OVERWINTERING AND COLD TOLERANCE OF BEMISIA-ARGENTIFOLII (HOMOPTERA, ALEYRODIDAE) IN COASTAL SOUTH-CAROLINA

Populations of Bemisia argentifolii Bellows and Perring in the Charles ton, SC area declined sharply during December and remained low through March and April in a two-year study (1991-92). Populations of this wh itefly increased slowly during spring with highest populations on coll ard (Brassica) and potato. Infestations of B. argentifolii were presen t in 13 of 14 greenhouses at 10 commercial nurseries that were monitor ed. Eggs were more cold-tolerant than adults and nymphs, respectively, at temperatures of -2 degrees, -6 degrees, and -10 degrees C.