Phenotypic effects of heterozygous,x-rayinduced mutations in Drosophila

Heterozygous mutations produced by 3000 r delay pupation in about 9 percent of larvae of Drosophila melanogaster under nutritional stress and kill approximately 6 percent. The effects are less, though appreciable, when there is excess nutrient; no effects are detectable after o?gonia are irradiated. Irradiated sperm and o?cytes cause detriment, partly via different types of mutations, in approximately equal amounts.