Wednesday, December 12, 2001 -

Calorespirometry to determine the effects of temperature on the metabolic efficiency of Harmonia axyridis (Col.: Coccinellidae) larvae

E. BARÇIN Acar1, Bruce N. Smith2, Lee D. Hansen3, and Gary M. Booth1. (1) Brigham Young University, Department of Zoology, 574 WIDB, Provo, UT, (2) Brigham Young University, Department of Botany and Range Science, 687 WIDB, Provo, UT, (3) Brigham Young University, Department of Chemistry and Biochemistry, E-113 BNSN, Provo, UT

Differentiating temperature responses of predatory insects is an important part of understanding their life history, and is often necessary for predicting their potential as bio-control agents of herbivorous insects. To illustrate the power of current methods of calorespirometry in determining the response of energy metabolism to environmental variables, we used isothermal calorimetry to measure metabolic heat and CO2 production rates of immature multicolored Asian lady beetles (Harmonia axyridis Pallas) as a function of temperature. Metabolic heat rates (Rq) and respiration rates (RCO2) of immature, multicolored Asian lady beetle, were measured in isothermal calorimeters at 5°C intervals from 0 to 40°C. Anabolic rates and energy use efficiencies were calculated as functions of temperature from the calorespirometric data. The beetles are predicted to be most successful in the temperature range from 10 to 35°C, with an optimum from 15 to 25°C. These conclusions agree with results from behavioral studies and the results demonstrate the energy use efficiency of immature lady beetles changes continuously with temperature. Calorespirometry is fast and less labor intensive and provides efficient determination of suitable temperature ranges required for optimum biological control success for beneficial insects.

Species 1: Coleoptera Coccinellidae Harmonia axyridis (multicolored Asian lady beetle)
Keywords: isothermal calorimetry, temperature dependence

The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA