Mapping Of A Restorer Gene For The Rapeseed (Brassica Napus L.) Cytoplasmic Male Sterile Line 681A

Rapeseed (Brassica napus L.) demonstrates remarkable heterosis. Hybrid seed production with the help of cytoplasmic male sterility is one of the most important ways to utilization of heterosis in rapeseed. In recent years, basic researches on the mechanism of cytoplasmic male sterility and its fertility restoration have advanced greatly in such crops as maize and rice. A new rapeseed double-low CMS line 681A , its maintainer 68IB and its restorer 714 were developed by the Institute of Oil Crops, Hunan Agricultural University. Using CMS line 681A and its maintainer 68IB, its restorer line 714 and 681 AX714 FI, FI as the materials, we carried out the genetic studies of fertility restoration and molecular mapping of the restorer gene. The following conclusions could be drawn:1. Observation on male fertility of the CMS line 681 A, the restorer 714and681AX714 FI and ? populations showed that fertility restoration of the CMS line 681A is controlled by a single dominant gene.2. The CMS line 681 A, the restorer 714 and FI populations of 681 AX 714 consisting of 110 plants were used for molecular mapping of the restorer gene by bulk segregant analysis(BSA). 500 10-mer random primers were chosen for polymerase chain reaction (PCR) amplification. It is found that the polymorphism between the two bulks male fertile and male sterile could be detected by 16% of the primers, and the RAPD marker S1039s2o was tightly linked to the restorer gene of the restorer 714 with the crossover of 5.45% and genetic distance of 5.47cM.