甘蓝型油菜显性核不育基因及与恢复基因的等位性分析

 【目的】弄清2个不同来源的甘蓝型油菜显性核不育系609AB和Rs1046AB显性核不育的遗传模式及其不育基因的等位性。【方法】采用临保系测验法和不育系可育株与临保系的杂交回交，分析恢复基因与不育基因和2个不育基因的等位关系。【结果】筛选得到28个甘蓝型油菜恢复系，确认其中15个恢复系恢复基因与609A不育基因等位，进一步证实了甘蓝型油显性核不育的复等位基因遗传，原来视为2对显性基因遗传的纯合型不育系Rs1046AB，其可育株携带的恢复基因与不育基因等位，Rs1046B的恢复基因与609A的不育基因等位。【结论】Rs1046AB和609AB均符合复等位基因遗传模式，2个不育基因等位，不育系不育株的基因型为MsMs，可育株的基因型是MsMf。

Allelism Analysis of Dominant Genic Male Sterility Gene and Its Restorer Gene in Brassica napus

【Objective】 Dominant genic male sterility (DGMS) in Brassica napus is gaining importance in breeding program and utilization of heterosis. The multiple allele inheritance model has been characterized recently by analyzing the allelism between the male sterility allele (Ms) in 609A and the fertility restoration allele (Mf) in 609B as well as the alleles from several restorers tested. The present study was designated to provide further validation of the result with more restorers and another DGMS line. 【Method】Extensively screening was made through crossing 609A with parental materials, and the restored F1 s were subjected to allelism analysis with temporary maintainer test methodology. The fertile plants in Rs1046AB were crossed with temporary maintainers and the fertile plants in the subsequent progenies were selected to be selfed and backcrossed. The analysis of allelism between the two sterile lines was completed through testing the allelism between the Ms in 609A and the Mf in Rs1046B. 【Result】Twenty eight restorers for DGMS in 609A were screened out, out of which 15 were tested for allelism. All the alleles from the restorers tested were identified as being allelic to the Ms in 609A, because the testcross populations segregated in an expected 1﹕1 ratio for multiple allele inheritance model rather than the expected ratio of 3:1 for the digenic interacting model. Thus, the multiple allele inheritance model for DGMS was further confirmed. Meanwhile, crossing Rs1046B with maintainers produced F1s segregating in a ratio of 1﹕1, and there were only fertile plants in the selfed and backcrossed populations, which clearly indicated that Mf is allelic to Ms. Accordingly, Rs1046AB was demonstrated to inherit in the same way with 609AB. The restorer allele from Rs1046B restored 609A and the testcrosses made between the F1 and maintainers segregated in a ratio of 1﹕1, showing the restorer allele was allelic to Ms in 609A. 【Conclusion】Both of the sterile lines are conditioned by a locus with three alleles and the two Ms are allelic to each other. The genotypes of the sterile plants and fertile plants in the sterile line are MsMs and MsMf, respectively.