Lure and starve: Host root exudates to suppress field populations of cyst nematodes

Abstract

Plant parasitic nematodes are a burden to global food security, accounting for substantial yield losses in agricultural production worldwide. Increasing concerns over the environment and health issues have led to diminishing control options at the disposal of agricultural producers. Lure and starve, a strategy that is based on stimulating hatching of second stage juveniles (J2) of some cyst forming plant parasitic nematodes in the absence of their host plant seems a promising approach to maintain sustainability in crop production. Here we examined in-situ hatching of encysted eggs of the potato cyst nematode Globodera pallida and the carrot cyst nematode Heterodera carotae following exogenous applications of host root exudates in repeated field experiments during autumn and spring seasons. Population densities (viable J2 g−1 of soil) were assessed prior and post-application of root exudates. Results showed hatching induction of up to 83 % for G. pallida and 54 % for H. carotae in field plots drenched with their respective host root exudates. Spring season experiments were characterised by limited soil moisture and did not reduce nematode population densities for G. pallida. The potential for host root exudates in suppressing field population of cyst nematode in lure and starve strategies looks promising for both cyst nematode species investigated.