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本文研究了甜菜三体自交与回交后代中Ⅱ号染色体孢子形成与遗传规律。结果表明。甜菜Ⅱ号三体花粉母细胞减数分裂中期Ⅰ,三个同源染色体的结合方式以8Ⅱ+1Ⅳ类型为主,其三价体出现的频率为53.11%;后期Ⅰ染色体的分离9～10(T6.92%)模式和后期Ⅱ9—9—10—10(77.14%)模式最高,证明甜菜Ⅱ号三体三个同源染色体大部分以正常形式分离.在减数分裂过程中,观察到1.66%附加染色体的姊妹染色单体分离,及0.95%的染色单体错误分离的现象;甜菜Ⅱ号附加染色体主要通过雌配子传递,传递率为22.22%,而且Ⅱ号三体可以通过雌配子把其类型特征稳定地遗传给后代.
In this paper, the formation and genetic rule of chromosome number Ⅱ in selfing and backcrossing of sugar beet were studied. The results show. The meiosis of sugar beet Ⅱ tricolor body pollen mother cells metaphase Ⅰ, the binding mode of three homologous chromosomes is mainly 8Ⅱ + 1Ⅳ type, the frequency of trivalent body appearance is 53.11%; the segregation of late chromosome Ⅰ is 9-10 ( T6.92%) pattern and the late Ⅱ9-9-10-10 (77.14%) pattern, which showed that most of the three homologous chromosomes of trisomy 3 were separated in normal form. During meiosis, 1.66 S sister chromatid separation with additional chromosomes, and erroneous separation of 0.95% chromatids. The additional chromosomes of beet II were mainly transmitted by female gametes, with a transmissibility of 22.22%. Moreover, trisomy II could be transformed by female gametes Type characteristics are consistently inherited to offspring.