State-dependent and odor-mediated anemotactic responses of a micro-arthropod on a novel type of locomotion compensator.
A novel type of locomotion compensator was designed and tested for its use in orientation behavior experiments with a predatory mite. In this apparatus, displacements of the test animal in the two-dimensional plane are recorded using video equipment and a servosphere that keeps the animal in focus. The x and y displacements are registered using two rotation encoders and are compensated using a pair of servo-motors, in such a way that the animal is always positioned on top of the sphere, yet moves freely. Well-fed and starved predators were tested for their responses to (1) still air, (2) a stimulus-free air flow, (3) an air flow with odors from uninfested Lima bean leaves, and (4) an air flow with odors from Lima bean leaves infested by plant-feeding mites, the prey of the predatory mites. Anemotactic responses of adult Phytoseiulus persimilis females were feeding state dependent. Well-fed predators moved downwind under Treatments 1-3 but moved neither up- nor downwind in the presence of odors from infested plants (Treatment 4). Starved predators moved upwind under all treatments. These results are in agreement with those of earlier studies in a wind tunnel, and therefore, the new type of locomotion compensator (LC-100) offers an excellent method for studying the orientation behavior of micro-arthropods.
Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands. tilborg@science.uva.nl
Merijn
M
van Tilborg
Jan N C
JN
van der Pers
Peter
P
Roessingh
Maurice W
MW
Sabelis
D000818:Animals; D002633:Chemotaxis / Q000502:physiology*; D003625:Data Collection / Q000295:instrumentation / Q000379:methods; D008124:Locomotion / Q000502:physiology*; D008925:Mites / Q000502:physiology*; D009812:Odorants; D009949:Orientation / Q000502:physiology; D013268:Stimulation, Chemical