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Application of classical biocontrol

 

Introduction of new agents

 

Monitoring and Evaluation

 

 

Successes and Failures

 

Selected Publications

Tools for pre-release assessment of biocontrol agents

 

International Organisation for Biological Control

 

Biological Control of Insects

 

Biological Control of Weeds

Successes and Failures

Worldwide, there are many examples of successful classical biocontrol of pests. The first and most famous was the introduction of the Australian ladybird Cryptolaemus montrouzieri into California to control the cottony cushion scale Icerya purchasi. Other more recent examples are:

• the control of the cassava mealybug in Africa with an encyrtid wasp from South America;
• the control of the cassava mite also in Africa with a predatory mite;
• in Queensland, the control of various citrus scales with hymenopterous parasites from China and elsewhere;
• the control of spiralling whitefly Aleurodicus dispersus by the aphelinid parasitoid Encarsia haitiensis in several tropical and sub-tropical countries;
• with weeds, control of the water weeds salvinia with the weevil Cyrtobagous salviniae, and of water hyacinth with the weevils Neochetina eichhorniae and N. bruchii.

Failures have also been numerous:

• attempts to control the mahogany shoot-borer world-wide have failed. This pest prevents use of the valuable mahogany and red cedar trees in plantations, as the young trees are damaged and their timber becomes worthless.
• control of the western flower thrip in Australia has been unsuccessful to date.
• with weeds, biocontrol of lantana has been a success in Hawaii and some Pacific islands, but is a failure in many other countries including Australia.

Overall, the benefits from the successes far outweighs the money lost on the failures. Successes not only bring economic benefits, in money saved and increased production, but also save the environment from all the chemicals that are otherwise sprayed onto the crops. The health of farmers and their families also benefits, as successful biocontrol reduces their exposure to harmful chemicals.