PRELIMINARY ON CASE STUDY ON THE MASS REARING OF THE
UNIDENTIFIED PARASITOID OF THE COCONUT INSECT SCIENTIFIC NAME (HEMIPTERA:
DIASPIDIDAE)
By.
ABSDAMAHAN’SLIVE-STREAM NEWS TV/ June 17, 2014) Public Hearing on case
study at Session Hall General Santos City. On their 46th Regular
Session Sangguniang Panglungsod.
Researchers: V.C. Gallego, C.E., Gallego and L.S. Doronio,
SRS II and Scientist I, Division Chief III and Laboratory Aide. Crop Protection
Division, Davao Research Center, Philippine Coconut Authority (PCA)
Case Study
ABSTRACT
An unidentified parasitoid attacking coconut scale insect
(CSI), Aspidiotus sp. was discovered after series of intensive field survey and
collection in Davao region. The said wasp was suspected to be genus of Aphytis
and observed to be a potential biological control agent of the pest.
Initial results on its biology and behavior under laboratory
condition and their efficiency in the field were conducted at PCA-Davao
Research Center. Successful mass production protocol of the parasitoid in the
laboratory was developed. The technique involves rearing of coconut scale
insect on the squash fruits as host of the parasitoid. This method is currently
being used to produce considerable number of parasitoids for field release in
scale insect-infested areas.
A satellite laboratory for the mass propagation of the
parasitoid was established in Isabela City, Basilan for the control of coconut
scale insect (CSI) infestation in the island. A large mass production laboratory
is being proposed in Batangas and Laguna where heavy CSI infestation was found.
IMPORTANCE
·
Aspidiotus sp. Are tiny sucking insects found
attached and fed on the underside of coconut leaves; and also found on the
nuts.
·
In advance cases: affected leaflets may dry out
due to sap loss, wilting of fronds and finally wither, premature nut-fall,
significant yield reduction and death of the palm.
·
The initial outbreak of the pest was reported in
Tanauan, Batangas in 2010 and spreading to adjacent areas in Southern Luzon.
·
Two years after, the coconut trees in the Island
of Basilan was infested by the same pest.
·
PCA already implemented control strategies such
as leaf pruning of infested leaves/fronds, fertilizer application, spraying
with cochin oil, insecticide spraying and release of predatory coccinellid
beetles.
ACTIVITIES
A.
Explore mass rearing technques
B.
Conduct initial biological studies (life cycle,
fecundity, longevity)
C.
Conduct hands-on training on the mass production
of the parasitoids
SALIENT ACCOMPLISHMENTS
A.
Rearing of the host coconut scale insect
1. Secure clean mature squash fruits and CSI infested leaves
2. Allow CSI crawlers to transfer onto squash fruits.
3. Once CSI are established, keep squash in individual rearing tray until
crawlers developed into 2nd instars for parasitization process.
4. Prepare as many infested squash in larger plastic trays for the
introduction of the parasitoids.
B. Rearing the Unidentified Parasitoid
1. Healthy
and parasitized CSI on squash place together in larger rearing tray for
parasitization.
2. After
one week, remove the introduced squash (la) from the rearing tray and transfer
to another tray for parasitoid emergence.
3.Replace
or introduce another healthy 2nd instar CSI on squash ( same as la )
for parasitization.
4. Repeat
the procedures from 1 to 3 for continuous mass production of the unidentified
parasitoid. Make sure there are still emerging adult parasitoids from the
parasitized CSI ( 1b )
5. The parasitized CSI on the squash ( at
least 15 day old from exposure ) are now ready for field release.
C. Method of Release in the
Field
1. Release two pieces of squash with
paralyzed CSI per hectare. Allow emerging parasitoids to fly freely and find
its host. Repeat field releases monthly once stocks are available.
Initial studies on the biology,
emergence and efficiency of the unidentified CSI parasitoid
·
Total developmental period. 17.67 days ( from
egg to adult emergence ).
·
One mated female parasitoid can produced an ave.
of 6.53 wasps.
·
Adult longevity can be enhanced to 3.07 days
when fed with honey.
·
Emergence of the parasitoids is ver pronounce in
the morning with 81.17% emergence.
·
Initial observation on the field efficiency of
the parasitoid revealed 29.88% parasitism.
IMPLICATIONS AND RECOMMENDATION
·
The unidentified parasitoid suspected to the Aphytis
sp. Can be a potential biological control agent against the coconut scale
insect.
·
Biological control using this parasitoid can be
a long term control strategy for the CSI to reduce its population into a
manageable level.
·
Therefore, to produce considerable number of the
parasitoids for the field release, a large mass production laboratory should be
established in the CSI outbreak areas.