Relationship Between Temperature and Development of Lariophagus distinguendus (Hymenoptera: Pteromalidae), an Ectoparasitoid of Sitophilus oryzae (Coleoptera: Curculionidae)

Abstract

Development of Lariophagus distinguendus (Förster) parasitizing fourth instars of Sitophilus oryzae (L.) was studied in relation to temperature. As the temperature increased from 20° to 32°C, total developmental period of the female and male parasitoids decreased from 31.0 ± 1.02 to 14.2 ± 0.7 d and from 28.0 ± 1.0 to 13.8 ± 0.8 d, respectively. The developmental period at 34°C was similar to that at 32°C. Complete development at 18°C was significantly inhibited. Males developed faster than females. The relationship was described fairly well by a combination model; lower and upper thresholds for complete development of female and male were estimated to be 15.1° and 37.2°C, and 15.2° and 38.7°C, respectively.