Cocoa pod borer scoping study in PNG

Papua New Guinea

Dr Wai Hong Loke
Phone: 60 3 89432921
Fax: 60 3 89426490
Email: loke@cabi.org

$65,000

01/06/2006 - 31/10/2006

Dr T K Lim

The Asian cocoa pod borer (CPB), Conopomorpha cramerella, is a devastating moth pest of cocoa and the most serious constraint to cocoa production in Southeast Asia's cocoa-growing countries. Incursion of this pest into PNG was detected at Keravat, East New Britain Province (ENBP) in March 2006, with severe damage observed (90 to 100%) in some areas around the Lowlands Agricultural Experiment Station (LAES) and Kareeba Plantation. Cocoa production in PNG is an important activity (economically, socially and environmentally) and a prime pillar of the national economy. There have been both successes and failures in eradication of CPB pest incursions. Experience in the Philippines, Malaysia and Indonesia highlight that total and permanent eradication is very difficult to achieve.
CABI personnel have relevant technical expertise and a long, historical and significant track record of managing agricultural invasive alien species (IAS) such as the CPB in cocoa. A CABI team was engaged to visit PNG to assist and further build upon the initial efforts to ascertain potential for eradication and plan future contingency/management programs.

The CABI team visited PNG from 7 to 21 August 2006 to support the management of the cocoa pod borer incursion. The team worked closely with PNG agencies, ACIAR, CCI, NAQIA, NARI and others. At the NARI National Agriculture Entomology Collection Centre records were found that substantiated reports of the presence of CPB in PNG from the 1940s to the 1960s. The reason why CPB was not subsequently reported until 2006 remains unclear.
CPB was confirmed in cocoa of ENBP on 29 March 2006 and West Sepik in June. Eradication operations were carried out over a 2000-ha zone of cocoa at ENBP, with follow up in West Sepik. Eradication procedures at ENBP were deemed exemplary, with inputs generally equalling if not exceeding those practised in similar efforts of other countries. There were, however great contrasts between conditions at ENBP and West Sepik (which suffered from poor access and communications, isolation, discontinuous locations and relative neglect of cocoa plantings) and it will be a major challenge to fulfil all that has been planned for West Sepik.
In the light of the overall impressions gained through the visit, prognoses for eradication of CPB depend on three scenarios under which cocoa are grown. Prospects for eradication diminish down the continuum from Scenario 1 to 3. In a best-case situation, the CPB would be eradicated in the ENBP while incursions in West Sepik would be contained. This could lead eventually to the division of PNG into CPB-free zones, with strict inter- and intra-country quarantine measures to maintain the status of such zones. The worst-case scenario would be the failure to eradicate the CPB, leaving the cocoa enterprises of the nation trying to live with and manage the pest. Arrival at the latter situation is strongly indicated should the CPB re-emerge at the Scenario 1 infestations, despite the current intense eradication inputs.
The CABI team recommended immediate implementation of follow-up actions outlined in the report by the Emergency Response Unit at ENBP. Of these, the following were emphasised:
Maintenance of CPB awareness and education;
Institution of a systematic and standardised nation-wide surveillance program.
Surveillance must be multi-tactical in nature.
At West Sepik, urgent requirements were:
Improve accessibility and communications for emergency response work;
Increase awareness of the pest among farmers and the general populace of the Province.
Implement multi-tactical surveillance for the pest.
Set up quarantine road blocks.
Although it is only logical for authorities to attempt to eradicate CPB incursions in PNG, the possibility of this being fully realised in the long term is unlikely. It would thus be prudent to make plans in PNG for managing the pest in its cocoa. Recommended priorities for the management of CPB infestations were:
Maintenance pruning, canopy reduction and height control of cocoa;
Regular and systematic monitoring;
Frequent and complete harvesting;
Sanitation;
Target pod spraying;
Use of tolerant/resistant planting materials.
There is a concern that even implementing the above basic inputs would not be feasible on the more remote or highly subsistence-level farms. However inputs (i), (iii) and (iv) alone could bring about meaningful suppression of CPB damage. Effective farmer training is needed through participatory activities, and this can only be implemented after training of extension workers. This process would require the following:
Begin by training and nurturing a core group of Master Trainers/Facilitators.
The Master Trainers/Facilitators would then train many more Trainers (or Facilitators).
The Facilitators would then conduct farmer training (with 1-2 Facilitators training a group of 30-35 farmers each time).
The project team believed there was merit in developing a curriculum and trial implementation of such a program in preparation for possible establishment of CPB in PNG.
The following directions for research were recommended:
Use tolerant/resistant planting materials.
Refine CPB monitoring methods.
Prospect for biological control agents.
Screen for insecticides and pesticide application technology.
Install demonstration plots.
More basic and long-term research of benefit to managing CPB in PNG includes identification of alternative host plants of CPB, molecular determination of CPB biotypes or races together with cross-hybridisation and cross-infestation studies, classical biological control by importation and mass production of parasitoids, development of biopesticides, and investigations on other semiochemicals besides pheromones.