Are Dried and Powdered Moringa oleifera Lam. Leaves Susceptible to Moths That Feed on Stored Products?

Abstract

The leaves of Moringa oleifera are increasingly used as a food supplement in several countries due to their nutritional composition, which is rich in protein, vitamins, and mineral salts. Foodstuffs can be damaged by several pests when stored in environments with temperatures that are favorable to insect development; therefore, the susceptibility of M. oleifera leaves to attacks of moths that feed on stored products was tested. Tests were carried out on Pyralid Cadra cautella, Corcyra cephalonica, and Plodia interpunctella, as well as Geometrid Idaea inquinata, which were reared on dried whole or powdered M. oleifera leaves, an artificial diet, or an artificial diet supplemented with dried or powdered leaves. The numbers of adults and the development periods with the different diets were recorded. M. oleifera leaves were unsuitable as a rearing medium for all of the species except I. inquinata, although only a few individuals of this species reached the adult stage. The use of an artificial diet of which one-quarter consisted of dried and powdered leaves did not affect the number of progeny or on the biological cycle, showing that the effect was due to the nutritional composition, as well as to the toxic effect. The storage of M. oleifera as powdered leaves is recommended in order to preserve the nutritional characteristics and avoid damage caused by moth larvae.