Aerial Dispersal of Citrus Rust Mite (Acari: Eriophyidae) from Florida Citrus Groves

Abstract

The aerial dispersal of citrus rust mite, Phyllocoptruta oleivora (Ashmead), from Florida citrus groves was monitored throughout the 1995 growing season, using silicone grease-coated traps. Trap-catch was not affected by trap elevation, nor was there a consistent effect of wind direction on catch among 3 groves. Significantly more mites were captured in vertically oriented than in slanted traps in 2 of the 3 groves. The seasonal pattern of dispersal showed marked and coincident peaks from mid-September through mid-October at the 3 sites. There was a strong linear relationship between trap-catch and population density on fruit at 2 of 3 sites and when data from the 3 sites were combined. Dispersing mites infected with the entomopathogenic fungus, Hirsutella thompsonii Fisher, were captured in traps at the 3 groves, and the peak capture of infected mites generally coincided with the peak and decline of trap-catch. Mites were captured up to 135 m from an infested grove, and the mean ± SD dispersal distance under the prevailing conditions was 10.95 ± 20.34 m. The majority of mites captured during 1-h trapping intervals were alive. These results are discussed in relation to the population dynamics of citrus rust mite and to current trends in pest management practices in Florida citrus.