Effects of Temperature and Water Source on Development of Deraeocoris nebulosus (Uhler) (Hemiptera: Miridae), a Predacious Plant Bug1

Abstract

The development of Deraeocoris nebulosus (Uhler) was studied in relation to temperature and to water sources additional to food. Development time for D. nebulosus was linear between 20° and 30°C, allowing the use of a linear equation to calculate degree days. The eggs of D. nebulosus required 111.1 degree days over a threshold of 13.9°C to complete development. Nymphal development for males and females of D. nebulosus was about 1.5 times faster at 25°C than at 20°C, 1.5 times faster at 30°C than at 25°C, and almost 2.5 times faster at 30°C than at 20°C. Males developed 2 d faster than females (protandry) at 20°C, but did not develop faster at the other temperatures. This study provides the first record of temperature-regulated protandry in insects. Nymphs of D. nebulosus required 166.7 degree days over a threshold of 12.7°C for males and 15.2°C for females. Preoviposition period was almost 12 d at 20°C and about 6 d at 25° and 30°C. Water source (free water, sugar water, or sweet potato leaf) did not affect the development of D. nebulosus when fed moth eggs.