Omics advances and integrative approaches for the simultaneous improvement of seed oil and protein content in soybean (Glycine max L.)

Genetic improvement of soybean, one of the major crops providing edible oil and protein-rich food, is important to ensure balanced nutrition for the growing world population. To make soybean cultivation more rewarding, an increase in seed oil and protein content is most desirable. Here, a critical review of the efforts employed over a half-century to accomplish the improvement of soybean oil and protein content has been presented. Many studies have used diverse parental lines to map and characterize quantitative trait loci (QTL)/genes regulating these two essential traits. Here, we highlighted such genomic loci that were consistently identified with different mapping approaches, like QTL mapping, genome-wide association studies (GWAS), and meta-QTL analysis. In addition, the information generated through efforts utilizing omics approaches, such as genomics, transcriptomics, and proteomics has also been compiled to anticipate the molecular mechanism. Several innovative approaches like multi-parental mapping, induced mutagenesis, genomic selection, transgenics, and genome-editing have been discussed in terms of effective utilization of technological advances to improve the oil and protein content in soybean. Information provided here will be helpful for better understanding and designing an effective strategy for simultaneous improvement in seed oil and protein content in soybean.