Monitoring and phenology of thrips in southern highbush blueberries

Flower thrips damage floral tissues and reduce yield in southern highbush blueberries, but information on species complex and phenology is limited. During 2004 and 2005, we studied thrips species complex and phenology on two 1-ha commercial southern highbush blueberry farms. White sticky traps and blueberry flowers were used as our sampling units. Ten traps were placed randomly ~31 m apart throughout each 1-ha farm located in south-central and north-central Florida, respectively. Traps were collected weekly from flower opening to fruit set and thrips were removed and individually slide mounted for identification. Similarly, five flower-clusters (about five flowers per cluster) were collected weekly from the same bushes where the traps were deployed. The thrips were removed from the flowers and preserved in 50% alcohol before being slide-mounted for identification. Voucher specimens from traps and flowers were sent to the Florida State Collection of Arthropods (FSCA) in Gainesville, FL. Among the thrips species recorded at both sites, the Florida flower thrips [ Frankliniella bispinosa (Morgan)] was the most commonly encountered species, accounting for >65% of the thrips in flowers and >83% of the thrips on sticky traps. Other species recorded included F. fusca , F. occidentalis, and Thrips hawaiiensis, which individual species accounted for less than 13% of the thrips found in flowers and on sticky cards. Sporadic catches (fewer than two specimens) included Haplothrips victoriensis , F. kelliae , and F. schultzei . Overall thrips abundance was highly correlated with flower development.