Thermal Death of Third Instars of the Caribbean Fruit Fly (Diptera: Tephritidae) Treated in Different Substrates

Eight substrates (air, water, artificial diet, and fruit pulp blends of guava, grapefruit, orange, mango, and orange) were examined for their impact on survival of third-instar Caribbean fruit fly, Anastrepha suspensa (Loew), exposed to 40°C for 67 min. Survival was the greatest for larvae heated in air (92.9 ± 1.1%) and lowest in water (12.1 ± 1.6%). Mortality was intermediate to high and similar among larvae heated in the fruit blends and artificial rearing diet. Percentage water and oxygen of each substrate, pH, and specific gravity did not affect larval mortality, but the type of substrate (air, water, fruit pulp blend) was significant. The upper thermal limits of a quarantine treatment can be screened for all pest life stages by testing time-temperature regimes using air as a substrate.