Microspore embryogenesis and cytoplasmicmale sterility system (CMS) are two approacheswidely
exploited in Brassica napus
breeding for production of homozygous doubled haploid (DH) lines and F1 hybrids
respectively. Cytoplasmic male sterility system (CMS) is one of the most important pollination systems for
hybrid seed production and utilisation of doubled haploid system to quickly prepare fully homozygous fertility
restorer lines for CMS Ogu
-INRA is very beneficial. Generally, only a small part of microspore-derived embryos
is used for plant regeneration, without any knowledge about their properties. Therefore, the possibility of early
detection of desirable genotypes bearing a single dominant nuclear fertility restorer (Rfo
) gene, can double the
success of selection and reduce the production costs.
To maximize the efficiency and yield of regenerated microspore-derived embryos (MDEs) with the Rfo
gene, a protocol for reliable and early, non-destructive selection of desired MDE genotypes was developed. The
total amount of 636 cotyledonary embryos was tested by PCR, out of which 37% (237/636) were shown to
bear the Rfo
gene (instead of 50% according to the expected 1:1 segregation ratio for a single copy gene) and
218 of these fertility restorer plants were fully grown to flowering stage. New molecular marker has been
demonstrated to have 100% of co-segregation with the phenotypic evaluation.
Technique developed in this study provides early and non-destructive sampling of embryonic tissue
and the use of new markers for simple and efficient control of the presence of Rfo
gene in all accessions.