小麦T型恢复系2114易位染色体在配子中的传递

Transmission of Translocation Chromosome of Wheat Restoring Line 2114 with Triticum Timopheevii Cytoplasm in Gametes

小伞山羊草携Ｔ型恢复基因的６Ｕ染色体片段经自然易位到小麦６ＡＳ上，育成了单基因Ｔ型恢复系“２１１４”。携有外缘染色体片段的易位杂合体产生的两种类型配子间存在竞争作用，从而引起易位染色体在配子中传递频率异常。“矮苏３Ａ”／２１１４的Ｆ１自交结实率为９１．６％±２．６％。Ｆ２群体中株高和育性的分离情况表明，Ｒｈｔ３基因在Ｆ２中按单基因分离模式正常分离，而携恢复基因的易位染色体没有按单基因的模式进行分离。以“苏麦３号Ａ”／２１１４的Ｆ１作父本与苏麦３号Ａ测交，根据ＴＣＦ１群体中可育株和不育株的比例，计算出易位染色体在雄配子中的传递率为３０．８％；以苏麦３号Ａ／２１１４的Ｆ１作母本，与不具恢复力的品种“苏麦３号”、“扬麦５号”作父本进行测交，其ＴＣＦ１群体中可育株和不育株分离比例表明，易位染色体在雌配子中传递正常。同时分析了引起易位染色体在雄配子中传递率低的原因，并提出了利用这条易位染色体的途径，使之在Ｔ型恢复系选育中发挥作用。

?114” was a monogenic fertility restoring line with Triticum timopheevii cytoplasm. It contained a fragment of chromosome 6U which was translocated naturally from Aegilops umbellulata. Competition between two types of gametes generated by heterotic translocation plants caused abnormal transmission of translocation chromosome in the gametes. Average selfed seed set rate of plants in the F 1 of the cross D Sumai 3A/2114 was 91 6%±2 6%.D Sumai 3 was a near isogenic line of Sumai 3 with dwarfing gene Rht3. The fertility of its male sterile line was easy to be restored.Segregation ratios of plant height and fertility in the F 2 plants of the cross showed that segregation of Rht3 gene was in accordance with the monogenic segregation model while the segregation ratio between fertile plants and sterile plants deviated from the expected ratio seriously. According to the ratio between fertile plants and sterile plants in F 1 group of the cross which (Sumai 3 A/2114)F 1 was used as male parent to make test cross with Sumai 3A,the transmission frequency of the translocation chromosome in the male gametes was 30 8%.Ratios between fertile plants and sterile plants in the F 1s of two crosses which (Sumai 3A/2114)F 1 were used as female parents crossed with Sumai 3 and Yangmai 5 respectively showed that the translocation chromosome transmitted normally through the female gamates. Discussion on the cause of low transmission frequency of the translocation chromosome in the male gametes and method for using the translocation chromosome was also made in the paper.That would be beneficial to the application of the translocation chromosome in the breeding of fertility restoring lines with Triticum timopheevii cytoplasm.