Midsouth Entomologist
Abstract
We examined the standard metabolic rates of pyrethroid resistant and susceptible German cockroaches, B. germanica. Measurements of CO2 production and O2 consumptions were obtained at 5 to 40 °C at 5 °C intervals using closed-system respirometry. Overall VO2 (ml g-1 h-1) was not significantly different among strains but different strains reacted differently to increasing temperature. Mean cockroach body mass differed significantly among strains and VO2 (ml g-1 h-1) scaled with temperature and mass in all strains. We used data at 25 °C to examine the effect of mass on the rate of oxygen consumption. Mass specific VO2 (ml g--1 h-1) at 25 °C was 0.5170 ± 0.13 and 0.6931 ± 0.059 for the susceptible strains (black and ACY, respectively) and 0.7714 ± 0.059 for the resistant strain. The relationship between metabolic rate and body mass yielded an exponent of 0.78 for the resistant strain and 0.81 and 0.89 for the susceptible strains (black and ACY, respectively), and are similar to those of other cockroaches. Measurement of O2 and CO2 made possible the examination of temperature and mass effects on respiratory quotient (RQ). Respiratory quotient increased with temperature up to about 25 °C, declining thereafter in all the strains; however there were differences in response among strains. Several equations relating temperature and mass to VO2 are presented. The supercooling point of the resistant strain was significantly greater than those of the ACY and black susceptible strains.
Recommended Citation
Dingha, B. N.; Appel, A. G.; and Vogt, J. T.
(2009)
"Effects of Temperature on the Metabolic Rates of Insecticide Resistant and Susceptible German Cockroaches, Blattella germanica (L.) (Dictyoptera: Blattellidae),"
Midsouth Entomologist: Vol. 2:
No.
1, Article 3.
Available at:
https://scholarsjunction.msstate.edu/midsouthent/vol2/iss1/3