The commercial apple (Malus spp.) orchard ecosystem in Quebec has a diverse fauna of predacious mites. A systematic 2-yr survey showed Amblyseius fallacis (Garman), Typhlodromus caudiglans Schuster (Acari: Phytoseiidae), and Agistemus fleschneri Summers (Acari: Stigmaeidae) to be the most abundant species. Other phytoseiids, Typhlodromus conspicuous (Garman), Typhlodromus herbertae Chant, Typhlodromus longipilus Nesbitt, Typhlodromus bakeri (Garman), Typhlodromus pyri Scheuten, Amblyseius okanagensis (Chant), and Amblyseius finlandicus (Oudemans), were found in low numbers. Two of these species, A. finlandicus and T. conspicuus, were identified for the first time in Quebec. Other occasional species included Anystis baccarum (L.) (Acari: Anystidae) and Balaustium sp. (Acari: Erythraeidae). Tetranychid mite numbers were always less than two mites per leaf throughout the study, and none of the commercial orchards required an acaricide treatment. A notable aspect of this study was that seasonal totals for A. fleschneri and A. fallacis decreased 7.3- and 42.2-fold, respectively, whereas T. caudiglans increased 9.1-fold from 1999 to 2000. Possible mechanisms for these changes, including variations in winter mortality, competition for food, and intraguild predation are discussed.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 99 • No. 3