EFFECTS OF HEAVY-METALS AND FLUORINE ON PHAGOCYTOSIS AND PHENOLOXIDASE ACTIVITY IN MAMESTRA-BRASSICAE (LEPIDOPTERA, NOCTUIDAE)

Phagocytic response to injected iron saccharate and yeast cells (heat- killed Saccharomyces cerevisiae or viable Candida tropicalis) and haem olymph phenoloxidase (PO) activity were studied im Mamestra brassicae larvae fed on diets contaminated by copper, lead, cadmium of fluorine ions. In copper-stressed larvae, increased and reduced percentage of p lasmatocytes and granular cells, respectively, and a reduced phagocyto sis of iron saccharate were found. Cadmium- and fluorine-treatment red uced phagocytosis of S. cerevisiae. Cadmium showed a stimulatory effec t, copper an inhibitory effect on phagocytosis of C. tropicalis. PO ac tivity was reduced by all toxicants, in copper-stressed larvae it reac hed only 22% of the activity in the control.