TABLE 1

Characteristics of four genetic linkage maps and their consensus map constructed using DH lines of B. napus, genotyped with RFLP and SSR markers

HUAMFRVSYNConsensus
No. of DH lines 162 170 164 162NA
No. of RFLP probes 132 127 124 140 167
No. of RFLP loci detected 243 218 205 312 508
 EcoRI  89  96  90 119NA
 HindIII 154 122 115 193NA
No. of RFLP loci/probe   1.84   1.70   1.65   2.23   3.02
No. of RFLP loci with a null allele  12  16  12  12  37
No. of SSR loci   0   0   0   2   2
No. of unlinked loci   5   0   0   3NA
No. of linkage groups  19  19  19  19  19
Average linkage group length (cM)  77  74  77  88 100
Total map length (cM)14601398145316681823
Average distance between loci (cM)   7.3   7.6   7.5   6.0   3.8
No. of loci with segregation distortion
 0.01 < P < 0.05  19  15  12  43NA
 0.001 < P < 0.01  13  23  21  44NA
 P < 0.001  49  39  48  83NA
  • NA, not applicable.