Identification of QTLs associated with multiple agronomic traits in Sorghum

Specific-locus amplified fragments (SLAF) is widely used to identify QTLs in crops. In our study, 11 agronomic traits were evaluated including plant height (PH), number of stem nodes (NSN), stem diameter (SD), panicle neck length (PNL), panicle length (PL), fresh stem weight (FSW), stem juice weight (SJW), Brix, panicle weight (PW), 100-grain weight (HGW) and number of days to heading (HD). After genome-wide SLAF marker analysis, 12 QTLs of 7 traits were obtained and located on five chromosomes. QTLs of plant height (qPH1, qPH2, qPH3) were detected on Chr 6 and Chr 9, with the phenotypic variations explaining (PVE) 27.13–29.02%. Two QTLs of fresh stem weight (qFSW1, qFSW2) were also detected on Chr 6 and Chr 9, which explained 27.10% and 16.08% of the phenotype variations, respectively. Besides, QTLs of Brix (qBRIX1, qBRIX2) were located on Chr 7 (PVE 11.70%) and Chr 9 (PVE 7.23%). qHD1 and qHD2 were mapped on Chr 1(PVP 31.56%) and Chr 6 (PVP 17.65%). Moreover, QTLs of both number of stem nodes (qNSN) and stem juice weight (qSJW) were detected on Chr 6, with PVE value 17.63% and 37.68%, respectively. The QTL controlling panicle neck length (qPNL) was located on Chr 3 and it explained 14.25% of the phenotype variation. Overall, the QTLs identified in this study can be to increase our understanding of the inheritance of the agronomic traits and gene cloning in sorghum.