Fungal Biocontrol Agents for Nematode Management in Organic Agriculture

Plant parasitic nematodes (PPNs) are one of the most serious constraints in food security. Among the many biocontrol agents studied for managing PPNs, nematophagous fungi show a high potential. These fungi control/suppress the nematode population either by parasitising or predating/trapping various nematode stages or kill them by secretion of nematotoxic metabolites. With more than 700 species of nematophagous fungi identified with a potential of nematode biocontrol, species such as Purpureocillium (Paecilomyces) lilacinus, Pochonia (Verticillium) chlamydosporia and Trichoderma are exploited as nematode parasitic fungi. Among nematode-trapping fungi, Arthrobotrys oligospora is widely used in nematode management. Along with parasitic and trapping species, Arbuscular mycorrhizal fungi (AMF) also offer an exciting opportunity to be integrated in nematode management programs due to their ability to induce systemic resistance and tolerance, competition for space and nutrients. In this chapter we discuss the mechanisms employed by nematophagous fungi in detail. We suggest that formulations incorporating 2 or more fungi with different modes of action should be commercialised to increase efficiency. Due to the enormous demand and availability of spurious products, strict regulations are necessary, nationally and internationally, to benefit the farming community facing PPNs threats.