The Influence of Temperature on Longevity and Fecundity in the Bug Lygus hesperus (Hemiptera: Miridae)

Abstract

Age-specific fecundity and mortality schedules were determined for Lygus hesperus Knight adults at constant, alternating, and variable temperatures. Constant temperatures ranged between 55 and 100°F. In the alternating temperatures, the bugs were alternated on a 3-day schedule between a constant high and a constant low temperature, while under the variable temperature regimes, the bugs were exposed to daily fluctuations of 55–95°F or 55–100°F. At 55°F, L. hesperus produced 1 egg each 3rd day and the mean female longevity was 120 days and maximum longevity was 200 days. Temperatures above 90°F were detrimental; no eggs were produced at 100°F. Life table calculations revealed that constant 90°F or alternating temperatures of 80–90°F yielded the maximum potential rate of population increase. Egg hatch was inversely related to temperature; only 6% of eggs laid at 95°F hatched. The rate of egg production at either of the alternating temperatures was the same as that which occurred when the bugs were exposed to similar constant temperatures.