Fig. S1 Histograms of frequency distribution of root traits for RIL population. TRL, RSA, VOL, TIP and MRL denote total root length, root surface area, root volume, number of root tips and main root length, respectively

Fig.S2 Comparison between root and PH QTLs detected on chromosome 4D in both DH (A and C) and RIL (B and D) populations. Likelihood of odds ratio (LOD) curves show plant height QTLs(A and B) and root QTLs (Cand D). Peak shows(D) the possible location of root QTL is far away from Rht2 locus. indicats the position of Rht2 locus.

Supplementary Table 1 Comparison of the QTL location between previous studies and this study

Chromosome / QTL / Marker / Related traits for which QTLs have been detected in previous studies
1B / QTip-1B(RIL) / Xbarc188 / TRL, MRL(Liuet al. 2013), RN (Li et al. 2007)
2A / QTrl-2.1A, QRsa-2A,QTip-2A.1 / Xbarc212 / PH (Liuet al. 2014; Cui et al. 2011), TRSA (Baiet al. 2013), TRL, RVOL, RSA, FRK(Ibrahim et al. 2012)
2B / QTrl-2B / Xwmc360 / SRN (Liuet al. 2013), PRL , TRL, PRL, MRL (Renet al. 2012), RDM (Li et al. 2007), RN, MRL (Zhou et al. 2005)
2B / QTrl-2B(RIL) / Xcfd238 / TRL,PRL,MRL (Renet al. 2012)
3A / QTrl-3A,QRsa-3A, QTip-3A.1 / Xbarc1060 / MRL(WS),Seminal root angle (Liuet al. 2013), RN (Renet al. 2012)
3B / QMrl-3B.2(RIL) / XBarc164 / TRL, RVOL (Baiet al. 2013)
4A / QTip-4A(RIL) / Xgwm610 / PRA, (Liuet al. 2013), RVOL, TIP(Ibrahim et al. 2012)
4D / QTrl-4D,QRsa-4D.2, QRvol-4D.3,QTip-4D.2,QMrl-4D.2 / Xbarc334 / This study
4D / QRsa-4D.1 QRvol-4D.2, QTip-4D.1,QMrl-4D.1 / Xbarc334 / This study
4D / QTrl-4D(RIL),QRsa-4D(RIL)
QTip-4D (RIL),QPh-4D.1 QPh-4D(RIL) / Rht2 / TRL, RSA, RVOL, RDW,PH (Baiet al. 2013)
5B / QRvol-5B.2(RIL) / Xbarc74 / RSA (Liuet al. 2013), TRL, RVOL (Baiet al. 2013), RL(Li et al.2007)
5B / QMrl-5B(RIL) / Xbarc216 / MRL(Liuet al. 2013)

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