ABSTRACT The commercial potato Solanum tuberosum L. 2n = 4x = 48 is a tetrasomic (AAAA) species, with a narrow genetic base. Wild genomic allotetraploid species such as S. stoloniferum (AABB) have great importance in potato breeding, but getting homoploid hybrid by direct crossing between the cultivated potato and wild allotetraploid species is difficult due to genic imbalance in endosperm. In this study chromosome pairing during metaphase I of meiosis in three exceptional homoploid hybrids between S. stoloniferum × S. tuberosum was analysed. The main chromosome configuration at metaphase I was bivalent and univalent with the frequencies of 15.17 and 6.56, respectively. Low frequency of trivalent (1.88) and tetravalent (0.7) was also observed. Further unequal segregation in first and second meiotic division was observed. Results indicated that although one genome of stoloniferum was different from its other genome as well as those of tuberosum, intergenomic pairing occurred between A and B genomes.

中文翻译：

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自身异源四倍体 (AAAB) 种间杂交马铃薯中的染色体配对

摘要 商业马铃薯 Solanum tuberosum L. 2n = 4x = 48 是四体 (AAAA) 种，遗传基础窄。野生异源四倍体物种如 S. stoloniferum (AABB) 在马铃薯育种中具有重要意义，但由于胚乳的基因失衡，很难通过栽培马铃薯与野生异源四倍体物种之间的直接杂交获得同倍体杂种。在这项研究中，分析了 S. stoloniferum × S. tuberosum 之间三个特殊的同倍体杂种中减数分裂中期 I 期间的染色体配对。中期 I 的主要染色体构型为二价和单价，频率分别为 15.17 和 6.56。还观察到低频率的三价 (1.88) 和四价 (0.7)。在第一次和第二次减数分裂中观察到进一步的不平等分离。