PRELIMINARY ON CASE STUDY ON THE MASS REARING OF THE UNIDENTIFIED PARASITOID OF THE COCONUT INSECT SCIENTIFIC NAME (HEMIPTERA: DIASPIDIDAE)

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 46^th 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 2^nd 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 2^nd 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.