Infochemical-mediated intraguild interactions among three predatory mites on cassava plants

Area of Science:

• Ecology
• Behavioral Ecology
• Chemical Ecology

Background:

• Carnivorous arthropods face challenges balancing foraging and predator avoidance, especially with limited prey.
• Understanding predator interactions is vital for ecological dynamics, particularly in resource-scarce environments.

Purpose of the Study:

• To investigate how volatile chemicals from prey patches, influenced by the presence of conspecific or heterospecific predators, shape predator guild structure.
• To determine if predatory mites can use olfactory cues to assess prey patch profitability and avoid competitors.

Main Methods:

• An olfactometer was used to test the responses of three predatory mite species (Typhlodromalus manihoti, T. aripo, and Euseius fustis) to odours from prey (Mononychellus tanajoa)-infested cassava leaves.
• The odour sources included prey alone or prey with conspecific or heterospecific predators.

Main Results:

• All three predatory mite species avoided odour sources associated with the presence of other predatory mites (conspecifics or heterospecifics).
• Typhlodromalus manihoti demonstrated the ability to discriminate between conspecific and heterospecific predator odours, showing a preference for patches with T. aripo over T. manihoti.
• The findings indicate that predatory mites can assess prey patch profitability using volatile cues.

Conclusions:

• Volatile chemicals from prey patches containing competitors significantly influence the behavior of predatory mites.
• Interspecific and intraspecific interactions mediated by olfactory cues play a substantial role in structuring predator guilds and affect population dynamics.
• These behaviors are particularly important under conditions of low prey availability, impacting both predator and prey populations.