Environmental Entomology (1981) 10, 313-319
Donn T. Johnson and B.A. Croft (1981)
Dispersal of Amblyseius fallacis (Acarina: Phytoseiidae) in an apple ecosystem
Environmental Entomology 10 (3), 313-319
Abstract: Dispersal of the predatory phytoseiid mite Amblyseius fallacis (Garman) within the ground cover, the air beneath the tree canopy, on the tree trunk and on tree foliage of commercial apple orchards during a growing season is described in relation to environmental factors and densities of A. fallacis and its prey Panonychus ulmi (Koch), Tetranychus urticae Koch, and Aculus schlechtendali (Nalepa) in the aforenamed habitats. Ambulatory and aerial means of dispersal were involved in initial colonization of trees by A. fallacis coming from the orchard ground cover. A mean total of 261°D (base 12.2°C) since January 1 plus the presence of predators in the ground cover and prey in excess of one P. ulmi equivalent/apple leaf, i.e., the number of P. ulmi + T. urticae + (A. schlechtendali/15) on an apple leaf, were prerequisites for tree colonization by A. fallacis. Aspects of density independent and dependent dispersal by A. fallacis from trees to sites within and beyond an orchard in response to prey are also reported.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Donn T. Johnson
Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
population dynamics/epizootiology
