Abstract
Plant parasitic nematodes, especially parasitic root-knot nematodes, are one of the most destructive plant pathogens worldwide. The control of plant root-knot nematodes is extremely challenging. Duddingtonia flagrans is a type of nematode-trapping fungi (NTF), which produces three-dimensional adhesive networks to trap nematodes. In this study, the pathogenicity and volatile organic compounds (VOCs) of the NTF D. flagrans against the plant root-knot nematode, Meloidogyne incognita, were investigated. The predatory process of D. flagrans trapping M. incognita was observed using scanning electron microscopy. Gas chromatography-mass spectrometry analysis of the VOCs from D. flagrans led to the identification of 52 metabolites, of which 11 main compounds were tested individually for their activity against M. incognita. Three compounds, cyclohexanamine, cyclohexanone, and cyclohexanol, were toxic to M. incognita. Furthermore, these three VOCs inhibited egg hatching of M. incognita. Cyclohexanamine showed the highest nematicidal activity, which can cause 97.93% mortality of M. incognita at 8.71 µM within 12 h. The number of hatched juveniles per egg mass after 3 days was just 8.44 when treated with 26.14 µM cyclohexanamine. This study is the first to demonstrate the nematicidal activity of VOCs produced by D. flagrans against M. incognita, which indicates that D. flagrans has the potential to biocontrol plant root-knot nematodes.
Highlights
Plant parasitic nematodes infect a variety of crops and cause severe damage, which leads to annual economic losses estimated at $173 billion [1]
Petri dishes were removed from the incubator and suspension containing approximately 200–300 J2s of M. incognita was added to the D. flagrans
The lack of safer and more effective nematicides has accelerated the search for more natural products
Summary
Plant parasitic nematodes infect a variety of crops and cause severe damage, which leads to annual economic losses estimated at $173 billion [1]. Nematophagous fungi, natural enemies of plant parasitic nematodes, have been suggested as promising resources for the biological control of nematodes. They can exist in diverse environments, and some of them can switch from being saprotrophic to predatory when nematodes are present [3]. Based on the analysis of gas chromatography-mass spectrometry (GC-MS) and confirmation with commercial compounds, three compounds (cyclohexanamine, cyclohexanone, and cyclohexanol) were toxic to both juveniles and eggs of M. incognita This implies that the NTF D. flagrans can infect nematodes by shaping the trap device and producing active metabolites
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
