Identification of quantitative trait loci underlying soybean ( Glycine max ) 100‐seed weight under different levels of phosphorus fertilizer application

The “100‐seed weight (100‐SW)” trait is an important component of soybean quality and yield. Phosphorus (P) deficiency induces a wide array of metabolic effects that limits plant growth, especially in soybean. In this study, the 100‐SW values of a recombinant inbred line (RIL) population constructed by a cross between “Zhongdou27” and “Jiunong20” were evaluated in three tested environments under regular P and low P level conditions. We detected 12 additive quantitative trait loci (QTL) on nine linkage groups, explaining 8.11%–17.21% of the total phenotype variations. Two of these identified QTLs, qSW2‐3 and qSW17‐2, were identified in multi‐environments both under regular and low P level conditions, and explained 10.10%–14.11% and 10.12%–12.06% of the observed variations, respectively. One QTL, qSW17‐2, was novel which has been reported for the first time. Additionally, three QTLs (qSW10‐1, qSW13‐1 and qSW17‐1) were detected under low P conditions and the other QTLs were detected specifically under regular P levels. These particular QTLs improve our understanding of the genetic basis of P efficiency in soybean.