Biological and biochemical parameters of a flightless strain of Harmonia axyridis, fed on a pork liver-based artificial diet and on Ephestia kuehniella eggs as controls, were compared. The diet-grown larvae showed a significantly longer developmental time and a lower adult emergence rate compared to control larvae. The weights of the newly emerged adults were significantly higher for adults fed E. kuehniella eggs during their larval stages than fed the artificial diet. In contrast, larval food source had no effect on the duration of the pre-oviposition period or adult longevity. For adults fed on E. kuehniella eggs as larvae, a significantly longer pre-oviposition period, lower daily weight gain and fecundity were found for the diet-fed females compared to those fed on E. kuehniella eggs throughout the life span. The adult food source had no significant effect on longevity and fertility. Lower amino acid and fatty acid contents (in particular C16:1 and C18:3n-3) were found for the prepupae and newly emerged females obtained from diet-reared larvae compared to controls. Deficiencies in fatty acids C16:1 and C18:3n-3 were also observed in females obtained from E. kuehniella egg-reared larvae and fed on diet from adult emergence. The analyses of the foods showed deficiencies in artificial diet, especially for some amino and fatty acids. The results suggest a non-optimal composition of the artificial diet and some possibilities for its improvement. However, this polyphagous predator could be reared from first instar larvae to fully reproductive adults on a pork liver-based artificial diet.

Quantitative and qualitative parameters of Exorista larvarum (L.) (Diptera: Tachinidae) reared on two insect‐material‐free artificial media and in the factitious host Galleria mellonella L. (Lepidoptera: Pyralidae) were compared. Significantly higher puparial yields and weights were obtained in both a milk‐based and a veal homogenate‐based medium than in the factitious host. Longevity and parasitization rates were not different between the in vitro‐ and in vivo‐reared flies. Despite the greater puparial weight of the veal medium‐reared E. larvarum females, the number of eggs laid by these females on host larvae was not higher than that of females reared under the other two rearing conditions. Moreover, in a complementary experiment, with homogeneous puparial weights of milk medium‐ and host‐reared females, the former oviposited fewer eggs. Hence, puparial weight alone is not a reliable quality parameter for E. larvarum reared on artificial media. Lower amino acid content, with a deficiency in aromatic amino acids and an excess in proline, was found for in vitro third instar parasitoid larvae reared on both media compared to the in vivo‐reared ones. These results suggest a correlation between the amino acid deficiency and imbalance of medium‐reared larvae and the lower number of eggs laid by the females obtained.

Abstract. We describe here the in vitro rearing of Anagrus breviphragma Soyka, an egg parasitoid of Cicadella viridis (Linnaeus), from the second instar larva to the adult stage. Three media, containing mainly either a commercial tissue culture medium (IPL-41), skimmed milk or veal homogenate, were tested. Larval development occurred on all the diets but few larvae reached the pupal stage on the diets containing skimmed milk or veal homogenate. On the tissue culture medium, pharate adults, albeit malformed, developed. Supplementing the tissue culture medium-based diet with chicken egg yolk alone, or combined with yeast extract, further improved parasitoid development. The addition of both egg yolk and yeast extract resulted in twelve out of twenty larvae reaching the adult stage, of which only four females emerged.

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