POPULATION SUPPRESSION OF CAMPYLOMMA-VERBASCI (HETEROPTERA, MIRIDAE) BY ATMOSPHERIC PERMEATION WITH SYNTHETIC SEX-PHEROMONE

Suppression of overwintering populations of Campylomma verbasci (Meyer ) by atmospheric permeation with synthetic sex pheromone, 16:1 butyl b utyrate:2(E)-crotyl butyrate, was evaluated in apple orchards in the O kanagan Valley of British Columbia. Five 1-ha plots were each treated throughout late summer and fall 1993 and 1994 with 1,000 polyurethane dispensers (118 mg load per dispenser). In 1993, dispensers were deplo yed singly. In 1994, 4 of 5 orchards were treated with 500 double-disp enser release points per hectare; the 5th orchard was treated as in 19 93. Total pheromone applications modeled from laboratory release rates and hourly field temperatures were estimated to be 78.9 g/ha over 84 d and 80.6 g/ha over 75 d in 1993 and 1994, respectively. Compared wit h control plots, catches of adult males in pheromone-baited traps in t reated plots from August to November in both years were reduced on ave rage by 96%. Numbers of overwintering eggs laid in the fall were asses sed the following spring by counting nymphs hatching from field-collec ted prunings and by limb-tap samples. In 1994, numbers of Ist-generati on nymphs were reduced significantly on average by 71 and 81% in 4 of 5 orchards as assessed by prunings and limb taps, respectively; damage samples at harvest corroborated these results. Switching from 1,000 t o 500 release points per hectare in 1994 lessened the impact of treatm ent on numbers of Ist-generation nymphs in 1995. Despite reductions in numbers of overwintering nymphs, results were not consistent enough t o suggest commercialization at this time. Because recent evidence show s that the dispensers may have been deployed after females had begun t o lay overwintering eggs, efficacy might be improved by implementing t reatments in mid-July. This is the first reported example of atmospher ic permeation with synthetic sex pheromone causing a reduction in the population density of a heteropteran.