Effects of the biological nematicide, DiTera (R), on hatching of Globoderarostochiensis and G-pallida

DiTera(R) (Valent Biosciences Corp.), a novel biological nematicide, did no t stimulate hatch of Globodera rostochiensis or G. pallida, but exposing cy sts to 1 and 10% DiTera(R) in distilled water for 5 weeks irreversibly prev ented hatch when the cysts were transferred to the natural hatching stimulu s potato root diffusate (PRD). Similarly, exposing cysts of both species fo r 5 weeks to 1 and 10% DiTera(R) dissolved in PRD resulted in a significant inhibition of hatch which was irreversible when cysts were transferred to PRD alone. Tests on free eggs indicated that, when mixed with PRD, DiTera(R ) prevented eggshell permeability change, normally caused by PRD as an init ial phase in the hatching process, in a majority of eggs. This indication t hat DiTera(R) interfered with the specific hatching mechanism of G. rostoch iensis was reinforced by the lack of hatch inhibition of Meloidogyne incogn ita. The potential for DiTera(R) as a novel control agent to prevent hatch of G. rostachiensis or G. pallida in the held is discussed.