LAUSR

Plant height is one of the most important agronomic traits in soybean. The semi-dwarf soybean cultivars could improve lodging resistance and solar radiation use efficiency so as to increase soybean yield. However, the inheritance of semi-dwarf traits has not been intensively studied and few semi-dwarf genes have been isolated in soybean. In this study, we use specific-length amplified fragment sequencing (SLAF-seq) with bulked segregant analysis (BSA) to map the semi-dwarf gene in soybean. Plant height of 213 F 2:3 families, derived from a cross between ‘Jimidou-1’ (semi-dwarf) and ‘Gongjiao9112’ (tall), was evaluated under field conditions. Genetic analysis indicated that the semi-dwarf trait was controlled by one single recessive gene. Associated with the semi-dwarf trait, SLAF-seq combined with BSA was used to develop polymorphic SLAF markers and identify a 1.04 Mb genomic region, which was designated as sdf -1 . The sdf -1 locus was delimited to 80.72 kb region on chromosome 19 by KASP SNP markers developed from the SLAF markers and 6 K SNP chip. There were 14 putative genes in the associated region. From annotation information, three genes ( Glyma.19g194800 , Glyma.19g194500 and Glyma.19g195200 ) might be interesting candidate genes that are highly related to plant height growth or semi-dwarf trait. The successful identification and localization of sdf -1 could help reveal molecular mechanisms underlying soybean semi-dwarfism and to indirectly improve total yield.