title: Clothianidin and Imidacloprid Residues in Poa annua (Poales: Poaceae) and Their Effects on Listronotus maculicollis (Coleoptera: Curculionidae).
abstract: Competitive enzyme-linked immunosorbent assay was used to quantify the amounts of the neonicotinoids clothianidin and imidacloprid in Poa annua L. clippings from treated golf course fairways. Average clothianidin residues 7 d after application ranged from 674 to 1,550 ng/g tissue in 2012 and 455-2,220 ng/g tissue in 2013. Average clothianidin residues the day of application ranged from 17,100-38,800 ng/g tissue in 2014. Average imidacloprid residues 7 d after treatment ranged from 1,950-3,030 ng/g tissue in 2012 and 7,780-9,230 ng/g tissue in 2013. Average imidacloprid residues the day of application ranged from 31,500-40,400 ng/g tissue in 2014. Neonicotinoid or bifenthrin-neonicotinoid combination products applied in field plots in 2012 did not significantly reduce the numbers of larvae relative to the untreated control. However, in 2013, statistically significant reductions in the numbers of larvae recovered from treated field plots were associated with the presence of bifenthrin alone or when used in combination with neonicotinoid active ingredients. Listronotus maculicollis (Kirby) adults caged on neonicotinoid-, bifenthrin-, and bifenthrin-neonicotinoid-treated P. annua turf plugs fed on P. annua leaves, but mortality was only highly significantly different between treated and untreated foliage when weevils were placed on treated foliage the day after treatment and allowed to feed for 7 d. The modest degree of population suppression with bifenthrin in these experiments may not be adequate to justify the continued use of these products due to the increased risk of insecticide resistance and disruption of biological control.
authors.affiliation: Department of Plant Sciences and Entomology, University of Rhode Island, Kingston, RI 02881.
authors.forename: Christopher
authors.initials: C
authors.lastname: Clavet
authors.affiliation: Department of Plant Sciences and Entomology, University of Rhode Island, Kingston, RI 02881.
authors.forename: Matthew
authors.initials: M
authors.lastname: Requintina
authors.affiliation: Department of Plant Sciences and Entomology, University of Rhode Island, Kingston, RI 02881.
authors.forename: Emily
authors.initials: E
authors.lastname: Hampton
authors.affiliation: Valley Laboratory, The Connecticut Agricultural Experiment Station, 153 Cook Hill Rd., Windsor, CT 06095.
authors.forename: Richard S
authors.initials: RS
authors.lastname: Cowles
authors.affiliation: Department of Entomology, University of California, Riverside, 900 University Ave., Riverside, CA 92521.
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Byrne
authors.affiliation: Department of Plant Sciences and Entomology, University of Rhode Island, Kingston, RI 02881. stevealm@uri.edu.
authors.forename: Steven R
authors.initials: SR
authors.lastname: Alm
mesh_terms: D000818:Animals; D006146:Guanidines / Q000032:analysis*; D007093:Imidazoles / Q000032:analysis*; D007814:Larva; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*; D031785:Poa / Q000737:chemistry*; D013844:Thiazoles / Q000032:analysis*; D048889:Weevils
chemical_list: D006146:Guanidines; D007093:Imidazoles; D000073943:Neonicotinoids; D009574:Nitro Compounds; D010573:Pesticide Residues; D013844:Thiazoles; C480342:clothianidin; C082359:imidacloprid
keywords: ELISA; Listronotus maculicollis; bifenthrin; clothianidin; imidacloprid