Seed germination and emergence of sunflower are seriously affected by water stress. In this study, SSR, SRAP, and AFLP markers were applied to construct a genetic linkage map by using the F6population derived from a cross of K55 (drought sensitive)´ K58 (drought resistant). For mapping quantitative trait loci (QTLs) for ninetraits of seed germination in sunflower, the parents and 187 F6family lines were used to investigate seed germination traits under normal condition (CK) and 18% polyethylene glycol (PEG-6000) (drought stress). A genetic map consisting of 17 linkage groups was constructed with 1105 loci (368 SSR, 368 SRAP, 369 AFLP) which covers 3846.0 cM and the length of each linkage group varies from 147.6 to 295.5 cM, the number of markers in each linkage group varies from 10 to 165 with an average distance of 3.48 cM. As a result, a total of 33 QTLs were detected. We identified fourteen additive QTLs for germination index (GI), germination rate (GR), embryo length (EL), radicle length (RL), embryo fresh weight (EFW), radicle fresh weight (RFW) under18% PEG con-dition with explained phenotypic variance ranging from 6.1% to 14.0%. Nineteen additive QTLs were identified for germina-tion energy(GE), radicle length (RL), embryo fresh weight (EFW), radicle fresh weight (RFW), embryo dry weight (EDW), radicle dry weight (RDW) under normal condition with explained phenotypic variance ranging from 6.1% to 25.8%. Each of Qefw5-2,Qefw5-1,Qefw5-4,Qrfw10,Qrfw5, andQrl9 could explain phenotypic variance over 10%. Nine QTLs affecting trait differences between stress treatment and control were identified, which are considered to directly contribute to drought toler-ance. These QTLs identified could provide important reference to molecular breeding for drought-resistance during seed ger-mination in sunflower.%干旱胁迫对向日葵发芽出苗有重要影响。以K55×K58组合衍生的187个F6重组自交系为材料,利用SSR、SRAP、AFLP 标记构建向日葵高密度遗传连锁图谱,设置正常水分(CK)和模拟干旱(18%聚乙二醇 PEG-6000)两种水分条件,调查9个芽期数量性状, PCR扩增株系,构建一张包含17个连锁群、1105个标记(368个SSR、368个SRAP和369个AFLP)的高密度遗传连锁图谱。该图谱覆盖基因组长度3846.0 cM,平均图距3.48 cM,连锁群长度147.6~295.5 cM,每个连锁群标记数10~165个。两种条件下检测到33个QTL,其中干旱条件下检测到发芽指数、发芽率、胚芽长、胚根长、胚芽鲜重和胚根鲜重6个性状的14个QTL,可解释6.1%~14.0%的表型变异；正常水分(CK)条件下检测到发芽势、胚根长、胚芽鲜重、胚根鲜重、胚根干重和胚芽干重6个性状的19个QTL,可解释6.1%~25.8%的表型变异。两种水分条件下检测到Qefw5-1、Qefw5-2、Qefw5-4、Qrfw5、Qrfw10和Qrl9共6个QTL的遗传贡献率超过10%,此外,还检测到9个影响干旱胁迫与正常水分条件下性状差值的QTL,可能对抗旱性有直接贡献。这些QTL可为向日葵芽期抗旱分子设计育种研究提供重要参考。
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