Arbuscular mycorrhizal fungi enhance the efficacy of Solanum trap crops against potato cyst nematodes

Potato cyst nematodes cause significant yield losses in potato crops worldwide. Trap cropping with non-host solanaceous species offers a sustainable alternative to chemical control by inducing nematode hatching without supporting lifecycle completion. However, trap crop efficacy is often limited by poor establishment under nutrient-deficient conditions. Arbuscular mycorrhizal (AM) fungi, known to enhance plant growth through improved nutrient acquisition, may strengthen trap crop performance. This study investigated whether AM fungi colonise Solanum trap crops (S. chenopodioides and S. scabrum) and assessed their impact on Globodera pallida suppression. Both plant species were colonised by AM fungi, resulting in increased root biomass. In sterile and field soils, AM fungal inoculation significantly enhanced the ability of trap crops to reduce G. pallida populations compared to AM-free plants. Furthermore, root leachates from AM-colonised trap crops induced greater expression of the nematode hatching gene Gp-nep-1, suggesting amplified hatch stimulation. These findings demonstrate that AM fungi improve both growth and biological efficacy of Solanum trap crops, positioning AM-enhanced trap cropping as a potential strategy for integrated G. pallida management.