Fine-mapping of QTLs for individual and total isoflavone content in soybean (Glycine max L.) using a high-density genetic map
Fifteen stable QTLs were identified using a high-density soybean genetic map across multiple environments. One major QTL, qIF5-1, contributing to total isoflavone content explained phenotypic variance 49.38, 43.27, 46.59, 45.15 and 52.50%, respectively.
Soybeans (Glycine max L.) are a major source of dietary isoflavones. To identify novel quantitative trait loci (QTL) underlying isoflavone content, and to improve the accuracy of marker-assisted breeding in soybean, a valuable mapping population comprised of 196 F7:8–10 recombinant inbred lines (RILs, Huachun 2 × Wayao) was utilized to evaluate individual and total isoflavone content in plants grown in four different environments in Guangdong. A high-density genetic linkage map containing 3469 recombination bin markers based on 0.2 × restriction site-associated DNA tag sequencing (RAD-seq) technology was used to finely map QTLs for both individual and total isoflavone contents. Correlation analyses showed that total isoflavone content, and that of five individual isoflavone, was significantly correlated across the four environments. Based on the high-density genetic linkage map, a total of 15 stable quantitative trait loci (QTLs) associated with isoflavone content across multiple environments were mapped onto chromosomes 02, 05, 07, 09, 10, 11, 13, 16, 17, and 19. Further, one of them, qIF5-1, localized to chromosomes 05 (38,434,171–39,045,620 bp) contributed to almost all isoflavone components across all environments, and explained 6.37–59.95% of the phenotypic variance, especially explained 49.38, 43.27, 46.59, 45.15 and 52.50% for total isoflavone. The results obtained in the present study will pave the way for a better understanding of the genetics of isoflavone accumulation and reveals the scope available for improvement of isoflavone content through marker-assisted selection.
Composite interval mapping method
Quantitative trait loci
Recombinant inbred line
Restriction site-associated DNA sequencing
Specific length amplified fragment sequencing
Single nucleotide polymorphism
We wish to thank Professor Junming Sun (Chinese Academy of Agricultural Sciences, People’s Republic of China) for kindly supplying the 12 standards of isoflavone components. This work was supported by the National Natural Sciences Foundation of China (31401398); the China Agricultural Research System (CARS-04-PS09); the Project of Molecular Design Breeding for Major Economic Crops (2016yfd0101901) and the Research Project of the State Key Laboratory of Agricultural and Biological Resources Protection and Utilization in Subtropics.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Graham TL, Graham MY, Subramanian S et al (2007) RNAi silencing of genes for elicitation or biosynthesis of 5-deoxyisoflavonoids suppresses race-specific resistance and hypersensitive cell death in Phytophthora sojae infected tissues. Plant Physiol 144(2):728–740CrossRefPubMedPubMedCentralGoogle Scholar
- McCouch S, Cho Y, Yano M et al (1997) Report on QTL nomenclature. Rice Genet Newsl 14:11–12Google Scholar
- Smallwood CJ (2012) Detection of quantitative trait loci for marker-assisted selection of soybean isoflavone genistein. Dissertation, University of TennesseeGoogle Scholar