BIONOMICS OF STRAWBERRY ROOT WEEVIL ADULTS, OTIORHYNCHUS-OVATUS (L)(COLEOPTERA, CURCULIONIDAE), ON YOUNG ORNAMENTAL CONIFER TREES IN SOUTHERN ONTARIO

Field and laboratory studies were undertaken in southern Ontario to ga in bionomical information on the adult strawberry root weevil (Otiorhy nchus ovatus), a pest of ornamental conifer trees in nurseries. Emerge nce of overwintering adults began on 3 June 1991 and lasted 56 days, w ith 50% emerging within 18 days. Adults dispersed less than 5 m in 48 days from a single release point. About 50% of females were fecund. Th e laboratory temperatures at which adults were reared (15, 20, and 25 degrees C) had no significant effect on fecundity (62.3 eggs per femal e) but influenced longevity; adults at 15 degrees C lived longer than at 20 or 25 degrees C. The mean preovipositional and ovipositional per iods were 31.5 and 49.0 days, respectively. Less than 1% of adult weev ils released in the field survived the winter; overwintering, adults l ived 10 months. Egg eclosion occurred 16 days after oviposition with 7 8% of the eggs viable. The significance of these biological observatio ns in the development of management strategies for this pest is discus sed.