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本文研究了栽培大豆绥农4号等5个品种和1个品系分别与野生大豆、半野生大豆杂交,杂种F_1代花粉母细胞减数分裂的行为。以染色体组亲和指标,终变期二价体的交叉频率,鉴定杂交亲本的亲缘关系。 观察结果表明,杂交亲本和大部分杂种F_1代花粉母细胞减数分裂行为是正常的,减数分裂中期Ⅰ为20个二价体。11个亲本中期Ⅰ环状二价体占多数,少数为棒状二价体。有少数花粉母细胞出现二价体联会消失现象,中期Ⅰ没有单价体,后期Ⅰ和减数分裂Ⅱ均正常,四分孢子中无微核出现。杂交亲本中期Ⅰ环状二价体和棒状二价体的数目有差异,说明不同亲本的亲和力不同。 13个杂交组合F_1代的减数分裂行为有差异,染色体配对不稳定,二价体表现过早分离。如杂交组合中期Ⅰ二价体数在18—20之间,联会消失二价体数目较少。二价体数在5—20个之间,联会消失的二价体数目最多为15个。后期Ⅰ出现少数落后染色体,四分孢子内有少数微核。
In this study, we studied the hybridization of F_1 pollen mother cells and meiosis of five F1 hybrid cultivars including Suinong 4 and 1 strain with wild soybean and semi-wild soybean respectively. Based on the crossover frequency of chromosome-specific affinity index and terminal divalent body, the genetic relationship of hybrid parents was identified. The observation results showed that the meiosis of F_1 pollen mother cells in hybrid parents and most hybrids was normal, and metaphase Ⅰ in meiosis was 20 bivalents. The 11 parents metaphase Ⅰ cyclic divalent accounted for the majority, a small number of rod-like bivalents. A small number of pollen mother cells appear disappeared divalent body association, metaphase Ⅰ no monovalent, late and meiosis Ⅱ were normal, no micronucleus appeared in tetrad spores. There were differences in the number of metaphase I cyclic and bivalent bars in the hybrid parents, indicating different affinities of different parents. There were differences in the meiosis behavior among F1 hybrids in the 13 cross combinations, the chromosome pairing was unstable, and the bivalent body showed premature segregation. For example, if the crossover I divalent body number of hybrids is between 18-20, the number of disappeared bivalent bodies will be less. The number of bivalents is between 5 and 20, and the number of divalent bodies disappeared by the association is up to 15. There are a few backward chromosomes in late stage Ⅰ, and a few in micronucleus in tetradospores.