Mode of action of fosthiazate used for the control of the potato cyst nematode Globodera pallida

Fosthiazate (Nemathorin 10G Ishihara Sangyo Kaisha Ltd, Japan) is a new nem aticide approved for use on potatoes Solanum tuberosum L. in the UK for the control of the potato cyst nematodes Globodera rostochiensis (Woll). Skarb ilovich and G. pallida (Stone). Fosthiazate delayed and suppressed hatch of the potato cyst nematode Globodera pallida in both in vitro laboratory tes ts and a glasshouse pot experiment. In vitro hatch was temporarily inhibite d by fosthiazate concentrations above 0.09 mu g ml(-1) and increasing the f osthiazate concentration further prolonged the duration of hatch inhibition . Analysis of fosthiazate soil concentrations, using high-pressure liquid c hromatography, during the glasshouse experiment showed that hatch was suppr essed in the soil at concentrations above 0.5 mg kg(-1). Other factors such as the paralysis of hatched nematodes in the soil solution are also involv ed.