SEASONALITY OF PREDACEOUS PLANT BUGS (HETEROPTERA, MIRIDAE) AND PHYTOPHAGOUS THRIPS (THYSANOPTERA, THRIPIDAE) AS INFLUENCED BY HOST-PLANT PHENOLOGY OF NATIVE AZALEAS (ERICALES, ERICACEAE)

Seasonal synchrony of pbytophagous insects, especially Heterothrips azaleae Hood, and the predaceous mirids Dicyphus rhododendri Dolling and Rhinocapsus vanduzeei Uhler, was determined on five species of native deciduous azaleas (Rhododendron spp.) during 1990-1993. Florida, Alabama, Piedmont, and Flame azaleas supported populations of H. azaleae; Plumleaf azalea did not. Peak adult and larval activity of this species of thrips varied with sequence of flowering during April and May. While R. vanduzeei was present on all azalea species, except Plumleaf, D. rhododendri was found to be abundant only on Florida azalea and occurred more rarely on Alabama azalea. Dicyphus rhododendri nymphs emerged in late March or early April, 2-3 wk before R. vanduzeei nymphs emerged from overwintering eggs, which were inserted into the woody plant tissue. Adult D. rhododendri became scarce after mid-May. Rhinocapsus vanduzeei adults were present until the last week of June. Although both species are known to be pollen feeders, scavengers, or both, they were observed to be active effective predators of thrips and other small insects in the field and in laboratory tests. Additional thrips species collected.were Terebrantia: Frankliniella tritici (Fitch), Anaphothrips obscurus (Muller), Chaetanaphothrips orchidii (Moulton), Thrips nigropilosus Uzel, and Tubulifera: Leptothrips mali (Fitch). Seasonal occurrence of additional phytophagous Hymenoptera, Lepidoptera, and Homoptera are given.