A total of 120 nodal segments of Chrysanthemum ‘Gongju’ plantlets were treated with colchicine to obtain autopolyploidy. Flow cytometry showed that 1 of the 12 surviving seedlings had DNA contents that were twice that of tetraploid plants. Microscopy revealed that the epidermal cell and stomatal area of octoploid plant leaves were larger than those of tetraploid plant leaves. Morphological characteristics showed that the plant height of octoploid plants did not differ from that of tetraploid plants, but their leaves and flowers remarkably varied. The leaves and flowers of octoploid plants were larger than those of tetraploid plants. The diameters of the inflorescence and disc flower of octoploid plants increased by 7.2% and 28.4% compared with those of tetraploid plants, respectively. Similarly, the numbers of their ligulate and tubular flowers increased by 22.6% and 34.0% compared with those of tetraploid plants, respectively. Semi-lethal temperature (LT50) of tetraploid plants was − 8.58 °C, while LT50 of octoploid plants decreased by 3.4 °C. At low temperatures, the relative expression levels of CmICE, CmDREB, CmCOR, CmPYR1, CmFAD, CmWRI, CmBAM, and CmPSP genes related to cold resistance in octoploid plants were higher than those in tetraploid plants. Conversely, the expression levels of CmAPX and CmGSH in octoploid plants were lower than those in tetraploid plants. The relative expression levels of CmOST, CmPDH, and CmOAT did not differ between octoploid and tetraploid plants.

中文翻译：

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菊花中的同源多倍体。'Gongju' 提高耐寒性

用秋水仙素处理菊花'工菊'小植株的总共120个节段以获得同源多倍体。流式细胞术显示，12 株幸存的幼苗中有 1 株的 DNA 含量是四倍体植物的两倍。显微镜观察发现八倍体植物叶片的表皮细胞和气孔面积大于四倍体植物叶片的表皮细胞和气孔面积。形态学特征表明，八倍体植物的株高与四倍体植物的株高无差异，但叶、花差异显着。八倍体植物的叶和花比四倍体植物的叶和花大。与四倍体植物相比，八倍体植物的花序和花盘直径分别增加了7.2%和28.4%。相似地，与四倍体植物相比，它们的舌状花和管状花的数量分别增加了22.6%和34.0%。四倍体植物的半致死温度 (LT50) 为 − 8.58 °C，而八倍体植物的 LT50 降低了 3.4 °C。在低温条件下，八倍体植物抗寒相关基因CmICE、CmDREB、CmCOR、CmPYR1、CmFAD、CmWRI、CmBAM和CmPSP的相对表达量高于四倍体植物。相反，CmAPX和CmGSH在八倍体植物中的表达水平低于四倍体植物。CmOST、CmPDH 和 CmOAT 的相对表达水平在八倍体和四倍体植物之间没有差异。而八倍体植物的 LT50 降低了 3.4 °C。在低温条件下，八倍体植物抗寒相关基因CmICE、CmDREB、CmCOR、CmPYR1、CmFAD、CmWRI、CmBAM和CmPSP的相对表达量高于四倍体植物。相反，CmAPX和CmGSH在八倍体植物中的表达水平低于四倍体植物。CmOST、CmPDH 和 CmOAT 的相对表达水平在八倍体和四倍体植物之间没有差异。而八倍体植物的 LT50 降低了 3.4 °C。在低温条件下，八倍体植物抗寒相关基因CmICE、CmDREB、CmCOR、CmPYR1、CmFAD、CmWRI、CmBAM和CmPSP的相对表达量高于四倍体植物。相反，CmAPX和CmGSH在八倍体植物中的表达水平低于四倍体植物。CmOST、CmPDH 和 CmOAT 的相对表达水平在八倍体和四倍体植物之间没有差异。CmAPX和CmGSH在八倍体植物中的表达水平低于四倍体植物。CmOST、CmPDH 和 CmOAT 的相对表达水平在八倍体和四倍体植物之间没有差异。CmAPX和CmGSH在八倍体植物中的表达水平低于四倍体植物。CmOST、CmPDH 和 CmOAT 的相对表达水平在八倍体和四倍体植物之间没有差异。