Ecological interactions of Harmonia axyridis and Aphis glycines in Ontario agroecosystems
The multicoloured Asian ladybeetle 'Harmonia axyridis' Pallas (Coleoptera: Coccinellidae) is an occasional pest of wine grapes in the Niagara Peninsula region of southern Ontario. Outbreaks of 'H. axyridis' appear to correlate with outbreaks of an introduced soybean pest, 'Aphis glycines' Matsumura (Hemiptera: Aphididae). This thesis examines the dynamics of these two species in Niagara area soybean fields, develops a model for predicting early season development events of ' A. glycines,' and examines the visual and olfactory cues associated with 'A. glycines' and its hosts employed by foracing adults of 'H. axyridis.' Interactions between the two species in hedgerow ecosystems in spring and autumn appear to be integral to understand the relationship of these two species and to predict economic infestations of both ' A. glycines' and 'H. axyridis.' Recommendations are made for the development of an integrated pest management program for ' H. axyridis.'