Purity identification for cytoplasm male sterility three-line hybrid seeds is very important in oilseed rape seed production. One hundred and seventy-three pairs of SSR primers were screened for polymorphic amplification between the parental lines of Zhongyouza No.8. Among those primers, six pairs amplified clear bands specific to either of the parents, with no difference among individual plants within lines. Three pairs of the primers, P051, P078 and P203, amplified all specific bands of both parents in F1 hybrid plants. Using the three primers, 32 DNA samples from Zhongyouza No.8 single plants were analyzed. P078 and P203 displayed the same result on seed purity. P078 was used to analyze a Zhongyouza No.8 seed sample whose purity had been identified in field. The result showed that the seed purity identified by SSR markers was very similar to field observation, indicating SSR primer pairs P078 and P203 can be used for quick and accurate identification of seed purity of Zhongyouza No.8.
