Accumulation and distribution of heavy metal Zn~(2+) in two successive generations black soldier fly Hermetia illucens L.(Dipetra:Stratiomyidae)

Artificial diets added with different concentrations of Zn2+(75,150,300,600,1 200 mg/kg) were fed on black soldier fly Hermetia illucens L.larvae for 2 generations,and contents of Zn2+ accumulation in different developmental stages of H.illucens and distribution in different tissues of the 5th instar larvae were detected.Results showed that excessive Zn2+ accumulate in the 6th instar larvae,pupae and adults,and the order of Zn2+ contents in different stages is 6 instar larvae adults pupae.However,no significant difference is occurred in the different developmental stages' H.illucens from the same generation.At the same time,Zn2+contents from ones stressed with high-levels of Zn2+ in the 2nd generation are significantly higher than those in the 1st generation.Zn2+ accumulate in epidermis,fat body and midgut of the 5th instar larvae.In the 2 successive generations,Zn2+ content in different tissues is in the order of midgut fat body epidermis,and the Zn2+ contents in 2nd generation are all significantly higher than those in the 1st generation.Furthermore,Zn2+ contents in epidermis and fat body of the 2nd generation are significantly higher than those in the 1st generation under treatment with 300 mg/kg Zn2+.Significantly higher Zn2+ contents are found in midgut of 600 and 1 200 mg/kg Zn2+ stressed larvae from the 2nd generation when comparing to the 1st generation.