The adult female fly feeds up to a week on 
protein, e.g. on bacteria growing on plant 
surfaces, and on sugars, e.g. in honeydew 
and nectar, before laying eggs.
 Eggs are white, banana-shaped and 1 mm 
long. They are deposited in batches of 10-12 into the spongy  albedo of the fruit. The 
rind puncture is not visible at first, but 
later a yellow area develops around 
the‘sting’site.
                
              
                                            
                                
            
                       
            
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Fruit fly
(Bactrocera dorsalis)
2). Life cycle 
 The adult female fly feeds up to a week on 
protein, e.g. on bacteria growing on plant 
surfaces, and on sugars, e.g. in honeydew 
and nectar, before laying eggs.
 Eggs are white, banana-shaped and 1 mm 
long. They are deposited in batches of 10-
12 into the spongy albedo of the fruit. The 
rind puncture is not visible at first, but 
later a yellow area develops around 
the‘sting’site. 
Fruit fly
(Bactrocera dorsalis)
2) Life cycle 
 Eggs hatch in 2-3 days and the larvae borrow 
into the fruit pulp. The number of larvae per 
fruit varies from one to 12 or more. Larvae 
complete their development in about 10 
days. They then drop to the ground to fined a 
suitable place to pupate. Pupation occurs in 
the soil and can take about 7- 9 days. Pupae 
are brown, barrel-shaped and about 4-5 mm 
long. They are over 6 generations per years.
Fruit fly
2) Life cycle 
egg egg
Life cycle of fruit fly
Mealybug
(Pseudococcus sp.)
 1). Shape 
Mealybugs
(Pseudococcus sp.)
 1). Shape and 
damage 
symptoms
Mealybugs
(Pseudococcus sp.)
 1). Shape and damage symptoms
 There are many species attack on citrus plant. 
Although shape is different, habits and symptoms 
are similar. The adult female mealybug is a slow-
moving, and covered by a thin coating of white, 
mealy wax which extent into filaments around the 
edge of the body.
 Eggs hatching are small one and move flexility. If 
larvae without pupae stage would be adults female 
and vice versa.
Mealybugs
(Pseudococcus sp.)
 1). Shape and damage symptoms
 Adult males are tiny, delicate winged insect with 
long tail filament.
 Juveniles and adults seek out sheltered sites: 
under the fruit calyx, inside the navel of fruit, 
between touching fruit and leaves, in curled 
leaves attacked by citrus leafminer and inside 
cracks and crevices in bark.
 Mealybug excrete sticky honeydew that is good 
medium for the growth of sooty mould and other 
fungi. 
Mealybugs
(Pseudococcus sp.)
2). Life cycle “Citrophilous”
 Citrophilous mealybug female lay about 500 
eggs in a cottony egg sac, and hatch within a 
few days. There are three moults in females 
and four in male.
 The complete life cycle takes about 2 months 
and there are 3-4 generation per years. 
Mealybugs
(Pseudococcus sp.)
2). Life cycle “Citrophilous”
Mites
Panonychus citri
1). Shape and damage symptoms 
 The group mites attack on citrus include 8 
species. However, red mite occur and cause 
damage popular almost citrus garden in 
Mekong delta area.
 The adult female red mite has oval body, and 
is 0,5 mm long. The body is purple-red color 
with long white bristle on the back and sides, 
the pale legs. The adult male is smaller than 
female and legs are longer than one.
Mites
1). Shape and damage symptoms 
 Citrus red mite feeds on citrus fruit, leaves (young and 
old) and green twigs. The maturing leaf is preferred, and 
most damage occurs on the upper surface, makes leaf 
curved, spotted grey scarring of the rind.
Citrus rust mite
(Phyllocoptruta oleivora)
Mites
 1). Rind damage on fruit caused by citrus red mite 
Mites
2). Life cycle 
 The adult female citrus mite lays 20-40 eggs at rate of 2-3 
per day. The egg is bright red and spherical, 0,13 mm 
diameter. Eggs are commonly deposited along the midribs 
of the leaves. Newly hatched larvae are red and have 6 
legs. They develop through two further nymphal stages 
with 8 legs before reaching adulthood. From egg to adult 
can takes about 2-8 weeks depend on temperature and 
humidity, the adult female live about 18 days. There are 
8-10 generations per years. 
Thrips (Thysanoptera)
1). Shape and damage symptoms
 There are 5 species of thrips caused damage on 
Citrus. Thrips are small with two short 
antennae, and rapid moving when disturbed. 
Adult thrips are about 3-4 mm; however, some 
one grow to length of about 12 mm. Wings of 
thrips are narrow with a fringe of long hairs on 
the hind edge, and other are wingless. 
Thrips
1). Shape and damage symptoms
Thrips have mouthparts adapted for sucking and 
rasping. Flowers are often favoured feeding sites, 
but thrips also feed on developing fruit and young 
leaves. Heavy infestations of thrips cause twisting 
and grey scarring of young foliage similar to the 
damage cause by broad mites; ring scarring 
around the stem end of a navel on fruit. 
Thrips
 1). Shape
(Scirtothrips dorsalis Hood)
(Megalurothrips kellyanus)
(Chaetanaphothrips orchidii)
(Heliothrips haemorrhoidalis
Thrips
 1). Damage symptoms
Thrips (Scirtothrips dorsalis Hood)
2). Life cycle
 Thrips often laid into soft tissue on very young 
fruit near the calyx, or in young leaves (near 
the midrib or main vein), eggs are 0.3 mm long. 
Adult female lay about 2-3 eggs a day.
Larvae develop through two stages to become a 
propupa. They complete life cycle takes about 5 
weeks. Thrips adult can live 3 months. There 
are about 6 generations per year 
They can attack many other fruit, beside 
citrus. 
Thrips (Scirtothrips dorsalis Hood)
2). Life cycle 
propupa
Fruitpiercing moths
(Rhytia hypernestra)
Shape and damage symptoms
Fruitpiercing moths
(Rhytia hypernestra)
 Belong to Noctuidae, the adult moths fly 
to orchards during the night to suck juice 
from ripening fruit, and they rest outside 
the orchards by night. Adult fruitpiercing
moths are large and stout-bodied with a 
wingspan of 100 mm. There are many 
species in the Mekong Delta, But the 
yellow-orange, with black patches or spots 
are popular. Larval hosts include native 
vines 
Fruitpiercing moths
(Othreis fullonia (Clerck)
 The larvae feed on native vines for 
about 3 weeks, through 5 stages before 
forming a dark-brown pupa within a 
delicate silk cocoon between webbeb
leaves. After 3 weeks, adults emerge 
from the pupa. Beside citrus the moths 
can attack many other fruit tree. There 
are about 2-4 generations per year. 
Psyllids (Diaphorina citri)
1). Shape and biological characteristic
* Eggs are very small with slight yellow, 
pear shaped. They usually laid on young 
leaves and buds 
* Psyllids larvae are small, oval shaped, new 
hatching with yellow (second and third 
instar) and yellow-brown (fourth and five 
instar), with 2 small wings 
Psyllids (Diaphorina citri)
1). Shape and biological characteristic
Adult: 2.5- 3 mm long; brown dark body, wings 
have light brown color. Head is acute and 
brown color, red eyes.
When they are on the leaf, the body of 
the psyllid will post the angle about 40 0. 
Adult Psyllids are 2,5-3 mm long Eggs
Psyllids (Diaphorina citri)
 Larvae Adult
2. Morphology and Life cycle
 After mating, the Female start laying eggs in the tissue of 
buds, or young shoots which are not yet open. A female 
can lay more than 200 eggs.
 Eggs are yellow, oval shape 0.3 mm long. egg period 2-11 
days.
 After hatching, young nymph can move for some 
distance, and the color of body is yellow or green. The 
nymph has 5 instars to become adult which take 12-22 
days.
 Adult can live 15 –45 days 
 The life cycle of psyllid is about 30-75 days; Average 
about 40 days.
 There are about 12-14 generations per year.