SOME EFFECTS OF P³² ON THE DEVELOPMENT OF <i>DROSOPHILA</i>

Abstract

When freshly laid Drosophila eggs were placed in a graded series of P 32 concentrations in the culture media, death of treated individuals occurred most frequently at the end of the larval period and in the pupal stages. No adults emerged from cultures having an initial concentration of 0.65 rutherford (rd.) or higher per ml. food. The calculated concentration of P 32 expected to reduce emergence of adults to 50% is 0.120 rd. per ml. A dosage of 1.30 rd. per ml. prevents transformation of larvae to pupae. Three out of 132 X-chromosomes from males reared in medium having an initial concentration of 0.0325 rd. per ml. carried new recessive lethal "genes".