Pupation and emergence of blueberry gall midge, Dasineura oxycoccana (Diptera: Cecidomyiidae), under varying temperature conditions

Abstract

Temperature-based development models have been used in pest management for many years to predict emergence and other life history events of insect pests. Blueberry gall midge, Dasineura oxycoccana (Johnson), is an early-season pest of rabbiteye blueberries, Vaccinium virgatum Aiton, in Florida. The ability to predict emergence of adults at the beginning of the season would improve monitoring and control activities. Blueberry gall midge larvae were collected from an organic blueberry farm in Gainesville, FL from Jan through Mar in 2008 and 2009. Late third instars were reared to adults in either 5-mL vials or 947-mL cups with soil substrate. The duration of the pupal stage was determined under 6 constant temperatures: 10, 15, 20, 25, 30, and 35°C. More midges survived to adult emergence in the 5-mL vials than the large cups. The developmental threshold was estimated with linear and nonlinear regression models. Both models fit the data well, but the nonlinear model was limited due to the few data points at the extreme high and low temperatures. Based upon the linear model and data from the 5-mL vials, the developmental threshold for pupation was estimated as 9.8°C and the thermal constant as 134 degree-days. These experiments provide useful information on the biology of blueberry gall midge, but estimates of the thermal requirements for the other life stages will be needed before it will be possible to forecast blueberry gall midge infestations.