By analyzing changes in the functional activity of the polytene chromosomes of the chironomids the reaction of genetic material under the action of the extract of Sedum telephium L. and dioxydine was ihvestigated. It is established that dioxydine in the acute phase improves the functional activity of polytene chromosomes stronger than the extract of Sedum: the values of the coefficient ring of Balbiani (has also increased in control – 1.87, under the action of dioxydine – 2.15, under the action of extracts of Sedum telephium L.