Effects of six selected orchard insecticides on Neoseiulus fallacis (Acari: Phytoseiidae) in the laboratory.
BACKGROUND
Neoseiulus fallacis (Garman) is a key predator of tetranychid mites in integrated pest management (IPM) programs across Canada. This study identified compounds that would be recommended for tier-II field evaluations in an IPM program.


RESULTS
The overall egg mortality caused by the six insecticides was negligible as it extended from 0 to 12.1%. Imidacloprid was classified as toxic to adults. The label rate was 7.73-fold the LC(50). Thiamethoxam was classified as moderately toxic to adults, and its label rate was 2.87-fold the LC(50). Acetamiprid and spinosad were classified as marginally toxic, and their label rates were respectively 0.99- and 0.45-fold the LC(50) for adults. Thiacloprid and methoxyfenozide were virtually innocuous to adults.


CONCLUSIONS
Methoxyfenozide was totally harmless to all stages of N. fallacis, and it would be included in IPM programs immediately. Acetamiprid, spinosad and thiacloprid had varying degrees of mild toxicity to at least one growth stage of the predator. Therefore, they were recommended for tier-II field testing according to their label claims. Imidacloprid and thiamethoxam were toxic to moderately toxic to adults and had significant adverse effects on fecundity. Therefore, they would be field evaluated only if alternatives were unavailable.
Bostanian
Noubar J
NJ
Horticulture Research and Development Centre, Agriculture and Agri-Food Canada, St Jean-sur-Richelieu, Quebec, Canada. noubar.bostanian@agr.gc.ca
Hardman
John M
JM
Thistlewood
Howard A
HA
Racette
Gaétan
G
D000818:Animals; D004338:Drug Combinations; D006834:Hydrazines / Q000633:toxicity; D007093:Imidazoles / Q000633:toxicity; D007306:Insecticides / Q000633:toxicity*; D007605:Juvenile Hormones / Q000633:toxicity; D007928:Lethal Dose 50; D018942:Macrolides / Q000633:toxicity; D027845:Malus; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000633:toxicity; D010078:Oxazines / Q000633:toxicity; D010572:Pest Control, Biological; D011725:Pyridines / Q000633:toxicity; D040102:Tetranychidae / Q000187:drug effects* / Q000254:growth & development; D000077922:Thiamethoxam; D013843:Thiazines / Q000633:toxicity; D013844:Thiazoles / Q000633:toxicity
D004338:Drug Combinations; D006834:Hydrazines; D007093:Imidazoles; D007306:Insecticides; D007605:Juvenile Hormones; D018942:Macrolides; D000073943:Neonicotinoids; D009574:Nitro Compounds; D010078:Oxazines; D011725:Pyridines; D013843:Thiazines; D013844:Thiazoles; C082359:imidacloprid; C464485:acetamiprid; C406712:methoxyfenozide; D000077922:Thiamethoxam; C417209:thiacloprid; C415329:spinosad