Parasitism potential of four Moroccan local parasitoids species against three invasive scale pest species of agricultural importance.

The recent introduction of new pest species in Morocco and other Mediterranean countries has caused serious problems for many crops. Among the newly introduced pests in Morocco, we have found the scale insects Dactylopius opuntiae (Cockerell) (Hemiptera: Dactylopiidae), Phenacoccus solenopsis (Tinsley), and Phenacoccus peruvianus (Granara de Willink & Szumik) (Hemiptera: Pseudococcidae). To control these scale pests, the parasitism potential of four parasitoid species: Aprostocetus mymaridis (Eulophidae: Hymenoptera), Anagyrus aligarhensis, Anagyrus sp., and Leptomastix epona (Encyrtidae: Hymenoptera) were investigated under laboratory (at 26 ± 2 °C, 60 ± 10% RH) and field conditions. Under laboratory conditions, the experiments were conducted in no choice feeding tests (only third nymphal instars or pre-ovipositing adult females of each scale pest were offered at a time) and choice feeding tests (third nymphal instars and pre-ovipositing adult females were offered simultaneously). We observed that none of the parasitoids tested parasitized D. opuntiae. In both laboratory experimental tests (no choice and free choice tests), A. mymaridis parasitized the highest mean number of third instar nymph and adult female of P. solenopsis (16.90–25.10, and 27.70–29.60, respectively), and L. epona found parasitized the highest mean number of P. peruvianus third instar nymph and adult female (17.70–19.90, and 20.10–24.10, respectively). Aprostocetus mymaridis was found practically suitable for the biological control program of P. solenopsis as they showed a higher level of parasitization under laboratory under field conditions (63.34%). Leptomastix epona seems to be the most successful parasitoid against P. peruvianus under field conditions (67.00%) compared to the other parasitoids tested. [ABSTRACT FROM AUTHOR]