<p>Laboratory study was carried out to investigate the efficacy of hymenopteran parasitoids, (<em>Dinarmus basalis</em> and <em>Choetospila elegans)</em> parasitization of <em>Callosobruchus maculatus</em> on cowpea (<em>Vigna unguiculata</em>) seeds in the Department of Crop Science, University of Calabar, Nigeria. Treatments were the inoculation of <em>D. basalis</em> (sole), <em>C. elegans</em> (sole), a mixture of <em>D. basalis</em> and <em>C. elegans</em> into infested cowpea seeds and the control which received no parasitoids. The introduction of parasitoids was repeated at 3 d interval, and all treatments were replicated 3 times. Result indicated that early introduction of the parasitoids caused significantly (P ? 0.05) higher mortality of <em>C.maculatus</em> than late introduction. Mix culture of both parasitoids was significantly more efficacious than sole culture. The emergence of each parasitoid and the mortality of <em>C. maculatus</em> in sole culture showed a highly significant (P ? 0.01) positive relationship (r = 0.487) between <em>C. maculatus</em> and <em>D. basalis</em> but non-significant (P ? 0.05) though positive association (r = 0.289) with <em>C. elegans</em>. A multiple regression analysis between <em>C. maculatus </em>mortality and the emergence of the two parasitoids in mix culture also indicated a highly positive significant (P ? 0.01) relationship (R = 0.751, R<sup>2</sup> = 0.564). Pearson Correlation analysis also showed a significant (P ? 0.05) positive association (r = 0.464, and 0.401) between <em>C. maculatus</em> mortality and emergence of <em>C. elegans</em> and <em>D. basalis</em> in mix culture, respectively. However, a non significant (P ? 0.05) negative relationship (r = -0.336) was observed between the two parasitoids in their emergence in mix culture, but <em>D. basalis</em> contributed more to the mortality of <em>C. maculatus</em> than <em>C. elegans</em>. Data from this study showed that <em>D. basalis</em> and <em>C. elegans</em> have potentials to be deployed as biological control entities in the management of <em>C. maculatus</em> as a part of the integrated pest management strategies of storage pests in the tropics.</p>
Dynamics of parasitoid-host interaction: Application of the case of <em>Callosobruchus maculatus</em> (Chrysomelidae) and <em>Dinarmus basalis</em> (Pteromalidae)
