| Affiliation: | (1) Insect Biocontrol Laboratory, Department of Entomology and Nematology, National Agricultural Research Center, Kannon-dai 3-1-1, Tsukuba Ibaraki, 305-8666, Japan;(2) Center of Ecological Research, Kyoto University, Otsu Shiga, 520-2113, Japan;(3) CREST of Japan Science and Technology Cooperation, Tokyo 102-8666, Japan;(4) Fragrance Laboratory, Soda Aromatic Co. Ltd., Tokyo 103-0023, Japan;(5) Present address: National Agricultural Research, for Western Region, Fukuyama Hiroshima, 721-8514, Japan |
| Abstract: | 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. Thex andy displacements are registeredusing 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 adultPhytoseivlus 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. |
