Thrips-parasitic nematodes

Definition

Entomopathogenic nematodes in the families Steinernematidae and Heterorhabditidae that actively seek, infect, and kill thrips (Thysanoptera), typically entering through natural body openings and releasing symbiotic bacteria that cause lethal septicemia. These nematodes are deployed as biological control agents against pest thrips in greenhouse and field crops, with Steinernema feltiae being the most widely studied and commercialized species for this target.

Etymology

Example

Steinernema feltiae applied as a soil drench reduces populations of western flower thrips (Frankliniella occidentalis) in greenhouse ornamentals by infecting pupae in the substrate; however, efficacy against foliar-feeding adults is limited because nematodes require moist conditions and direct contact with host stages.

Synonyms

• thrips-parasitic entomopathogenic nematodes

Related Terms

• entomopathogenic nematodes
• Biological control
• Steinernematidae
• Heterorhabditidae
• Thysanoptera
• western flower thrips
• Integrated Pest Management
• soil-dwelling entomopathogens

Usage Notes

Distinguish from nematodes that parasitize thrips as obligate, vertically transmitted associates (rare) versus the more common facultative, horizontally transmitted entomopathogenic nematodes used in biocontrol. The term is functional, not taxonomic—species within Steinernema and Heterorhabditis vary in thrips host range and virulence. Field efficacy depends critically on application timing relative to thrips life stage, substrate moisture, and temperature.