Heavy metal concentrations in males and females of three pine diprionids (Hymenoptera)

Heavy metal concentrations (Cu, Fe, Ni, Cd) in the cocoons of three gregarious pine diprionids, Gilpinia socia, Diprion pini and Neodiprion sertifer, were compared between the species and sexes. The sawflies were reared in the laboratory in colonies from the first ins tar larvae, being fed on Scots pine (Pinus sylvestris) needles collected from a heavily polluted or a relatively unpolluted site . The levels of copper, iron and nickel were two to three times as high inN. serttfer as in the two other species. Cadmium showed bioaccumulation in all three species. InN. sertifer and G. socia reared on polluted needles, the metal concentrations were higher in males than in females.