Effect of <i>Callophora erythrocephala Meigen</i> puparial size on the ratio of <i>Melittobia acasta Walker</i> (Hymenoptera: Eulophidae)

Abstract

The most important biological control agents which are pro-ovigenic and synovigenic parasitoids usually assess their host critically before laying eggs in the Melittobia acasta Walker, a synovigenic parasitoid of several dipteran species is potentially as agent for the biological control of such nuisance dipteran fly pest as Calliphora and Musca species. A critical requirement before a parasitoid could be deployed for the control of any pest in any pest in a thorough understanding to determine the effect of Calliphora erythrocephala Meigen puparial size on the sex ratio of M. acasta of uniform size (head width=0.360.37mm) were given five puparia of similar age (4872h) from three experimental host size grades for a period of 24h. After oviposition, the parasitised puparia were reared at 25°C for fourteen days and then dissected to count the number of male and female parasitoid pupae. The results show that M. acasta laid a similar proportion of male to female eggs on a large as well as on small hosts. The pattern of sex allocation and its significance in the reproductive biology of the parasitoid is discussed.

Bio-Research Vol. 3(1) 2005: 39-44