Radiosensitivity of the moss Drepanocladus aduncus (Hedw.) Mnkm

Radiosensitivity was determined in isolated fragments of Drepanocladus aduncus gametophytes cultured in vitro, on the basis of the growth reaction to acute gamma Co-60 radiation and postirradiation survival of the plants. A high resistivity of D. aduncus to this radiation was noted. At 12°C a 100 per cent LD was 120 kR and at 22°C it was 160 kR. The nuclear index of radiosensitivity (ICV - interphase chromosome volume) for various gametophyte cells has a value from 1.54 to 9.00 μm3. Drepanocladus aduncus plants exhibit postradiation developmental anomalies. In natural conditions they are characterised by an enhanced beta and gamma radiation activity. The plants contain Sr-90, Cs-137, much calcium, beryllium and lithium.