Insecticidal Property of Black Seed (Nigella sativa) Powder as an Eco-friendly Management of Skin Beetle Dermestes maculatus (Coleoptera: Dermestidae) in Atlantic Codfish Gadus morhua (Gadiformes: Gadidae)

The bio-pesticidal potential of Nigella sativa seed powder in the management of Dermestes maculatus in codfish (Gadus morhua) was evaluated in the laboratory. D. maculatus beetles were obtained from naturally infested smoked fish, cultured at ambient temperature for the establishment of new stock and same age adults. Purchased N. sativa seeds were ground into fine powder, weighed at 0.4 g, 0.8 g, 1.2 g, 1.6 g and 2.0 g for use in the bioassay. The treatments were separately added into 40 g codfish kept in Kilner jar into which two sexed pairs of D. maculatus were introduced and observed. From the results, the number of the developmental stages (larvae, pupae and adults) of D. maculatus in codfish treated with N. sativa seed powder was inversely proportional to the concentration of the seed powder. Thus, an increase in the concentration of N. sativa powder generated reduction in the mean number of D. maculatus progeny found in the codfish after 35 days as follows: at 0.4 g, progeny development was (103.50, 7.75, 2.50) and 77.00, 8.25 and 1.00 at 2.0 g respectively for larva, pupa and adult stages. Percentage protection conferred by the botanical on D. maculatus showed that all the doses applied were effective. Corrected mortality of D. maculatus adults after 45 days of exposure to the different doses of N. sativa treatments also increased with an increase in concentration of N. sativa from 0.4 g to 2.0 g. Frass weight generated by D. maculatus activity in codfish treated with N. sativa powder was high in codfish treated at 1.6 g. Finally, N. sativa characterized both qualitatively and quantitatively for phytochemicals, proved the secondary metabolites with bio-pesticide potentials against D. maculatus such as phenols, Alkaloid, flavonoid, terpenoid, saponin, tannin, Cardiac glycoside, anthraquinone, steroid and oxalate in different proportion, therefore, should be utilized in Integrated Pest Management program of stored codfish.