The effects of α-solanine and zinc sulphate on the behaviour of potato cyst nematodes Globodera rostochiensis and G. pallida

Abstract

Two behavioural assays were carried out: one on the attraction of potato cyst nematodes (PCN), Globodera rostochiensis and G. pallida, to solanaceae-specific secondary metabolite α-solanine, the other on the effect of ZnSO4 (a compound known to suppress chemoreceptors). The first assay demonstrated that α-solanine was attractive to second-stage juveniles (J2) of PCN; G. pallida was attracted to concentrations of 10−4 M and 10−5 M, whereas G. rostochiensis was attracted to 10−5 M. Globodera pallida reacted faster than G. rostochiensis to the same concentration of α-solanine. As α-solanine is produced by host plants of PCN, this compound is attributed to kairomones. The response to α-solanine of nematodes pre-exposed to a 3 mM ZnSO4 solution was significantly suppressed compared to that of water control. The effect was observed throughout the whole testing period (30 min). This is the first evidence that both α-solanine and ZnSO4 can affect the behaviour of hatched J2 of PCN.