Pupal Development Rate of Heliothis Armiger (Hubner) (Lepidoptera: Noctuidae) Under Constant and Alternating Temperatures.

Non‐diapausing and post‐diapausing pupae of Heliothis armiger (Hübner) were subjected to alternating and constant temperatures, and the number of days to adult emergence was recorded. For both kinds of pupae alternating temperatures of wide amplitude accelerated development rate in comparison with the relevant mean constant temperature. Non‐linearity of the developmental velocity curve at temperature extremes is discussed as one possible explanation for acceleration in development. The implication of earlier emergence under fluctuating temperatures is considered in relation to computer models for predicting emergence of H. armiger in the field.