论文部分内容阅读
极低温下用~(30)CO—γ射线照射冬小麦风干种子,在确认极低温能减轻M_1代生理损伤的基础上,对M_2代的突变频率进行了研究。实验结果表明:极低温同常温比较,在20—30千伦照射量范围内,大部分性状的突变率有所降低。若分别以其LD_(50)(半致死剂量)为基准进行比较,即在辐射损伤相同的情况下,极低温却导致突变率的显著提高。由此推断,在极低温下照射能够有效地保存射线直接作用对遗传物质所诱发的变异。
The seedling of winter wheat was irradiated with ~ (30) CO-γ rays at very low temperature, and the frequency of M_2 generation mutation was studied on the basis of confirming that the hypothermia can reduce the physiological injury of M_1 generation. The experimental results show that the mutation rate of most of the traits is reduced in the range of 20-30 Kilon at very low temperature compared with normal temperature. If LD_ (50) (semi-lethal dose) were used as a benchmark for comparison, that is, under the same radiation damage, extremely low temperature led to a significant increase in mutation rate. It can be inferred that irradiation at extremely low temperatures can effectively preserve the direct genetic variation induced by the radiation.