Poster: Biology & Disease Mgmt: Nematology
Mode of action studies on the nematicide fluensulfone
P. NAVIA GINE (1) (1) 1973, Wellington, FL, U.S.A.
Fluensulfone has proven efficacy in the field against a range of nematode species. The mode of action of fluensulfone is however currently unknown. Fluensulfone was found to have nematicidal activity against C. elegans but at concentrations ≥100-fold greater than those reported to be effective against the PPN Meloidogyne javanica. Fluensulfone affected a number of C. elegans behaviours, including locomotion, pharyngeal pumping, egg laying and development. The pharyngeal effects suggested that fluensulfone might influence feeding behaviour in PPNs. In PPNs, the behaviour of the stylet mouth spear is critical in feeding and host invasion. The action of fluensulfone on the stylet of the PPN Globodera pallida was therefore investigated, to validate observations made with C. elegans. The pharmacology of the stylet was also investigated, using knowledge of the C. elegans pharynx as a guide. Fluensulfone stimulated stylet activity and blocked 5-HT-stimulated activity. If metabolic impairment is identified as the causative agent of fluensulfone nematicidal activity this must be further studied through metabolomics and other techniques.