The Significance and Thermodynamics of Fluctuating Versus Static Thermal Environments on Heliothis zea Egg Development Rates 1

Abstract

Egg development of Heliothis zea (Boddie) was studied under various static and fluctuating environmental regimes. Two computer-controlled environmental chambers were programmed to fluctuate temperatures through diurnal sinusoids of ±5°F (2.8°C) to ±20°F (11.1°C) using the same mean temperatures as regimes in statically controlled environmental chambers. The heat-units concept of development proved not to apply to bollworm egg development. In its stead, a hypothesis is formulated based on the egg-development curve measured in static thermal conditions.