Genetic Analysis and Gene Mapping for a Short-Petiole Mutant in Soybean (Glycine max (L.) Merr.)

Short petiole is a valuable trait for the improvement of plant canopy of ideotypes with high yield. Here, we identified a soybean mutant line derived short petiole (dsp) with extremely short petiole in the field, which is obviously different from most short-petiole lines identified previously. Genetic analysis on 941 F2 individuals and subsequent segregation analysis of 184 F2:3 and 172 F3:4 families revealed that the dsp mutant was controlled by two recessive genes, named as dsp1 and dsp2. Map-based cloning showed that these two recessive genes were located on two nonhomologous regions of chromosome 07 and chromosome 11, of which the dsp1 locus was mapped at a physical interval of 550.5-Kb on chromosome 07 near to centromere with flanking markers as BARCSOYSSR_07_0787 and BARCSOYSSR_07_0808; whereas, the dsp2 locus was mapped to a 263.3-Kb region on chromosome 11 with BARCSOYSSR_11_0037 and BARCSOYSSR_11_0043 as flanking markers. A total of 36 and 33 gene models were located within the physical genomic interval of dsp1 and dsp2 loci, respectively. In conclusion, the present study identified markers linked with genomic regions responsible for short-petiole phenotype of soybean, which can be effectively used to develop ideal soybean cultivars through marker-assisted breeding