Studies on Apanteles litae var. operculellae, a Parasite of the Diamond‐back Moth, Plutella xylostella in Egypt

Abstract

AbstractApanteles litae var. operculellae was reared in the laboratory on 2nd instar larvae of Plutella xylostella. The incubation period of the egg was 44 hours at 25 °C and 26 hours at 30°C. The larval stage (3 instars) lasted 6.7 and 5.6 days, the pre‐pupa lasted 24 and 15 hours, the pupa lasted 4.7 and 3.8 days at 25° and 30°C, respectively. The total developmental period of the parasite (from egg to adult) was 14.5 days at 25°C and 11.1 days at 30°C. Sex ratio in A. litae var. operculellae was found to be 1 ♂: 0,83 ♀ in nature and 1 ♂: 0.80 ♀ in the laboratory. Adult females, fed on honey, lived an average of 15.9 and 11.6 days at 25° and 30°C, respectively. The respective figures for males were 14.6 and 6.2 days. – Percentages of parasitism by A. litae var. operculellae in P. xylostella larvae collected from cabbage fields ranged between 0 and 13.7 in Kalubyia Governorate (during May 1981–May 1982) and between 0 and 9.8 in Fayioum Governorate (during July–December 1982).