Imidacloprid sorption kinetics, equilibria, and degradation in sandy soils of Florida.
Imidacloprid (IMD) is a neonicotinoid insecticide soil-drenched on sandy soils of southwest Florida for the control of Diaphorina citri Kuwayama or Asian citrus psyllid (ACP). The ACP vectors causal pathogens of a devastating citrus disease called citrus greening. Understanding the behavior of IMD in these soils and plants is critical to its performance against target pests. Samples from Immokalee fine sand (IFS) were used for sorption kinetics and equilibria experiments. IMD kinetics data were described by the one-site mass transfer (OSMT) model and reached equilibrium between 6 and 12 h. Batch equilibrium and degradation studies revealed that IMD was weakly sorbed (K(OC) = 163-230) and persistent, with a half-life of 1.0-2.6 years. Consequently, IMD has the potential to leach below the citrus root zone after the soil-drench applications.
†Soil and Water Science Department, Institute of Food and Agricultural Sciences, University of Florida, Post Office Box 110290, Gainesville, Florida 32611, United States.
Jorge A
JA
Leiva
†Soil and Water Science Department, Institute of Food and Agricultural Sciences, University of Florida, Post Office Box 110290, Gainesville, Florida 32611, United States.
Peter
P
Nkedi-Kizza
Kelly T
KT
Morgan
Jawwad A
JA
Qureshi
D000818:Animals; D005431:Florida; D006430:Hemiptera / Q000187:drug effects; D007093:Imidazoles / Q000737:chemistry* / Q000494:pharmacology; D007306:Insecticides / Q000737:chemistry* / Q000494:pharmacology; D007700:Kinetics; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000737:chemistry* / Q000494:pharmacology; D010935:Plant Diseases / Q000469:parasitology* / Q000517:prevention & control; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry / Q000494:pharmacology
D007093:Imidazoles; D007306:Insecticides; D000073943:Neonicotinoids; D009574:Nitro Compounds; D012987:Soil; D012989:Soil Pollutants; C082359:imidacloprid
Asian citrus psyllid; integrated pest management; one-site mass transfer; pesticide transport; soil partition coefficient; zero-order transformation