Capsules containing entomopathogenic nematodes as a Trojan horse approach to control the western corn rootworm

Ivan Hiltpold, Bruce Elliott Hibbard, B. W. French & Ted Turlings

Résumé Aims The use of entomopathogenic nematodes in the biological control of soil insect pests is hampered by the costly and inadequate application techniques. As a possible solution we evaluated a nematode encapsulation approach that offers effective application and may possibly attract the pest by adding attractants to the capsule shell.
Methods Heterorhabditis bacteriophora nematodes, which show high virulence against the maize root pest Diabrotica virgifera virgifera, were encapsulated in a polysaccharide shell derived from the algae Laminaria ssp. Shells of varying thickness and composition were evaluated.
Results Nematodes readily survived the encapsulation process and were able, varying with shell thickness and temperature, to break through the shell and subsequently infect hosts. The added attractants and feeding stimulants to the shell attracted the pest larvae as much as maize roots. In field trials, encapsulated H. bacteriophora nematodes were more effective in controlling D. v. virgifera than those sprayed in water over the soil surface, but in these trials the addition of stimulants did not increase the control efficiency.
Conclusions The study demonstrates that nematodes can be successfully applied in capsules in the field. Further improvements are needed to make the capsules a cost effective alternative to conventional field application of nematodes.
Mots-clés entomopathogenic nematodes, heterorhabditis bacteriophora, heterorabditidae, western corn rootworm, diabrotica virgifera virgifera, chrysomelidae, application technique, biological control, belowground pest management, plant protection, chrysomelidae larval injury, gas-exchange parameters, biological-control, steinernema-carpocapsae, entomogenous nematode, host location, neoaplectana-carpocapsae, infected cadavers, calcium alginate, carbon-dioxide
Citation Hiltpold, I., Hibbard, B. E., French, B. W., & Turlings, T. (2012). Capsules containing entomopathogenic nematodes as a Trojan horse approach to control the western corn rootworm. Plant and Soil, 358(1-2), 10-24.
Type Article de périodique (Anglais)
Date de publication 2012
Nom du périodique Plant and Soil
Volume 358
Numéro 1-2
Pages 10-24