Germplasm Enhancement in Soybean (Glycine max, L. Merr.) Through Genome Editing and Mutation
Soybean (Glycine max (L.) Merrill) belongs to legume family which has various uses as oil, protein, and animal feed. For the sustainable soybean production to meet the demand throughout the world, soybean research communities are working to improve the soybean germplasm. New soybean mutant populations were developed through induced EMS mutagenesis (60mM concentration), using newly released variety JTN-5203. From 15,000 treated seeds, we produced 1,820 M2 populations. Around 20,000 seeds were planted in the field to get M3 populations and DNA were extracted from 6,400 individual plants. DNA were quantified, standardized to 200ng/ul, and pooled to create a mutant library. Several mutants with altered plant architecture and seed morphology were identified. Using near infra-red (NIR), we have identified mutants with high oleic acid, total oil, sucrose, protein and low linoleic, and linolenic acid contents which can be used for further screening and developing into new germplasm. Then, we screened this EMS and a fast neutron (FN) mutagenized population for resistance to sulfonylurea herbicide. Total of 8,000 seeds in each mutagenized population were treated with SU and no resistant mutant were recovered from either of these populations. Apart from induced mutagenesis, targeted mutagenesis Clustered Regularly Interspaced Palindromic Repeats/ CRISPR associated (CRISPR/Cas9) system was also used for targeting genes involved in root hair and trichome developments including caprice (CPC) and triptychon (TRY). Three guide RNAs (gRNAs), specific to the target genes were designed and cloned into a binary vector Cas9PMDC123. One gRNA was successfully inserted into soybean using Agrobacterium mediated transformation. CRISPR/Cas9 in this event resulted in a successful targeted nucleotide change in CPC gene which ultimately led to substitution of glutamate with lysine (E60K). The obtained mutants displayed bushy and long hairy root phenotype. This research has resulted in a valuable genetic resource for soybean which can be screened for important agronomic traits both in forward and reverse genetic approach.
Molecular biology|Genetics|Plant sciences
C. M. Sabbir Ahmed,
"Germplasm Enhancement in Soybean (Glycine max, L. Merr.) Through Genome Editing and Mutation"
ETD Collection for Tennessee State University.