Construction of Brassica napus recessive nuclear sterile near-isogenic line and single cross hybrid production technology

The invention discloses construction of Brassica napus recessive nuclear sterile near-isogenic line and a single cross hybrid production technology. A fertile plant of a recessive sterile homozygous two-type line serves as a donor, and a temporary maintainer line serves as a recurrent parent for repeated rotation cross to obtain a new homozygous two-type line having the same genetic background with the temporary maintainer line; the sterile plant of the new recessive nuclear sterile homozygous two-type line and the temporary maintainer line with the same genetic background are hybridized to produce a complete sterile line; and then the complete sterile line and a restoring line are hybridized to produce a single cross hybrid. In the invention, the genetic background of the homozygous two-type line and the temporary maintainer line are quickly homogenized so that a commercial F1 hybrid is converted into the single cross hybrid from the original three way cross hybrid and is applied to production.