关键词: 白菜类作物, DH群体, 叶片形态学性状, 数量性状位点（QTL）, 叶片形态指数

Abstract: The aim of this study was to map and analyze QTLs controlling leaf traits in Brassica campestris L.，so as to provide information for molecular marker assisted selection（MAS）of breeding．QTL analysis was conducted for leaf width，leaf length，and leaf index in 2 Brassica campestris L. DH populations．The results showed that 9 QTLs located on 6 linkage groups were detected，including 6 QTLs for leaf length，2 QTLs for leaf index，and 1 QTL for leaf width．These 9 QTLs explained 7.1%-28.1% morphological variations of the 2 populations．QTL analysis indicated that the QTLs controlling leaf length and leaf index were located on adjacent positions in the 2 DH populations．According to genome re-sequencing data of parents，more markers were mapped in the QTL region of leaf index on A03 in the Z16_SZQ F1 DH population．Further analysis showed that the QTL controlling leaf index trait was located on the BrID111431 locus．One candidate gene，e. g. BrXTH9，was found by analysis with annotated genes between A. Thaliana and Brassica campestris L. which was 54 Kb physical distance from BrID111431．The transcript me analysis of natural population showed that BrXTH9 was highly correlated with leaf index，indicating that BrXTH9 may involve in regulation of leaf index in Brassica campestris L.

Key words: Brassica campestris L., DH population, Leaf morphological traits, Quantitative trait loci（QTL）, Leaf index