Linkage between an isozyme marker and a restorer gene in radish cytoplasmic male sterility of rapeseed (Brassica napusL.)

✍ Scribed by R. Delourme; F. Eber

• Publisher: Springer
• Year: 1992
• Tongue: English
• Weight: 781 KB
• Volume: 85-85
• Category: Article
• ISSN: 0040-5752
• DOI: 10.1007/bf00222863

✦ Synopsis

Co-segregation studies of isozyme markers and male fertility restoration showed that a restorer gene from radish was introduced into rapeseed along with an isozyme marker (Pgi-2). The radish chromosome segment carrying these genes was introgressed into rapeseed through homoeologous recombination, substituting for some of the rapeseed alleles. By crossing heterozygous restored plants to male-sterile lines and to maintainers, tight linkage was found between the restorer gene and the marker. The recombination fraction was estimated at 0.25 ± 0.02%. Although few restored plants lacked the radish isozyme marker, it was still possible to distinguish male-fertile from male-sterile plants by their PGI-2 patterns. Furthermore, homozygous and heterozygous restored plants could be separated by specific PGI-2 phenotypes. Thus, the Pgi-2 marker is now currently used in restorer breeding programs.