An essential, but still not fully understood, aspect of angiosperms’ reproduction is the issue of callose deposition during early female reproductive processes in sexual and apomictic taxa. It was believed that callose may be a marker for an early identification of the reproduction mode and lack of callose was suggested as characteristic for apomicts. However, our findings clearly prove that meiotic diplospory of the Taraxacum type is accompanied by callose deposition and show that lack of callose is not an obligatory feature of the apomictic reproduction mode. In young ovules of C. brevirostris, callose was a marker of the cell entering the first meiotic division restitution. Synthesis and degradation of callose followed a strictly defined pattern, which differed from that described in the majority of analyzed angiosperms. Callose deposition began at the micropylar pole of the diplosporous megaspore mother cell and, finally, this cell wall polysaccharide showed a bipolar location. This pattern dynamically changed in the later stages of meiotic diplospory and, like in sexual species, it was related to the selection of the functional megaspore. Thus, it seems that callose can play a similar regulatory function in cell-cell communication between somatic tissues and the reproductive precursor cell in the ovules of both sexual and diplosporous taxa.

被子植物繁殖的一个基本但仍未完全了解的方面是性和无融合生殖分类群中女性早期生殖过程中的call质沉积问题。据认为call质可能是早期鉴定生殖方式的标志物，提示缺乏of质是无融合生殖的特征。但是，我们的发现清楚地证明，蒲公英型减数分裂双孢子虫伴随着call的沉积，并表明缺乏of不是无融合生殖模式的必然特征。在短隐孢子虫的胚珠中，call质是进入第一次减数分裂分裂恢复的细胞的标志。ose的合成和降解遵循严格定义的模式，这与大多数分析的被子植物中描述的模式不同。愈伤组织的沉积开始于双孢子状大孢子母细胞的毛孔极，最后，该细胞壁多糖显示出双极位置。这种模式在减数分裂双孢子虫的后期动态变化，并且与有性物种一样，与功能性大孢子的选择有关。因此，似乎愈伤组织可以在有性和双孔类群的胚珠中的体细胞组织与生殖前体细胞之间的细胞间通讯中发挥类似的调节功能。