Pest Management Science (2012) 68, 529-536

Sara R. Tanis, Bert M. Cregg, David Mota-Sanchez, Deborah G. McCullough and Therese M. Poland (2012)
Spatial and temporal distribution of trunk-injected 14C-imidacloprid in Fraxinus trees
Pest Management Science 68 (4), 529-536
Abstract: BACKGROUND: Since the discovery of Agrilus planipennis Fairmaire (emerald ash borer) in 2002, researchers have tested several methods of chemical control. Soil drench or trunk injection products containing imidacloprid are commonly used to control adults. However, efficacy can be highly variable and may be due to uneven translocation of systemic insecticides. The purpose of this study was to determine whether sectored xylem anatomy might influence imidacloprid distribution in tree crowns.
RESULTS: Imidacloprid equivalent concentrations were higher in leaves from branches in the plane of the injection point (0°) than in leaves from branches on the opposite side of the injection point (180°). Leaves from branches 90° to the right of injection points had higher imidacloprid equivalent concentrations than leaves from branches 90° to the left of injection points. Leaves and shoots had higher imidacloprid equivalent concentrations than roots and trunk cores, indicating that imidacloprid moves primarily through the xylem.
CONCLUSION: Imidacloprid equivalent concentration in leaves varied over time and in relation to injection points. It is concluded that ash trees have sectored 'zigzag' xylem architecture patterns consistent with sectored flow distribution. This could lead to variable distribution of imidacloprid in tree crowns and therefore to variable control of A. planipennis.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Sara R. Tanis, Deborah G. McCullough, Therese M. Poland

Research topic(s) for pests/diseases/weeds:
control - general

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Agrilus planipennis	Ash (Fraxinus)