[A comparative study of the DNA structural damages and synthesis in embryos of the silkworm Bombyx mori irradiated with gamma rays at different developmental stages].

Studies have been made on formation and reparation of apurine-apyrimidine (AP) regions, monothread DNA ruptures, as well as on inhibition and recovery of DNA synthesis in gamma-irradiated 3- and 7-day embryos of the silkworm which sharply differ in their radiosensitivity. It was shown that in 3-day embryos, the number of AP regions and DNA ruptures immediately after irradiation is significantly higher than in 7-day embryos. DNA synthesis is more radiosensitive in 3-day embryos as compared to that in 7-day ones.

[Effect of chronic low-intensity gamma irradiation on embryogenesis in the silkworm (Bombyx mori L.)].

Gamma irradiation of a grain during embryogenesis at an intensity only 100 times exceeding that of the natural radioactive background reduces by 4-7 h the average time of embryogenesis for different species and hybrids of thesilworm embryo. The 10- and 40-time increase in the radiation intensity decreases the stimulatory effect and leads to the delay in the development.

[Effect of low-dose gamma-irradiation of silkworm eggs on the development of the mulberry silkworm (Bombyx mori L.)].

Chronic gamma-irradiation of an egg at a dose-rate 100, 1000 and 4000 times as high as that of the natural radiation background significantly accelerates the development of Bombyx mori L. The caterpillar development may also be stimulated by a single exposure of the egg to 2 Gy radiation. The acceleration of the caterpillar growth promotes the increase in the cocoon weight and the raw-silk mass.