Competitive interactions between entomopathogenic nematodes and parasitoid venom

0524136 - BC 2021 RIV US eng J - Journal Article
Shaik, Haq Abdul - Mishra, Archana - Hussein, H. M. - Skoková Habuštová, Oxana - Sehnal, František
Competitive interactions between entomopathogenic nematodes and parasitoid venom.
Journal of Applied Entomology. Roč. 144, č. 6 (2020), s. 481-490. ISSN 0931-2048. E-ISSN 1439-0418
R&D Projects: GA MZe(CZ) QK1910270; GA MŠMT ME 907
Institutional support: RVO:60077344
Keywords : biological control * Habrobracon hebetor * Spodoptera littoralis
OECD category: Agronomy, plant breeding and plant protection
Impact factor: 2.603, year: 2020
Method of publishing: Limited access
https://onlinelibrary.wiley.com/doi/full/10.1111/jen.12750

Entomopathogenic nematodes and parasitoid larvae of some wasps play important roles in the natural control of the pest insects. However, it has not been excluded that competition between nematodes and wasps may in some cases reduce their efficacy in the pest control. Using caterpillars of Spodoptera littoralis we examined interactions between the nematode Steinernema carpocapsae and the venom of the parasitoid Habrobracon hebetor. The survival of S. littoralis caterpillars was reduced in dose dependent manner when 5 to 500 nematodes or 0.005 – 0.1 venom units were applied to single caterpillars. High doses of either nematodes or the venom caused death within 1-3 days in all treated hosts. The low doses of nematodes killed caterpillars within a week, in some cases when they attempted to pupate. Low venom doses were characterized by extended survival terminated with death due to starvation. Combined treatment of nematodes and the venom were mutually synergistic and elicited severe lethal effects. The nematodes were fully resistant to the venom and can feed and grow on the symbiotic bacteria in vitro. The venom impairs food processing and causes death of caterpillars due to starvation. Disruption of the hormonal regulation of metamorphosis by ecdysteroids and juvenile hormone was apparently responsible for defective molts block at different stages of the molting process, regionally restricted molting, and molts to “intermediates” combining regions of newly secreted larval and pupal cuticles.
Permanent Link: http://hdl.handle.net/11104/0311598