Fig. 4

Physical positions of SbPSTOL1 genes in the context of the QTL regions detected by multi-trait QTL mapping (Fig. 3d). The root morphology traits assessed after 13 days in nutrient solution with low-P are root diameter (RD, mm) and surface area of fine roots between 1 and 2 mm in diameter (SA2, in cm²). Possible pleiotropy between Gy (grain yield), SA2 and RD QTL, when detected, were depicted by slashes in the QTL designations. Physical positions and gene models for the SbPSTOL1 genes (https://phytozome.jgi.doe.gov/, v1.4 of the sorghum genome), a Sb03g006765, b the SbPSTOL1 cluster including Sb03g031690 and (c) Sb07g002840 are shown