title: Imidacloprid Extraction from Citrus Leaves and Analysis by Liquid Chromatography-Mass Spectrometry (HPLC-MS/MS).
abstract: A procedure was developed to extract Imidacloprid (IMD) from newly-flushed and fully-expanded citrus leaves. The extraction was conducted in a bullet blender, using a small sample mass (0.5 g of fresh tissue), stainless-steel beads (24 g), and methanol as extractant (10 mL). The extracts did not require further clean-up before analysis by HPLC-MS/MS. The method was validated with control samples from IMD-untreated Hamlin orange trees. The method limit of detection and limit of quantitation were 0.04 and 0.12 μg g(-1), respectively. IMD recoveries from fortified leaf tissue were between 92 % and 102 %, with relative standard deviations of <8 %. The method was further evaluated by extracting leaves from Hamlin orange trees treated with IMD. The treated trees showed maximum concentrations of 10.8 and 21.8 µg g(-1), observed at 20 days after applying two soil-drenching rates (0.51 and 1.02 kg IMD ha(-1)), respectively. This extraction technique will generate useful data on IMD plant uptake, foliar concentration, and correlations with Asian citrus psyllid (ACP) mortality or control. The method could be used to generate baseline data to improve IMD soil-drenching applications as the main management practice to control the ACP.
authors.affiliation: Soil and Water Science Department, Institute of Food and Agricultural Sciences (IFAS), University of Florida (UF), P.O. Box 110290, Gainesville, FL, 32611, USA. jorge.leiva@ufl.edu.
authors.forename: Jorge A
authors.initials: JA
authors.lastname: Leiva
authors.affiliation: Soil and Water Science Department, Institute of Food and Agricultural Sciences (IFAS), University of Florida (UF), P.O. Box 110290, Gainesville, FL, 32611, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Nkedi-Kizza
authors.affiliation: Food and Environmental Toxicology Laboratory, UF-IFAS, P.O. Box 110720, SW 23rd Drive, Gainesville, FL, 32611, USA.
authors.forename: Wlodzimierz S
authors.initials: WS
authors.lastname: Borejsza-Wysocki
authors.affiliation: Food and Environmental Toxicology Laboratory, UF-IFAS, P.O. Box 110720, SW 23rd Drive, Gainesville, FL, 32611, USA.
authors.forename: Victor S
authors.initials: VS
authors.lastname: Bauder
authors.affiliation: Soil and Water Science Department, South West Florida Research and Education Center, UF-IFAS, 2685 SR 29 North, Immokalee, FL, 34142, USA.
authors.forename: Kelly T
authors.initials: KT
authors.lastname: Morgan
mesh_terms: D002851:Chromatography, High Pressure Liquid; D002957:Citrus; D007093:Imidazoles / Q000032:analysis* / Q000737:chemistry; D007306:Insecticides / Q000032:analysis* / Q000737:chemistry; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000032:analysis* / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry*; D053719:Tandem Mass Spectrometry
chemical_list: D007093:Imidazoles; D007306:Insecticides; D000073943:Neonicotinoids; D009574:Nitro Compounds; C082359:imidacloprid
keywords: Diaphorina citri; Foliar concentration; Huanglongbing; Neonicotinoid; Systemic pesticide