抄録
Seasonal occurrence of the sugar cane woolly aphid Ceratovacuna lanigera ZEHNTNER and its predators was monitored in sugar cane fields in the southern part of Okinawa Island, Japan from October 1988 to March 1990. C. lanigera occurred more frequently in summer-planted fields than in ratooned fields. In summer-planted fields, new colonies of C. lanigera were frequently observed in November and December. These colonies gradually increased during winter. The number of infested leaves peaked in April, then decreased abruptly after insecticide spraying in April/May. C. lanigera was usually uncommon in summer, but in those fields where it was abundant various predators attacked the aphid colonies and quickly suppressed its increase.
