Field data revealed that Iphiseiodes quadripilis was significantly more abundant on grapefruit leaves than on sweet orange leaves in contiguous citrus orchards at four sites. Similar results were obtained whether samples were taken from border trees or interior trees. The total numbers of phytoseiids were not significantly different between tree types in most cases. The Texas citrus mite Eutetranychus banksi (Tetranychidae) was the most numerous prey species and was significantly more abundant on sweet orange than on grapefruit. Iphiseiodes quadripilis demonstrated a significant preference for grapefruit leaves over sweet orange leaves in an olfactometer and in contact choice tests with leaf discs in the laboratory. Densities of E. banksi were observed to be lower on grapefruit than on sweet orange in the field, suggesting that better biological control by I. quadripilis was occurring on the former host plants.
Species 1: Acari Phytoseiidae Iphiseiodes quadripilis (shiny button mite)
Species 2: Acari Tetranychidae Eutetranychus banksi (Texas citrus mite)
Keywords: biological control, citrus
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA