Aerial dispersal of citrus rust mite, Phyllocoptruta oleivora (Ashmead), in
central Florida showed a diel periodicity peaking between late morning and
early afternoon. The abiotic factors that best described the dispersal pat
tern were solar radiation, time, and leaf wetness; whereas wind speed, humi
dity, temperature, and rainfall had minimal effect. The longevity of adult
mites removed from fruit was inversely related to constant temperatures bet
ween 25 and 35 degreesC. The longevity of mites removed from fruit at 2-h i
ntervals between 0700 and 1300 hours and exposed to ambient temperature and
humidity outdoors was inversely related to the time of removal from the ho
st. There was a linear relationship between the number of mites captured in
traps and population density on fruit. Mites left fruit harboring extremel
y low populations and some fruit supporting dense populations yielded hundr
eds of dispersing mites per day. Mites were readily carried on air currents
between adjacent citrus groves. Nearly all of the mites captured in disper
sal traps were adult females, and were found in greater proportions in trap
s than would be expected from the sex ratio of mites on fruit. Studies usin
g isolated fruit in the laboratory showed that a single virgin or inseminat
ed female could initiate a local population through oedipal mating and sibm
ating. The data are discussed in relation to the selective forces that may
shape the dispersal behavior of citrus rust mite and to the potential impac
t of aerial dispersal on mite management and the development of acaricide r
esistance.