Apoanagyrus (Epidinocarsis) lopezi (De Santis) (Hymenoptera: Encyrtidae) is a solitary parasitoid indigenous to South America, that was introduced to subsaharan Africa in 1981 as a biological control agent against the cassava mealybug Phenacoccus manihoti Matile-Ferrero (Hemiptera; Pseudococcidae), a pest of cassava, Manihot esculenta Crantz, (Euphorbiaceae). These cassava-mealybug and mealybug-parasitoid systems have been studied extensively, both in the laboratory and under field conditions (Fabres, 1981; Lohr et al., 1988; Le Ru & Tertuliano, 1993). Laboratory evaluations of cassava antibiosis resistance,made by estimating the intrinsic capacity for increase rc, showed that the host plant has an important effect on the multiplying capacity of the mealybug (Tertuliano et al., 1993). Data are still lacking on tritrophic aspects of cassava mealybugs and there is no information on interactions between resistant cassava cultivars and A. lopezi. We conducted laboratory experiments to investigate the influence of four host plants previously characterized by different resistance levels of antibiosis to P. manihoti on the oviposition pattern, longevity, fecundity, survival and development time of A. lopezi. These are five important qualities of a parasitoid that influence its efficiency.