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对无融合生殖悬铃叶苎麻(2n=42)和有性生殖悬铃叶苎麻(2n=28)花粉母细胞(PMC)减数分裂行为进行比较研究,从而推断两者之间的进化关系;探索无融合生殖悬铃叶苎麻(B.tricuspis)发生的细胞遗传学基础,为无融合生殖发生的遗传学研究提供理论依据。在无融合生殖类型经诱导所产生的PMC的减数分裂过程中,发现有丰富的三价体形成,属典型的同源三倍体减数分裂行为特征;而有性生殖类型PMC的减数分裂行为绝大多数正常,但也存在少量异常现象。其中有些异常行为,可能与未减数配子(2n)的形成紧密相关。因而推断,在有性生殖类型的生殖过程中,可能发生了未减数配子(2n)与减数配子(n)的融合,产生了同源三倍体合子,这应该是无融合生殖悬铃叶苎麻发生的重要的细胞遗传学基础。
The meiotic behavior of pollen mother cells (PMCs) from apomictic cymbidium ramie (2n = 42) and sexual reproduction Platycladus orientalis ramie (2n = 28) were compared to deduce the evolutionary relationship between the two. To explore the cytogenetic basis of B.tricuspis in apomictic reproduction and to provide a theoretical basis for the genetics research of apomixis. During the meiosis of PMC induced by apomictic genotypes, abundant trivalent forms were found, belonging to the typical autotriploid meiosis behavior. The number of reproductive type PMC The vast majority of normal splittism, but there are also a small number of anomalies. Some of these abnormalities may be closely related to the formation of unreduced gametes (2n). Thus, it is inferred that the fusion of unreduced gametes (2n) and meiotic gametes (n) may occur in the reproductive process of sexual reproduction and produce homotrimer zygotes, which should be apomixis Leaf ramie important cytogenetic basis.