Breeding for a genetic male-sterile line of level-head ecotype in Chinese cabbage (Brassica campestris L. ssp. pekinensis).

A cylindrical ecotype AB line was applied as a male sterile source of multiple-allele inherited male sterility in Chinese cabbage.Recurrent backcrossing was employed to transfer traits,while the genotype was identified through test cross.The male sterile gene was successfully transferred into a level-head ecotype DH strain S50 of Chinese cabbage derived from microspore culture.A male sterile line,which belongs to level-head ecotype of Chinese cabbage with 100% male sterility and 100% male sterile plants and similar to S50 in botanical characters,was successfully developed.