Biology, monitoring, and management of Campylomma verbasci (Meyer) (Hemiptera: Miridae) in Washington apple orchards

Campylomma verbasci is a serious, but sporadic pest on certain apple varieties in Washington. First generation nymphs damage fruit of certain apple varieties when they insert their stylets into blossoms and developing fruit to feed on sap. The purposes of this study were to investigate its biology, behavior, incidence of damage, and to develop tactics for its management.; Fruit of ‘Golden Delicious’ apples were susceptible to damage by C. verbasci feeding primarily during the bloom period and no damage occurred after 12.7 mm stage of fruit development. The availability of prey (spider mites or aphids) did not reduce the incidence of damage.; Limb tap sampling was used to monitor C. verbasci in apple orchards and determine its phenology in Washington. Emergence of the first generation varied from year to year and was not synchronized with a specific stage of apple phenology. A degree-day model was developed from field data to predict emergence of the first generation. This model predicted emergence events within ±3 days of observed events 87% of the time. A degree-day model for predicting population levels was also developed.; A pheromone-based monitoring program was developed. There was a relationship between captures of adult males during fall and densities of first generation nymphs the following spring. Risk thresholds were developed based on this relationship.; The efficacy of various insecticides, rates, and treatment timings were tested against C. verbasci. Chlorpyrifos, formetenate hydrochloride, and endosulfan were the most effective materials. Insecticides treatments applied during the pink to bloom stages were most effective and post bloom treatments were not effective.; C. verbasci were wide-spread through central Washington, but generally did not reach economic levels in commercial orchards. However, high populations and damage levels consistently occurred in untreated research sites. EILs were established for C. verbasci on ‘Delicious’ and ‘Golden Delicious’ for Washington and differed from those established for British Columbia.; In an investigation of the influence of alternative hosts on orchard populations of C. verbasci, neither local populations of Verbascum thapsus (common mullein) nor Aphis pomi (green apple aphid) influenced orchard populations of C. verbasci .