论文部分内容阅读
二倍体野菊与栽培菊种间杂交常不能结实,从而严重影响了野菊优异基因的利用,为了揭示其原因,以栽培菊(Dendranthema grandiflorum)‘金陵黄玉’为母本,二倍体野生菊甘菊(D.lavandulifolium)为父本,开展了种间杂交,测定了父本花粉活力,研究了授粉后花粉在柱头萌发行为及胚胎发育情况等。结果发现,父本甘菊的花粉活力在授粉时为11.2%,人工授粉4h内未观察到柱头上有花粉萌发;授粉后8h时平均每个柱头上只有7.5粒花粉萌发;到授粉后12h时数量达到最多,为16.1粒;随后数量急剧下降,到24和48h时柱头萌发花粉数量分别只有3.2粒和2.4粒,且大部分花粉管生长异常并停留在柱头表面。此外,在授粉8d后观察到12.0%子房中含有正常的球形胚,但之后就未观察到正常胚胎,最终未获得杂交种子,而母本自然开放结实率高达42.3%。以上结果表明,受精前、后的生殖障碍,即母本柱头上花粉萌发数量少且萌发异常和受精后胚胎大量败育,是引起种间杂交不结实的主要原因。
Diploid wild chrysanthemum and cultivated hybrids often can not be strong hybrids, which seriously affected the wild chrysanthemum genes use, in order to reveal the reason, to cultivate chrysanthemum (Dendranthema grandiflorum) ’Jinling topaz’ as female, diploid wild chrysanthemum D.lavandulifolium was used as the male parent to carry out interspecific hybridization. The male pollen viability was measured and the pollen germination behavior and embryo development after pollination were studied. The results showed that the pollen viability of Papaveraceae was 11.2% at pollination, no pollen germination was observed on stigma within 4h after pollination; only 7.5 pollen germinated on stigma at 8h after pollination; at 12h after pollination The number reached the maximum of 16.1; then the number dropped sharply, by the time of 24 and 48h, the number of germination pollens were only 3.2 and 2.4, respectively, and most of the pollen tubes grew abnormally and remained on the stigma surface. In addition, 12.0% of the ovary was observed to contain normal globular embryos 8 days after pollination, but no normal embryos were observed after that. Hybrid seeds were not obtained in the end, but the natural open seed set rate of the female parent was 42.3%. The above results show that, before and after fertilization, reproductive disorders, that is, the mother of the stigma pollen germination on the number of small and abnormal germination and fertilization after a large number of abortion embryos, is caused by interspecific hybridization is not the main reason.