Nematodes as Potential Biocontrol Agents
Rhabditoid nematodes have been used successfully as microbial insecticides in control programs for other cryptic pests (such as lawn grubs). The restricted movement of A. glabripennis larvae and moist protected environment within their galleries suggest that nematodes, particularly searching species, may have some potential as a control method. Several studies in China found that entomopathogenic nematodes reduced the number of new A. glabripennis emergence holes when they were introduced into trees through existing emergence holes.
Eight species of rhabditoid nematodes were tested for their ability to kill and reproduce in A. glabripennis larvae: Steinernema carpocapsae (Weiser) 1955, Sal strain; Heterorhabiditis bacteriophora Poinar 1976, Lewiston strain; H. indica Poinar, Karunakar and David 1992, HOM-1 strain; H. marelatus Liu & Berry 1996, IN strain, S. feltiae SN from France, S. glaseri NJ from New Jersey, S. riobrave TX from Texas, S. carpocapsae Sal from Indiana, S. carpocapsae All from Georgia, and H. marelata IN from Indiana. They were screened for efficacy against laboratory colonies of Asian longhorned beetle, Anoplophora glabripennis collected from Queens, New York and Chicago, Illinois. Two bioassays were used to screen nematode effects on beetle larvae; a filter paper assay using a 24-h exposure of nematode-to-target-insect, and a diet cup bioassay using a 72-h exposure of host larvae to infective juveniles applied to the larval bore hole made in the artificial diet in the cups.
Potential biocontrol agent that can be applied to trees to kill larvae living inside.
The A. glabripennis larvae were permissive to all four nematode species initially evaluated, however, host mortality, and survival and reproduction of nematodes were highest for H. marelatus and S. carpocapsae. Bioassays with H. marelatus estimated that the lethal dosage (LD5o) was approximately 19 infective juvenile nematodes for second and third instars and 347 nematodes for fourth and fifth instars. H. marelatus infective juveniles on moistened sponges were stapled to oviposition sites on cut logs and were able to locate and invade host larvae within 30 cm galleries.
Solter, LF; Keena, MA; Cate, JR; McManus, M; Hanks, LM. 2001. Infectivity of four species of nematodes (Rhabditoides: Steinernematidae, Heterorhabditiade) to the Asian longhorned beetle, Anoplophora glabripennis (Motchulsky) (Coleoptera: Cerambycidae). Biocontrol Science and Technology 11: 547-552.
First- and third-stage larvae were susceptible to all isolates using a filter paper bioassay. S. feltiae and S. carpocapsae Sal were the most effective, causing 100% mortality. S. feltiae was more infectious than S. carpocapsae Sal against third, sixth, and seventh instars. S. riobrave, S. glaseri, and H. marelata were ineffective against the older instars. In the diet cup bioassay, S. feltiae and S. carpocapsae Sal killed 71–100% of mid-to late instar larvae, but the remaining isolates screened were ineffective. Nematode preconditioning to aqueous A. glabripennis frass extracts inhibited S. carpocapsae Sal infectivity but had no effect on nematode pathogenicity. S. feltiae juveniles were positively attracted to A. glabripennis frass extracts. Our results demonstrate the potential use of S. feltiae and S. carpocapsae isolates as control agents for A. glabripennis.
Fallon, DJ; Solter, LF; Keena, MA; McManus, M; Cate, JR; Hanks, LM. 2004. Effects of entomopathogenic nematodes on the Asian longhorned beetle, Anoplophora glabripennis (Motchulsky) (Coleoptera: Cerambycidae). Biological Control 30: 430-438.
- Leellen Solter, Illinois Natural History Survey
- Fallon DJ, Illinois Natural History Survey
- Melody Keena, US Forest Service- Northern Research Station Research Entomologist
- Michael McManus, US Forest Service- Northern Research Station Research Entomologist Emeritus
- Larry Hanks, University of Illinois
- J. Cate, Integrated Biocontrol Systems
Last Modified: 07/13/2017