Chapters authored
Genetic Control of Cadmium Concentration in Soybean Seeds
Cadmium (Cd) is a chemical element present in the soil. At high concentrations Cd can cause physiological and morphological damages to plants and it is highly toxic to human beings. Minimizing the intake of Cd and other heavy metals from food consumption is an important health issue. Efforts have been made to identify genetic elements that are involved in Cd detoxification in plants. Heavy metal transporter 3 (HMA3) plays a role in sequestration of Cd into vacuoles in soybean (Glycine max). Inheritance studies revealed that low Cd accumulation in soybean seed is controlled by a major gene (Cda1) with the allele for low accumulation being dominant. Major QTL for seed Cd accumulation, Cda1 and cd1, have been identified independently for low Cd accumulation and both mapped to the same location as on LG-K (Chromosome 9) with simple sequence repeat (SSR) markers. A single nucleotide substitution causing a loss of function of the ATPase was found. The SSR markers linked to the Cda1 and Cd1gene(s)/or QTLs and the SNP marker in the P1B-ATPase metal ion transporter gene in soybean can be utilized in marker assisted selection (MAS) for developing food grade soybean varieties.
Part of the book: Grain Legumes
Food Grade Soybean Breeding, Current Status and Future Directions
Soybeans possess average 20% oil and 40% protein content and are a major source of protein and fatty acids in human and animal nutrition. Soybean cultivars are classified as commodity type, which are used for edible or industrial oil and animal feed, and food-type, which are used for human consumption in fermented foods and non-fermented foods. Major breeding targets for food grade soybeans are high protein and sucrose content. Developing cultivars with desired seed size and appearance depends on the type of soyfood for which the soybeans are destined. Seed with high protein content (>45%), low oil content, high sucrose, and low oligosaccharide content are suitable for making soymilk and tofu. For soyfood such as natto, soybean seed with a high content of carbohydrates are preferred. Since, molecular markers linked to the target food traits have been developed, transfer of the food grade traits among soybean varieties is possible through marker-assisted selection (MAS) to track the target gene/QTLs. Introgression of wild soybean alleles through genomics assisted breeding (e.g., GWAS, haplotype blocks, NIL, etc.), high-throughput phenotyping, mutagenesis and genome engineering/editing would improve protein without yield drag, pleiotropic effects, and background/allelic effects in breeding food grade soybean.
Part of the book: Legume Crops