Genetic architecture of biofortification traits in soybean (Glycine max L. Merr.) revealed through association analysis and linkage mapping

Abstract

Seed mineral elements are essential not only for seed germination and seedling morphological formation but also for human health. The genetic dissection of seed mineral accumulation is important for mineral biofortification in soybean. However, the molecular mechanisms controlling mineral element accumulation are genetically complex because a number of genetic loci are involved in the metabolic pathways of mineral accumulation in seeds. The objective of this study was to detect the genetic loci for mineral concentrations in soybean seeds, including calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn) and phosphorus (P). Quantitative trait loci (QTL) mapping for the corresponding traits was performed in 184 recombinant inbred lines (RILs) and 219 cultivated soybean accessions. The data for each year and the average across 2 years were used for identification and mapping of QTL controlling seed mineral concentrations. Linkage mapping in the RILs identified totally 35 significant QTL for the five seed mineral concentrations in three cases, some of which were colocalized. Association mapping in the 219 accessions detected 28 single-nucleotide polymorphisms associated with the seed mineral concentrations. Among these, BARC-018099-02516, which was associated with seed Zn concentration, was located close to qZn-11-2. There were 20 putative mineral-related genes in interesting regions of mineral QTL. Three QTL for seed weight were mapped in the RILs, two QTL for seed weight were co-localized with seed Ca, Zn and P concentration QTL which anchored to the same region on chromosome 11. These results will provide a profound understanding of the genetic basis for seed mineral accumulation in soybean seeds and the foundation for mineral biofortification through marker-assisted selection breeding.

Identification of Loci Controlling Mineral Element Concentration in Soybean Seeds

“…Such relatively high broad-sense heritability suggested that the phenotype was largely determined by the genotypic effect [20]. Similar heritabilities for these traits have been reported in previous studies (H 2 = 0.48 to 0.93) [14,16]. In addition, a signi cant and positive correlation between the concentrations of K and P was observed (0.65, Table S1).…”

“…More importantly, seven of these eight QTLs proved extremely robust as they could be successfully con rmed as impacting mineral element content in three additional trials. In previous GWAS studies, Ziegler et al [4] and Ning et al [14] reported 22 and 9 QTLs, respectively. Using a linkage mapping approach, Ramamurthy et al [2] reported 7 and Bellaloui et al [19] reported 11 QTLs associated with soybean seed Ca, K, P and S content.…”

“…A limited number of studies have aimed to determine the genetic architecture governing the accumulation of mineral elements in seeds and concluded these traits to be most likely controlled by many genes [2,14]. Zhang et al [15] Germplasm Collection to identify 9 QTLs (on chromosomes 1, 2, 5, 9, 10 and 13) associated with Ca, K, P and S content in soybean seeds.…”

Physiological and transcriptional responses to salt stress in salt‐tolerant and salt‐sensitive soybean (Glycine max [L.] Merr.) seedlings

“…Root dry mass was termed root biomass , whereas the stem and leaf dry mass were termed shoot biomass . The ion concentration measurement followed the procedure of our previous work (Ning et al, ). Briefly, soybean leaves and roots were ground in an IKA mill (A11 basic, IKA) to a powder with uniform particle size.…”

GENETIC SOURCES REQUIRED FOR SOYBEAN BREEDING IN THE CONTEXT OF NEW BIOTECHNOLOGies (review)

“…Molecular study revealed 35 QTLs associated with accumulation of Ca, Mg, Fe, Zn and P in soybean seeds. It creates the prerequisites for biofortification by MAS [57]. In addition, the researchers explore possibilities to improve utilization of these elements from soil by plants.…”