Abstract: The field experiments were conducted by using 6 pairs of rapeseed combinations with resistance and corresponding non-resistant isogenic lines to investigate the differences in disease resistance, agronomic traits and yield when resistance loci CRa/CRb and PbBa8.1 were introgressed into different varieties (materials). The results showed that the incidence rate of all non-disease resistant materials in 6 pairs of rapeseed combinations was more than 97.8%, and the disease index was over 95.6. The incidence and disease index of the materials introgressed with the CRa/CRb resistance locus were higher, the incidence was 96.7%, 86.0% and 82.2%, respectively, and the disease index was 85.9, 67.7 and 36.0, respectively, but both were lower than those of the corresponding non-resistant isogenic materials; the materials introgressed with the PbBa8.1 resistance locus exhibited better resistance to clubroot, the incidence was 10.6%, 1.8% and 5.8%, respectively, and the disease index was 8.0, 1.5 and 4.7, respectively. The agronomic traits of rapeseed introgressed with the CRa/CRb resistance locus, such as plant height, effective branch location, effective number of pods per plant and number of kernels per pod, were lower than those of rapeseed introgressed with the PbBa8.1 resistance locus, which ultimately affected the yield.

Key words: rapeseed, clubroot, resistance locus, agronomic traits, disease resistance, yield