What pest control technique involves the human manipulation or introduction of parasites, predators, or pathogens?

The principle behind biological control techniques is to use natural enemies to manage pest populations. This involves the intentional introduction or enhancement of organisms such as parasites, predators, or pathogens that target specific pests. For example, lady beetles may be released to control aphid populations, or beneficial nematodes may be introduced to manage soil-dwelling insect larvae. This method not only aims at reducing pest numbers but also seeks to establish a more balanced ecosystem by leveraging natural processes.

In contrast, chemical control techniques refer to the application of synthetic or natural chemicals to combat pests, which doesn't involve the introduction of other organisms. Cultural control techniques focus on practices that optimize plant health and reduce pest establishment through environmental manipulation, such as crop rotation, rather than biological interactions. Mechanical control techniques involve the use of physical methods such as traps or barriers to directly reduce pest populations, again not utilizing biological organisms in the process. Thus, the unique characteristic of biological control techniques is their reliance on natural biological phenomena for pest management.