A Biological Study of the Parasitoid Habrobracon hebetor, its Relationship with the Indian Meal Moth, Plodia interpunctella, and the Effect of Rearing Containers’ Size on the Parasitoid Offspring Generation Under Laboratory Conditions

Abstract

A series of laboratory experiments were conducted on the parasitoid wasp Habrobracon hebetor Say (Hh), aiming to enhance its productivity for potential use in biological control against the Indian meal moth Plodia interpunctella Hübner (Pi), which is a known host under both field and storage conditions. The study investigated methods of rearing and mass production of the parasitoid wasp Hh on Pi larvae as hosts, using different host and parasitoid densities in various rearing container sizes. In the first experiment, several parasitoid densities were tested (2, 4, 6, 8, and 10 mating pairs), at a fixed host number of 50 larvae. The results obtained indicated that the optimal density was 8 mating pairs, yielding the highest number of adult offspring of 184 individuals. The second experiment used varying host densities of 10, 20, 30, 40 and 50 larvae of P. interpunctella, with a fixed parasitoid density of 2 mating pairs. The highest adult emergence (140 individuals) occurred at the host density of 50 larvae. In the third experiment, a fixed parasitoid density of 2 pairs and 50 host larvae was used to study the optimal size of rearing containers, which included volumes of 250, 500 and 1000 ml. Results showed that the 250 ml container yielded the highest number of adults (132.4 individuals). All experiments confirmed that there was no significant effect of the tested factors on the sex ratio of the parasitoid wasp Hh.

Keywords:

Storage pests, Indian meal moth, Plodia interpunctella (Hübner), parasitoid wasp Habrobracon hebetor Say.