Soybean seed sugars are among the most abundant beneficial compounds for human and animal
consumption in soybean seeds. Higher seed sugars such as sucrose are desirable as it contributes
to taste and flavor in soy-based food. Therefore, the objectives of this study were to use ‘Forrest’
by ‘Williams 82’ (F×W82) recombinant inbred line (RIL) soybean population (n=309) to identify
quantitative trait loci (QTL) and candidate genes that control seed sugar (sucrose, stachyose, and
raffinose) contents in two environments (North Carolina and Illinois) over two years (2018 and
2020). A total of 26 QTL that control seed sugars contents were identified and mapped on 16
soybean chromosomes (chrs.). Interestingly, five QTL regions were identified in both locations,
Illinois and North Carolina, in this study on chrs. 2, 5, 13, 17, and 20. Amongst 57 candidate genes
identified in this study, 16 were located within 10 Megabase (MB) of the identified QTL. Amongst
them a cluster of four genes involved in the sugars’ pathway was collocated within 6 MB with two
QTL that were detected in this study on chr. 17. Further functional validation of the identified
genes could be beneficial in breeding programs to produce soybean lines with high beneficial
sucrose and low raffinose family oligosaccharides.