大豆(甘氨酸max(L.)合并。)是一种营养丰富的作物,可以同时提供油脂和蛋白质。为了获得较好的大豆种质资源,提出了多种诱变方法。在不同类型的物理诱变剂中,碳离子束被认为是高效的高线性能量转移(LET),和伽马射线也被广泛用于突变育种。然而,尚未在大豆中阐明这两种诱变剂在发育过程中以及对表型和基因组突变的诱变作用的系统知识。为此,用碳离子束和伽马射线照射威廉姆斯82大豆的干燥种子。M1代的生物学效应包括存活率的变化,产量和生育率。与伽马射线相比,碳离子束的相对生物有效性(RBE)在2.5至3.0之间。此外,当使用碳离子束时,大豆的最佳剂量被确定为101Gy至115Gy,当使用伽马射线时,它是263Gy到343Gy。使用碳离子束从2000个M2家族中检测到总共325个筛选的突变体家族,使用伽马射线发现了336个筛选的突变家族。关于筛选的表型M2突变,使用碳离子束时,低频表型突变的比例为23.4%,使用伽马射线时,这一比例为9.8%。使用碳离子束很容易获得低频表型突变。在从M2代筛选突变后,它们的稳定性得到了验证,系统分析了M3的基因组突变谱。各种各样的突变,包括单碱基取代(SBS),插入-缺失突变(INDELs),使用碳离子束辐照和伽马射线辐照均检测到多核苷酸变体(MNV)和结构变体(SV)。总的来说,1988年使用碳离子束检测到纯合突变和9695纯合+杂合基因型突变。此外,当使用伽马射线时,检测到5279个纯合突变和14,243个纯合+杂合基因型突变。碳离子束,导致低水平的背景突变,有可能缓解大豆诱变育种中连锁拖累带来的问题。关于基因组突变,当使用碳离子束时,纯合基因型SVs的比例为0.45%,纯合+杂合基因型SVs为6.27%;同时,使用伽马射线时,比例分别为0.04%和4.04%。当使用碳离子束时,检测到较高比例的SV。在碳离子束照射下,错义突变的基因效应更大,在伽马射线照射下,无义突变的基因效应更大,这意味着碳离子束和伽马射线之间氨基酸序列的变化是不同的。一起来看,我们的结果表明,碳离子束和γ射线都是大豆快速诱变育种的有效技术。如果想获得具有低频率表型的突变,低水平的背景基因组突变和突变与较高比例的SV,碳离子束是最好的选择。
Soybean (Glycine max (L.) Merr.) is a nutritious crop that can provide both oil and protein. A variety of mutagenesis methods have been proposed to obtain better soybean germplasm resources. Among the different types of physical mutagens, carbon-ion beams are considered to be highly efficient with high linear energy transfer (LET), and gamma rays have also been widely used for mutation breeding. However, systematic knowledge of the mutagenic effects of these two mutagens during development and on phenotypic and genomic mutations has not yet been elucidated in soybean. To this end, dry seeds of Williams 82 soybean were irradiated with a carbon-ion beam and gamma rays. The biological effects of the M1 generation included changes in survival rate, yield and fertility. Compared with gamma rays, the relative biological effectiveness (RBE) of the carbon-ion beams was between 2.5 and 3.0. Furthermore, the optimal dose for soybean was determined to be 101 Gy to 115 Gy when using the carbon-ion beam, and it was 263 Gy to 343 Gy when using gamma rays. A total of 325 screened mutant families were detected from out of 2000 M2 families using the carbon-ion beam, and 336 screened mutant families were found using gamma rays. Regarding the screened phenotypic M2 mutations, the proportion of low-frequency phenotypic mutations was 23.4% when using a carbon ion beam, and the proportion was 9.8% when using gamma rays. Low-frequency phenotypic mutations were easily obtained with the carbon-ion beam. After screening the mutations from the M2 generation, their stability was verified, and the genome mutation spectrum of M3 was systemically profiled. A variety of mutations, including single-base substitutions (SBSs), insertion-deletion mutations (INDELs), multinucleotide variants (MNVs) and structural variants (SVs) were detected with both carbon-ion beam irradiation and gamma-ray irradiation. Overall, 1988 homozygous mutations and 9695 homozygous + heterozygous genotype mutations were detected when using the carbon-ion beam. Additionally, 5279 homozygous mutations and 14,243 homozygous + heterozygous genotype mutations were detected when using gamma rays. The carbon-ion beam, which resulted in low levels of background mutations, has the potential to alleviate the problems caused by linkage drag in soybean mutation breeding. Regarding the genomic mutations, when using the carbon-ion beam, the proportion of homozygous-genotype SVs was 0.45%, and that of homozygous + heterozygous-genotype SVs was 6.27%; meanwhile, the proportions were 0.04% and 4.04% when using gamma rays. A higher proportion of SVs were detected when using the carbon ion beam. The gene effects of missense mutations were greater under carbon-ion beam irradiation, and the gene effects of nonsense mutations were greater under gamma-ray irradiation, which meant that the changes in the amino acid sequences were different between the carbon-ion beam and gamma rays. Taken together, our results demonstrate that both carbon-ion beam and gamma rays are effective techniques for rapid mutation breeding in soybean. If one would like to obtain mutations with a low-frequency phenotype, low levels of background genomic mutations and mutations with a higher proportion of SVs, carbon-ion beams are the best choice.