Three different nee mpreparations were used in our experiments: neem kernel water extract (NKWE), NeemAzal-T/SÒ(NA) of Trifolio M-Company D-35633 (Lahnau, Germany) and neem oil (NO) with the emulgator RimulganÒ of Niem-Handel, D-64347 (Griesheim, Germany). The experiments with NKWE were conducted with cabbage (Brassica oleraceavar.medullosa). For the studies with the other two preparations oats were used (Avena sativa). Some details of the preparations and the experiments are indicated in table 1.Three predator species were tested as larvae (LI toLIV ¼ first to fourth instar larvae): (1) Episyrphus balteatus (DeGeer) (Dipt., Syrphidae), LI with NKWE. (2) Coccinella septempunctata, with all preparations, NKWE with LI, the other two preparations with LI and LII. (3) Chrysoperla carnea, LI/LII, with NA and NO. The syrphid and coccinellid predators were reared in the institute at long day (16.00 : 08.00 hours, L : D) conditions and 5000–20 000 lx, in cages of 50·50·50 cm, with two sides of fine gauze, and two sides and lid of glass. The syrphids were supplied with pollen of sunflower, wild flowers of the season, water, and cabbage plants with aphids for oviposition; coccinellids received cabbage plants with aphids. Eggs of C. carnea were supplied by the Federal Institute for Biological Control at Darmstadt, Germany. During the experiments, neem-treated aphids were offered to the predator larvae as food, when the spray had dried. The leaves the aphids were sucking on had been sprayed simultaneously. Treated aphids were partly offered for1 day only, but mostly for 2 days as indicated in the text. When untreated aphids were offered, simultaneously new,untreated plants were placed with them. Aphids treated with water served as control. Sprayings were conducted with amotor-driven laboratory equipment producing fine droplets and spraying 10 ml per plant per pot (equal to 600 l/ha), from a distance of 20 cm. The rate of application (g/haAzaA) is shown in table 1. In some experiments with NKWE, the extract was applied to the soil, so that plants could take it up by the roots (Lowery, 1992; Nisbetet al.,1996). Four days after this treatment, assuming that neem reached the phloem, experiments started. All experiments were run with 3–5 predator larvae per unit (pot per cage),with 10 replicates.In the case of C. septempunctataand C. carnea also eggs were sprayed with the nee mpreparations to measure the rate of hatching. For testing NKWE, 300–780 eggs of C. septempunctata were taken, for NA and NO 50 eggs each, of C. septempunctata and C. carnea.One parasitoid species was tested during the experiments with NKWE: Diaeretiella rapae (McIntosh) (Hym., Aphidii-dae). In experiments with NKWE, C. septempunctata and E. balteatus larvae were tested in plastic cages with a lid of fine gauze. Cages measured 20·10·10 cm for C. septempunc-tata, and 10·10·5 cm for E. balteatus, and contained the plant material (cabbage leaf discs) with aphids. In the parasitoid D. rapae, potted cabbage plants with aphids were placed in round plastic cages (diameter 20 cm, height 40 cm, lidoffinegauze). Incase of the parasitoid (D. rapae), because of the possible repellent effect of neem (Schmutterer, 1995), 10 female parasitoids were caged together with 100 aphids and allowed to oviposit for 24 h prior to their removal, and subsequent treatment with NKWE (topically on the aphidsoras soil treatment). The female parasitoids were taken from an own rearing cage, and were not older than 24 h. In the parasitoid, the performance in the generations F1 and F2 was also studied. In experiments with NA and NO and predators (C. septem-punctataand C. carnea), five at seedlings were grown in pots (diameter 9 cm) and inoculated with aphids. The pots were covered by a plastic beaker, with two gauze-covered openings for ventilation. After treatment of the aphids, five predator larvae (LI or LII) were placed on the plants, and left for 2 days with the treated aphids. After 2 days, untreated aphids were offered, together with new plants.