Occurrence of the western flower thrips, Frankliniella occidentalis, and potential predators on host plants in nearorchard habitats of Washington and Oregon (Thysanoptera: Thripidae).

摘要

One hundred thirty species of native and introduced plants growing in uncultivated land adjacent to apple and pear orchards of central Washington and northern Oregon were sampled for the presence of the western flower thrips (WFT) Frankliniella occidentalis (Pergande, 1895) and potential thrips predators. Plants were sampled primarily while in flower. Flowering hosts for WFT were available from late-March to late-October. Adult WFT occurred on 119 plant species and presumed WFT larvae were present on 108 of 119 species. Maximum observed WFT density on several plant species exceeded 100 individuals (adults and larvae) per gram dry weight of plant material. The most abundant predator was Orius tristicolor (White, 1879) (Heteroptera: Anthocoridae). It was collected on 64 plant species, all of which were hosts for WFT. The second most abundant predators were spiders (Araneae). Small spider immatures (first and second instars) of several species were common on certain host plants, and are likely to feed on WFT.