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本文观察了岔根甜菜(Beta Patula Ait)、叶用甜菜(B.cicla)及普通甜菜(B.vulgaris)三种间杂种的F_1、F_2及F_3的减数分裂行为。各代减数分裂终变期,染色体联会成9个二价体。中期Ⅰ有棒状结合,也有环状结合。F_1、F_2、F_3各代中期出现单价体频率分别为0.23、0.18、1.13。后期Ⅰ出现染色体桥、落后等异常现象,各代频率分别为0.93、2.2和3.26。后期Ⅱ各代异常频率为0.41、0.75和0.32。异常四分体频率各代分别为0.16、0.13和0.66。异常频率有随世代增长而增加的趋势。结果表明,B.patula、B.cicla及B.vulgaris三个种的染色体组基本上是同源的。本文还讨论了杂种减数分裂稳定性及遗传育种上利用的可能性。
In this paper, we observed the meiosis behavior of F_1, F_2 and F_3 among three hybrids, Beta Patula Ait, B. cicla and B. vulgaris. All generations of the final stage of meiosis, chromosome association will be nine bivalents. Interim Ⅰ with rod-shaped combination, but also ring-shaped combination. F_1, F_2, F_3 appeared in the middle of each generation monovalent frequency were 0.23,0.18,1.13. Late stage I appeared chromosome bridge, backward and other anomalies, the generations of frequencies were 0.93,2.2 and 3.26. The anomalous frequencies of late stage II were 0.41, 0.75 and 0.32. The abnormal tetrad frequencies were 0.16, 0.13 and 0.66 for each generation. The frequency of anomalies tends to increase with age. The results showed that the genomes of B.patula, B.cicla and B.vulgaris were basically homologous. This article also discusses the stability of hybrid meiosis and the possibility of utilization in genetic breeding.