Effect of temperatures and diets on the life cycle of Ephestia elutella

Ephestia elutella (Hübner) (Lepidoptera: Pyralidae), an omnivorous pest
with a wide range of hosts, is responsible for the damage and loss of many
stored commodities. However, the parasitoid wasp Habrobracon hebetor (Say)
(Hymenoptera: Braconidae) utilizes 5th instar E. elutella larvae to breed.
In order to support the large-scale production of E. elutella for research
and parasitoid rearing, we explored the effects of diet (artificial diet
and tobacco) on the mortality, developmental duration, adult longevity,
fecundity, and population parameters of E. elutella reared at 19, 22, 25,
28, and 31˚C using age-stage, two-sex life tables. Increasing the
temperature from 19 to 31˚C significantly affected the stage-specific
mortality, reproductive parameters, and population parameters of E.
elutella. Specifically, both developmental duration and adult longevity
decreased with increasing temperature. For both diets, pre-adult mortality
was lowest at 25˚C, but was lower overall in populations fed an artificial
diet. The developmental duration, adult longevity, and mean generation
time (T) were significantly lower in populations fed an artificial diet,
whereas the intrinsic rate of increase (r) and finite rate of increase (λ)
were significantly lower in populations fed tobacco leaves. Temperature
appears to have a significant effect on the development and reproduction
of E. elutella, and a combination of 25˚C and artificial diet may be the
most conducive to large-scale breeding. This study provides a theoretical
basis for the mass rearing of E. elutella to support pest control
applications in tobacco warehouses.