Effects of UV-irradiation at Various Wavelengths on Sterilizing Drosophila Embryos: (Drosophila embryo/UV-effects/pole cells/polar plasm/nucleic acids).

Embryos of Drosophila melanogaster at the early intravitelline nuclear multiplication stage were irradiated with UV light at the posterior pole. The sterility and mortality of these embryos were examined in relation to the dose and wavelength of the UV light. Sterility, expressed either as the frequency of pole-cell-deficient embryos, or as the frequency of agametic adults, was found to be dependent on the wavelength of UV light. UV-irradiation at 280 nm was found moot effective in causing sterility on Drosophila embryos. The minimum dose of radiation to give a 100% sterility was 200 J/m at 280 nm, and 400 J/m at 254 nm. In contrast, mortality showed no dependency on the wavelength. The possibility that nucleic acids in the posterior region is a target of 280 nm radiation is discussed.