Artificial diets for the rearing of Rhynchophorus ferrugineus Olivier

Laboratory rearing of the red palm weevil Rhynchophorus ferrugineus Olivier (RPW) on natural or semi-artificial diets is a problem outside of the RPW's native countries because it may be difficult to find some dietary components and/or their preparation is too expensive or laborious. Therefore, we carried out studies on alternative ingredients to prepare more practical and economical feeding substrata for weevil rearing. The life cycle parameters of RPW were tested in the laboratory using the artificial diets of other authors but with the replacement of some components, i.e. a mixture of unidentified cereals with buckwheat alone (Diet 1) or molasses with polyfloral honey (Diet 2). Further tests were carried out on alternative diets, respectively composed of honey, dried coconut cake and oat (Diet3) or commercial apple mousse (Diet 4). Growth time, weight and mortality of R. ferrugineus larvae, and female fecundity were significantly different among Diet 1, Diet 2 and Diet 4, while the pupal period and mortality, adult female longevity and egg fertility did not differ. Diet 3 appeared unsuitable for R. ferrugineus larval survival. Diet 1 was most suitable for pre-imaginal development and female fecundity.