Taro beetle is a serious pest of dalo in Fiji and other Pacific countries where it is found. It is a direct threat to Fiji’s multi-million dollar taro exporting industry to New Zealand and Australia. It poses a serious threat to Pacific neighbours where the beetle is not present and taro is the major cash crop.

In Fiji the beetle is not found in the two main taro growing regions of Savusavu and the island of Taveuni, in the Northern Group. However, it is widespread along the east coast of the main island of Viti Levu including the outer islands of Ovalau and Levuka.

All movement of dalo from Viti Levu and Ovalau to the outer islands and the island of Rotuma are strictly prohibited.

The pest lives in the soil and burrows inside the taro corm leaving behind a maze of tunnels. Beetle-damaged taro cannot be exported or sold to local supermarkets. Badly damaged taro cannot even be used for home cooking. The corm begins to rot soon after beetle damage.

In Fiji taro beetle damage accounts anywhere from 4 to 25 percent of total taro crop. To smallholder farmers this is a big chunk of their livelihood taken away.

Identifying the best combination of practises to combat taro beetle is the objective of the regional Taro Beetle Management (TBM) project. The project is an initiative of SPC Plant Protection Service and the Technical Coordinators of the project met in Nadi end of May to review work progress and plan further work. 

TBM was Initially funded by EU under the Pacific Regional Agricultural Development Project (PRAP). In 2002 the Australian Centre for International Agricultural Research (ACIAR) began funding the project. However, the project is now extended to other Pacific islands affected by the beetle. The extension is made possible with funding assistance from the European Union (EU). The new countries now include Kiribati and Vanuatu. 

EU and ACIAR are now co-funding the Taro Beetle Management project. The project is coordinated by Sada Nand Lal, Entomologist with SPC Plant Protection Service.

Roy Masamdu, Principal Entomologist for PNG’s National Agricultural Research Institute (NARI) supervises TBM activities in PNG. Mr. Masamdu says, in PNG, the beetle is a pest to 15 economic plant species including taro. He says the main control method now tested in PNG is a natural enemy of the beetle and is not a chemical-based pesticide. It is a fungus that occurs naturally in the soil called Metarhizium. The fungus grows on and kills the beetle. Present trials will find out how much of the fungus can be applied per plant to reduce beetle damage. This is a promising and sustainable method of taro beetle management. 

EU encourages projects that identify and use natural enemies of pests or biological control, which are much safer to the environment. 

Similar fungal trials and chemical screening are being conducted in Fiji with the first trials to be analysed in June 2003. Under a previous regional insecticide-screening project, no conclusive results were obtained. The main objective of the current trial is to identify a selective insecticide effective against taro beetle. 

Mr. Moti Lal, Principal Research Officer at Koronivia Research Station, supervise activities for the taro beetle project in Fiji. Beetle-ravaged Navua, in eastern Viti Levu, is the site of the chemical evaluation trials now underway. Residue analysis is part of the chemical trials where corms will be tested for the presence of insectides. Fiji will also be testing the Metarhizium fungus, where the beetle isn’t as complex as in PNG.

In Vanuatu there are five known taro beetle species and taro beetle is a major constraint to taro production. The plan is to compare biological and chemical control trials.

In Kiribati only one known species of the beetle is found and is confined only on the main island of Tarawa. The beetle was introduced some 60 years ago. 

The occurrence in the soil of the Metarhizium fungus is the main constraint to using this natural enemy of the beetle. Attempts to mass produce the fungus in the tropics is now being looked at with assistance provided by Dr. Richard Milner formerly of CSIRO but now a private consultant to the taro beetle project. Dr. Milner is supplying the Metarhizium fungus from Australia. He travelled earlier in the year to assess the natural occurrence of the fungus in Kiribati. He found very little beetle activity in Tarawa. However, soil samples extracted and sent to Australia for analysis confirmed the presence of the fungus in atoll soils.

In the absence of any immediate recommended measures to eradicate taro beetle farmers in Fiji are targets of public education messages urging them not to move planting material from affected areas. This measure is to quarantine the pest and to prevent it from spreading to new areas. 

SPC Plant Protection Service and Fiji Ministry of Agriculture, Sugar and Land Resettlement (MASLR) technical and extension staff held farmer field days and disseminated extension materials as public awareness to show damages to taro caused by the beetle and to emphasise to farmers not to move out any taro planting materials from affected areas.

Similarly Pacific island countries where the beetle is not found should enforce strict quarantine measures at their national borders to prevent any introduction of taro planting material from countries where the beetle is found.

Banana is another host for the beetle and likewise national quarantine services should strictly prohibit the importation of banana-related planting material.

SPC Plant Protection Service, through EU and Australia funding, is providing the technical expertise and administrative support for the regional project. The development of an environmentally sustainable biological control system for taro beetle is the goal of the project.