Uptake and retention of imidacloprid and cyantraniliprole in cotton (Gossypium hirsutum) for the control of Bemisia tabaci (Hemiptera: Aleyrodidae)

Authors: PERIER, JERMAINE - University Of Georgia; LAGALANTE, ANTHONY - Villanova University; MCCARTHY, ELIZABETH - University Of Georgia; Simmons, Alvin; RILEY, DAVID - University Of Georgia

Submitted to: Journal of Entomological Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/23/2023
Publication Date: 9/7/2023
Citation: Perier, J.D., Lagalante, A.F., Mccarthy, E.P., Simmons, A.M., Riley, D.G. 2023. Uptake and retention of imidacloprid and cyantraniliprole in cotton (Gossypium hirsutum) for the control of Bemisia tabaci (Hemiptera: Aleyrodidae). Journal of Entomological Science. 58(4):434-446. https://doi.org/10.18474/JES22-77.
DOI: https://doi.org/10.18474/JES22-77

Interpretive Summary: To be effective, insecticides that are delivered by drench application depend on (1) the ability of a plant to uptake the insecticides by its roots, (2) the ability of the insecticides to move throughout the plant, and (3) the ability of the plant to retain the insecticide long enough to kill the target insect pests. There is a need for a standard assay in insecticide efficacy trials to explain dose-response concentrations. Imidacloprid and cyantraniliprole are two insecticides that are commonly used as drench applications to manage whiteflies and other sucking insects in many fruit, vegetable, and row crops. A study was done which evaluated the uptake of systemic root drenches of an imidacloprid (Admire® Pro 4F) and a cyantraniliprol (Exirel® 0.83SC) in seedling cotton test plants. The results indicated higher active-ingredient retention with higher concentrations of insecticide treatments in the dose-response assays, and allows for the prediction of insecticide concentration in leaf tissue from root drench applications. The findings from this study will be useful to agricultural scientists and crop protection practitioners.

Technical Abstract: Plant tissue bioassays are standard among insecticide efficacy evaluations. In particular, plant leaves are typically used for bioassaying leaf-feeding insects like whiteflies. A systemic root drench of two major insecticides that are used for whitefly control, imidacloprid (Admire® Pro 4F) and cyantraniliprole (Exirel® 0.83SC), were evaluated to estimate an expected leaf residue content in 3-week-old cotton seedlings. The seedlings with washed root systems were allowed to imbibe a series of concentrations of each insecticide for 24h before drying the plants for one week for processing. Insecticide active-ingredient quantification via liquid chromatography-mass spectrometry using standard insecticide checks was carried out. The results indicated significant active-ingredient retention with higher concentrations of insecticide treatments. Specifically, for imidacloprid and cyantraniliprole, the average slope and intercept of the log ppb leaf residue to mgai solution concentration around the roots were y = 4.08 x + 0.83 and y = 6.22 x + 0.47, respectively. This methodology predicts insecticide concentration in cotton leaf tissue from root drench application.