INFLUENCE OF TEMPERATURE AND LARVAL DENSITY ON FLIGHT PERFORMANCE OF DIABROTICA VIRGIFERA VIRGIFERA LECONTE (COLEOPTERA: CHRYSOMELIDAE)

Abstract

AbstractThe influence of temperature and larval density on the flight performance of Diabrotica virgifera virgifera LeConte was quantified in the laboratory using a tethered flight system. Temperature had a significant influence on trivial flight performance in males and in both young (5 day) and older (25 day) females. The proportion of beetles undertaking trivial flight, and trivial flight duration and frequency peaked at temperatures around 20–25°C. Generally, males were more active than females at lower temperatures. Female beetles did not display sustained flight behavior at 15 or 35°C and males did not undertake sustained flight at 30 or 35°C. Sustained flight duration was unaffected by temperature. Rearing larvae at different densities influenced adult size but had only subtle effects on adult flight performance. Larval density significantly influenced trivial flight duration and frequency of older females and flight frequency of males but had no effect on young females. In general, trivial flight performance peaked when larvae were reared at moderate densities (500–750 per primary rearing container). In young females the propensity for sustained flight, but not flight duration, declined with increasing larval density.