刘忠祥1 徐大鹏2,3 姚泽恩2,3 寇思荣1 王晓娟1 杨彦忠1 连晓荣1 周玉乾1 何海军1 李志明1

:采用252Cf 裂变中子源辐照玉米自交系LY8405和PH6WC种子,探索中子辐照玉米种子的生物学效应,筛选适宜的中子辐照剂量,以获得基因定位、克隆及其功能分析的突变体材料。结果表明:低吸收剂量(0.46?4.19 Gy)的中子辐照玉米干种子后,对自交系LY8405的出苗率有一定的抑制作用,对自交系PH6WC的出苗率有一定的促进作用;两材料M1畸变率、变异率、遗传总变异率,随着辐照剂量的增加有逐步升高的趋势,其中辐照剂量为4.19 Gy时对LY8405最为有效,畸变率、变异率、遗传总变异率分别为27.8%、38.9%、66.7%;辐照剂量为2.48 Gy时对PH6WC最为有效,畸变率、变异率、遗传总变异率分别为7.1%、14.3%、21.4%;M2代株高、穗位、叶片数、雄穗分枝数、穗长、穗粗、穗行数、轴粗等主要农艺性状变异随辐照剂量的增加,其变异系数也随之增加。研究表明不同基因型玉米种子对快中子辐射剂量的敏感性不同,初步认为2.48-4.19 Gy的辐照剂量是玉米快中子辐照处理的适宜剂量。 英文摘要: Maize inbred lines LY8405 and PH6WC were irradiated using 252Cf fission neutron source in order to study the biological effects and rules of neutron irradiation on maize seeds, meanwhile screening suitable neutron irradiation dose and creating mutants for gene mapping,cloning and its functional analysis,. The results showed that the germination rate of LY8405 was descended after Neutron irradiation at low absorbed doses (0.46?4.19 Gy), however that of PH6WC was increased. With irradiation dose increasing, the rates of distortion, mutation and total genetic variation of the two materials M1 were all added. LY8405 showed the most sensitively biological effects at 4.19 Gy irradiation dose, the rates of distortion, mutation and total genetic variation were 27.8%, 38.9% and 66.7%, respectively; PH6WC showed the most sensitive effect at 2.48 Gy irradiation dose, the rates of distortion, mutation and total genetic variation were 7.1%, 14.3% and 21.4%, respectively. Besides, the coefficient of variation of the agronomic characters, including plant height, ear position, leaf number, tassel branch number, spike length, ear diameter, kernel rows per spike and axis width, were all raised with the rising of irradiation dose. The paper indicated that the sensitive degree of maize genotype is different to fast neutron radiation dose; initially considered that 2.48-4.19 Gy is suitable dose of irradiate maize seed using 252Cf fission neutron source.
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