Abstract:In order to study the genetic mechanism of rice lodging resistance-related traits,a set of doubled haploid (DH) lines derived from a cross between indica cultivar Zhaiyeqing 8 and a japonica variety Jingxi 17 were used to investigate the traits related to lodging resistance including root thickness (BRT), total root number (TRN), maximum root length (MRL), root dry weight (RDW), root shoot ratio (RSR), tiller number (TN), plant height (PH), plant perimeter (PP), single tiller diameter (STD) and shoot dry weight (SDW). Using a constructed molecular linkage map, the QTL analysis was carried out at full heading stage under hydroponic culture and a total of thirteen QTLs were detected. Among them, only one QTL each for BRT, RSR, PP and STD was detected on chromosomes 8, 1, 7 and 8 respectively, two QTLs each for TN (on chromosomes 1 and 2), MRL(on chromosomes 1 and 6) and RDW (on chromosomes 1 and 12), and three QTLs for PH on chromosomes 1, 4 and 8 were detected. The highly significant positive correlations were observed between every two root traits by correlation analysis, and the aboveground traits of TN, PH, PP, STD and SDW also exhibited significant or highly significant positive correlation with root traits except for RSR. In addition, the multiple regression analysis also showed that there were significant linear effects between root traits and other aboveground traits of PH, PP, STD and SDW. These results will facilitate theoretical studying for further understanding the genetics basis of rice lodging resistance factor and formulating lodging resistance breeding strategy.