Environmental Entomology (1995) 24, 446-453
B. W. Strong and B.A. Croft (1995)
Inoculative release of phytoseiid mites (Acarina: Phytoseiidae) into the rapidly expanding canopy of hops for control of Tetranychus urticae (Acarina: Tetranychidae)
Environmental Entomology 24 (2), 446-453
Abstract: Biological control of Tetranychus urticae Koch was studied on hops, Humulus lupulus L., a rapidly growing perennial crop, in western Oregon. Single or mixed species of Neoseiulus fallacis (Garman), Metaseiulus occidentalis (Nesbitt), Typhlodromus pyri Scheuten, and Amblyseius andersoni Chant were released inoculatively into individual plants in 1992-1993. Success of T. urticae control depended on the phytoseiid species released and the ratios and distributions of pest and predaceous mites. The most effective control was by N. fallacis or M. occidentalis or a mixture of both species. In 1993, M. occidentalis provided poor control, probably because of cool weather. T. pyri and A. andersoni provided some control, but always less than N. fallacis and M. occidentalis. Analysis of spatial distributions indicated that both N. fallacis and M. occidentalis dispersed throughout hop plants if T. urticae were not abundant, but they stayed on the lower parts of the plant when T. urticae were abundant. Factors governing the distributions and dispersal of T. urticae and phytoseiids on hops and the effectiveness of biological control are discussed.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
evaluation - screening - selection
