Crossablility of B.napus was studied through interspecific hybridization between B.juncea thermosensitive genie male sterile line K121S and several B.napus varieties by obverse and reverse cross method in order to transfer the TGMS to B.napus. Results showed that, there was the higher crossability in K121S with 8.93 seeds per flower under the method of B.juncea x B.napus, a-mong five B.napus parents H8 showed the best crossability with average 10.71 seeds per flower; under the method of B.napus x B.juncea, ...