Influence of substrates on the rearing success of Rhynchophorus phoenicis (Fabricius)

Entomophagy (consumption of insects) is more and more regarded as a possibility to solve food problems of deficiencies or malnutrition. Our objective was to analyze the possibility of rearing the Rhynchophorus phoenicis weevil on side products resulting from agriculture in order to improve its availability at an acceptable cost by the local populations. All experiments were done under basic local conditions and using local products. To this end, we carried out the breeding of R. phoenicis on five types of substrates (old and young palm trunk split in two parts and reassembled or not, sugar canes and two artificial diets) by using either eggs, or first stage larvae to start the production. The young palm trunk gave a much better production when not split, with shorter development duration (15 days against at least 35 days) and heavier last stage larvae (6, 95 g vs 3.4g) on this substrate than on all the others. However, pieces of sugar cane and artificial diet based on plantain-sweet potato pasta added with cowpea gave encouraging results. Larval infestation worked better than eggs infestation. This work underlined the potential of R. phoenicis rearing under the conditions of poor developing countries.