many as 20 eggs per night).
50 eggs their life (as many as 20 eggs per night).


The flat, slightly oval eggs are about 0.3 mm long

The flat, slightly oval eggs are about 0.3 mm long
and look like tiny water droplets on the leaves. Eggs
and look like tiny water droplets on the leaves. Eggs
are deposited singly, on the undersides of leaves
are deposited singly, on the undersides of leaves
near the midrib, usually at the base of the leaf.
near the midrib, usually at the base of the leaf.
Young leaves 10
Young leaves 10
-
-
20 mm in length are preferred sites
20 mm in length are preferred sites
for egg laying.
for egg laying.
Leafminer
(Phyllocnistis citrella Stainton)


Hatching can occur within a day, and the young larva
Hatching can occur within a day, and the young larva
immediately burrows under the leaf surface.
immediately burrows under the leaf surface.


Each pale
Each pale
-
-
green larva tunnels a characteristic, sinuous,

green larva tunnels a characteristic, sinuous,
silvery mine in the leaf, with a raised parchment
silvery mine in the leaf, with a raised parchment
-
-
like skin
like skin
lined centrally with dark excreta. Larva never leave their
lined centrally with dark excreta. Larva never leave their
mines to form other mines or move between lower and
mines to form other mines or move between lower and
upper sides of leaves. Damage is caused by the larvae as
upper sides of leaves. Damage is caused by the larvae as
they mine immature foliage. Twisted and curled leaves are
they mine immature foliage. Twisted and curled leaves are
generally the first symptom noticed.
generally the first symptom noticed.


Larva stage is about 5
Larva stage is about 5
-
-
6 days. The pre
6 days. The pre
-
-
pupa and pupa are
pupa and pupa are
about 6 days and then adults emerge.

about 6 days and then adults emerge.
The leaves growth stages and their symptom
The leaves growth stages and their symptom
Aphids
Aphids
(
(
Toxoptera
Toxoptera
sp.)
sp.)
1) Symptom
1) Symptom
Aphids
Aphids
(
(
Toxoptera
Toxoptera
aurantii
aurantii
Boyer de
Boyer de
Fonscolombe
Fonscolombe
)
)


Aphids are dark brown or black and about 2 mm long.

Aphids are dark brown or black and about 2 mm long.
They live on the young leaves and shoots with high
They live on the young leaves and shoots with high
density They feed on plant sap, using their sucking
density They feed on plant sap, using their sucking
mouthparts. They produce a sugary liquid (honeydew), on
mouthparts. They produce a sugary liquid (honeydew), on
which sooty mould grows, and can transmit plant viruses.
which sooty mould grows, and can transmit plant viruses.


Aphids may be winged or wingless, depending on the
Aphids may be winged or wingless, depending on the
state of their food supply and their density
state of their food supply and their density


Damage: deformation, flower drop, sooty mould, reduced
Damage: deformation, flower drop, sooty mould, reduced
fruit set, distortion of young leaves and shoots.
fruit set, distortion of young leaves and shoots.
Aphids
Aphids
2). Life cycle
2). Life cycle
There are probably
There are probably
25
25
-

-
30 generations
30 generations
per years.
per years.
The most important
The most important
known of vectors
known of vectors
tristeza
tristeza
virus to
virus to
citrus plant. It is
citrus plant. It is
very dangerous for
very dangerous for
citrus grower
citrus grower
nymph
wingless
Adult
winged
Adult
Whitefly
Whitefly
(
(
Aleurodicus
Aleurodicus

dispersus
dispersus
)
)


1). Symptom
1). Symptom
Whitefly
Whitefly
(
(
Aleurodicus
Aleurodicus
dispersus
dispersus
)
)


Citrus whitefly usually occur on undersides of
Citrus whitefly usually occur on undersides of
young leaves , they are 2.5 mm long, with white
young leaves , they are 2.5 mm long, with white
powdery wings. Adult look like small moths,
powdery wings. Adult look like small moths,
they are related to scale insect.
they are related to scale insect.



Adult will fly out in swarms if foliage is
Adult will fly out in swarms if foliage is
disturbed.
disturbed.


The eggs are yellow and oval
The eggs are yellow and oval
-
-
shaped with
shaped with
white powdery wax, underside the young
white powdery wax, underside the young
leaves or fruits, and circular egg laying pattern .
leaves or fruits, and circular egg laying pattern .
Whitefly
Whitefly
(
(
Aleurodicus
Aleurodicus
dispersus
dispersus
)
)
2). Life cycle
2). Life cycle



The larvae settle in group on the underside of
The larvae settle in group on the underside of
leaves . At first they are flat and resemble scale
leaves . At first they are flat and resemble scale
crawlers feeding and developing beneath a
crawlers feeding and developing beneath a
protective waxy covering. Both adults and nymphs
protective waxy covering. Both adults and nymphs
produce sticky honeydew on which sooty mould
produce sticky honeydew on which sooty mould
grows, and transmitting virus diseases.
grows, and transmitting virus diseases.


Three growth stages are followed by a pupa and
Three growth stages are followed by a pupa and
then winged adult. The pupae are often found on
then winged adult. The pupae are often found on
leaf midribs and look like young soft brown scale.
leaf midribs and look like young soft brown scale.
There are at least 5 to 6 generations per year.
There are at least 5 to 6 generations per year.
Whitefly
Whitefly
Citrus Hopper
Citrus Hopper
(
(
Colgar
Colgar

peracutum
peracutum
Walker)
Walker)
Citrus Hopper
Citrus Hopper
(
(
Colgar
Colgar
peracutum
peracutum
Walker)
Walker)
1). Shape and habits
1). Shape and habits


Citrus Hopper
Citrus Hopper
is about 10 mm long. When at rest their
is about 10 mm long. When at rest their
wings are tent
wings are tent
-
-
like shape.
like shape.
Citrus Hopper
Citrus Hopper

can occur on
can occur on
mango also;
mango also;


They are pale green to white, with small red spot in the
They are pale green to white, with small red spot in the
middle of each forewing, and usually a red border on the
middle of each forewing, and usually a red border on the
forewings.
forewings.
Citrus Hopper are usually green, and covered with
Citrus Hopper are usually green, and covered with
small yellow spots
small yellow spots
. Both adult and larvae are mobile,
. Both adult and larvae are mobile,
skipping short distances when disturbed. Adult are weak
skipping short distances when disturbed. Adult are weak
fliers
fliers
Citrus Hopper
Citrus Hopper
(
(
Colgar
Colgar
peracutum
peracutum

Walker)
Walker)
2). Life cycle
2). Life cycle


The eggs of species are laid in oval shaped
The eggs of species are laid in oval shaped
masses about 50 eggs. The eggs masses are
masses about 50 eggs. The eggs masses are
about 5 mm in diameter. At first eggs are
about 5 mm in diameter. At first eggs are
white, but they darken near hatching.
white, but they darken near hatching.


Four growth stages are followed by adult.
Four growth stages are followed by adult.
The complete life cycle takes 1 to 2 months
The complete life cycle takes 1 to 2 months
There are about 3 to 6 generations per year.
There are about 3 to 6 generations per year.
Citrus Hopper
Citrus Hopper
2). Life cycle
2). Life cycle
Spined
Spined
citrus bug
citrus bug

(
(
Rhynochocoris
Rhynochocoris
poseidon
poseidon
Kirkaldy
Kirkaldy
)
)
1). Shape and damage symptoms
1). Shape and damage symptoms
The
The
spined
spined
citrus bug 15
citrus bug 15
-
-
20 mm long with a
20 mm long with a
prominent spine on each shoulder of the
prominent spine on each shoulder of the
thorax. Both nymphs and adults of plant
thorax. Both nymphs and adults of plant
-
-
feeding species cause plant and fruit damage
feeding species cause plant and fruit damage

with their sucking mouthparts. The bug pierce
with their sucking mouthparts. The bug pierce
the rind of fruit at any stage causing drying
the rind of fruit at any stage causing drying
and brown staining of segments, gumming and
and brown staining of segments, gumming and
fruit drop. In ripe fruit, damage is often not
fruit drop. In ripe fruit, damage is often not
evident until the fruit is cut open. Young fruit
evident until the fruit is cut open. Young fruit
fall readily after attack. They can cause total
fall readily after attack. They can cause total
crop loss
crop loss
Spined
Spined
citrus bug
citrus bug
(
(
Rhynochocoris
Rhynochocoris
poseidon
poseidon
Kirkaldy
Kirkaldy
)
)
Damage symptoms
Damage symptoms

Spined
Spined
citrus bug
citrus bug
(
(
Rhynochocoris
Rhynochocoris
poseidon
poseidon
Kirkaldy
Kirkaldy
)
)
2). Life cycle
2). Life cycle