水稻两性生殖细胞的N-甲基-N-亚硝基脲诱变方法

N-甲基-N-亚硝基脲(MNU)被用于水稻(Oryza sativa)受精卵的诱变。通过水稻辽盐6号成熟生殖器官的MNU体内同步处理及后代群体筛查, 确立了水稻两性生殖细胞的MNU诱变方法。与辽盐6号受精卵的MNU处理相比, 各组条件下两性生殖细胞的MNU处理明显使M₁群体生长发育的指标降低及M₁-M₂群体中突变性状的发生率升高。两性生殖细胞在含有1.5 mmol?L ^-1 MNU和10 mmol?L ^-1 PO₄ ^3-的缓冲液(pH4.8)中处理60分钟, 突变性状发生率是基于受精卵MNU处理的3倍。进一步筛查M₃群体, 获得了包含新型植株和籽粒突变体的纯合突变体系列。研究结果表明, 水稻两性生殖细胞的MNU诱变可显著提高广谱诱变效率。该技术的应用可为水稻的未知功能基因鉴定和育种所需的各种突变体规模化开发提供高效的技术支撑。

Method for N-methyl-N-nitrosourea Mutagenesis on Hermaphroditic Germ Cells of Rice

N-methyl-N-nitrosourea (MNU) has been used in mutagenesis of fertilized eggs of rice (Oryza sativa). In this study, the method for MNU mutagenesis on hermaphroditic germ cells of rice was established by in vivo synchronous MNU treatment of mature germ-organs in the rice cultivar Liaoyan 6 and the screening of the progeny populations. As compared with MNU treatment of fertilized eggs in Liaoyan 6, MNU treatment of hermaphroditic germ cells under each group of conditions significantly decreased the growth and development indexes of M₁ populations and increased the incidence of mutant characters in M₁-M₂ populations. When the hermaphroditic germ cells were treated for 60 min in MNU buffer (pH 4.8) containing 1.5 mmol?L ^-1 MNU and 10 mmol?L ^-1 phosphate, the incidence of mutant characters was about 3 times higher than that based on the MNU treatment of fertilized eggs. A series of homozygous mutants including novel plant and grain mutants were obtained by further screening M₃ populations. The method for MNU mutagenesis on mature hermaphroditic germ-cells of rice significantly improved the efficiency of broad-spectrum mutagenesis. Its application can provide efficient technical support for large-scale development of various mutants for identifying unknown functional genes and breeding rice.