Using biocontrol agents to control invasive species

What is Biological control?

Biological control is the introduction of the plant’s natural enemies to its new habitat, so that these natural enemies will remove the plant’s competitive advantage. 

In the control of invasive plants, the commonly used biocontrol agents are insects, mites and pathogens (disease-causing organisms such as fungi). These agents will damage the targeted plant by feeding on the stem, root, leaves or flowers of the plants.

History of biological control

South Africa has a long history of biological control of weeds, which began in 1913 with the highly-successful introduction of a cochineal insect against a prickly pear cactus (Opuntia monacantha). Over the succeeding 100 years of biological control use at least 73 plant species have been targets for biological control. Agents have become established on 48 of the targeted species and South Africa remains committed to expanding this area of research.