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对Irisjaponica、I confusa和它们的人工种间杂种花粉母细胞减数分裂中期Ⅰ染色体配对行为、形态学和繁育特征进行了分析 ,结果表明 :(1)I japonica和I confusa的形态差异较小 ,杂种F1形态介于亲本之间 ;(2 )人工杂交比较容易 ,杂种种子能正常发育 ;杂种F1体细胞染色体数为 2n =30 ,减数分裂中期I染色体配对频率很高 ,为 13 9个二价体 ,构型为0 95Ⅰ + 5 95Ⅱ (棒形 ) + 7 95Ⅱ (环形 ) + 0 0 5Ⅲ + 0 2 7Ⅳ ,表明它们有相似的染色体组 ,亲缘关系很近 ;(3)杂种中有少量的三价体和四价体存在 ,可能是亲本染色体间发生了结构重排或是部分同源染色体配对 ;(4)杂种中大多数细胞存在 2个单价体 ,有的高达 8个单价体 ;花粉育性为 5 0 5 1% ,不能正常结实 ,表明I japonica和I confusa间存在生殖隔离 ,是独立的生物学物种 ;(5 )杂种F1减数分裂前期可观察到细胞融合 ,这可能是造成I japonica和I confusa不同居群出现多倍体和非整倍体的重要原因。
The pairing behavior, morphological and reproductive characteristics of metaphase Ⅰ in pollen mother cells of Iris japonica, I confusa and their interspecific hybrids were analyzed. The results showed that: (1) The morphological differences of I japonica and I confusa were small, F1 hybrids between the parents; (2) artificial hybridization easier, hybrid seeds can develop normally; hybrid F1 somatic chromosome number 2n = 30, metaphase I chromosome pairing frequency is high, 13 9 two (095Ⅰ +5 95Ⅱ (rod) +7 95Ⅱ (ring) +0.5Ⅲ + 0 2 7Ⅳ), indicating that they have similar genomes and are closely related to each other. (3) There are a few (4) Most of the hybrids have 2 monovalent and some 8 monovalent bodies; (3) The pollen fertility was 5 0 5 1% and could not be normal, which indicated that reproductive isolation existed between I japonica and I confusa and was an independent biological species. (5) Cell fusion could be observed in the pre-meiotic stage of hybrid F1, which may be Cause I japonica and I confu sa different populations appear polyploid and aneuploidy important reason.