title: Host orientation using volatiles in the phoretic nematode Caenorhabditis japonica.
abstract: Host orientation is the most important step in host-searching nematodes; however, information on direct cues from hosts to evoke this behaviour is limited. Caenorhabditis japonica establishes a species-specific phoresy with Parastrachia japonensis. Dauer larvae (DL), the non-feeding and phoretic stage of C. japonica, are predominantly found on female phoretic hosts, but the mechanisms underlying the establishment of this phoresy remain unknown. To determine whether C. japonica DL are able to recognize and orient themselves to a host using a volatile cue from the host, we developed a Y-tube olfactory assay system in which C. japonica DL were significantly attracted to the air from P. japonensis but not to the air from three other insects or to CO2. These results demonstrated that C. japonica DL utilize volatiles for host recognition and orientation and that the presence of a specific volatile kairomone released by the host attracts C. japonica DL.
authors: Laboratory of Nematology, Department of Applied Biological Sciences, Faculty of Agriculture, Saga University, Saga 840-8502, Japan The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima 890-8580, Japan.
authors: Etsuko
authors: E
authors: Okumura
authors: Laboratory of Nematology, Department of Applied Biological Sciences, Faculty of Agriculture, Saga University, Saga 840-8502, Japan tyoshiga@cc.saga-u.ac.jp.
authors: Toyoshi
authors: T
authors: Yoshiga
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D002107:Caenorhabditis / Q000187:drug effects* / Q000502:physiology*; D006790:Host-Parasite Interactions; D007313:Insecta / Q000469:parasitology*; D010675:Pheromones; D013045:Species Specificity; D055549:Volatile Organic Compounds / Q000494:pharmacology*
chemical_list: D010675:Pheromones; D055549:Volatile Organic Compounds
keywords: Dauer; Kairomone; Navigation; Nictation; Olfactometer