In chrysanthemum, breeders seek for desirable characteristics of the inflorescence, which can first be established once the plant is mature. The present study aims to determine whether measurement of DNA content can be useful in the detection of somaclonal variants and/or separation of chimera components in chrysanthemum at the early in vitro multiplication stage. Eleven Chrysanthemum × morifolium (Ramat.) Hemsl. cultivars of the Lady group (a mother cultivar and ten of its radiomutants obtained by X-ray- or γ-irradiation; solid and periclinal chimeras) were propagated in vitro. Single-node explants were cultured in Murashige and Skoog (MS) medium, either without plant growth regulators (PGRs) or supplemented with 6-benzyladenine (BA) and indole-3-acetic acid (IAA). The nuclear DNA content was measured by flow cytometry (FCM) in the shoots produced in vitro. After acclimatization and growth of the plants in a glasshouse, inflorescence colour was recorded. The addition of PGRs to the medium almost doubled the mean number of shoots produced in vitro per explant, but caused a change in inflorescence colour of all (‘Lady Apricot’; periclinal chimera) or part of the plants (‘Lady Amber’; solid mutant and ‘Lady Salmon’; periclinal chimera). All radiomutants contained less DNA than the mother cultivar ‘Richmond’. There were significant differences in DNA content between plants of the same cultivar grown in media with or without PGRs for ‘Lady Apricot’ and ‘Lady Salmon’, but no phenotype alternation occurred in chrysanthemums produced in PGR-free medium compared to the original cultivars. Conversely, in medium with PGRs, chimeras produced flowers different from the original colour. In all except one cultivar (‘Lady Amber’; solid mutant) a lack of differences in genome size between plants grown in either medium coincided with a stable inflorescence colour. The occurrence of some plants of ‘Lady Amber’ with different inflorescence colour may be due to small DNA changes, undetectable by FCM. It can be concluded that FCM analysis of DNA content in young plantlets can be indicative of the stability of inflorescence colour in chrysanthemum, especially chimeric cultivars, and for mutant detection.

在菊花中，育种者寻求花序的理想特性，一旦植物成熟，就可以首先建立该特性。本研究旨在确定DNA含量的测量是否可用于体外增殖早期阶段菊花的体细胞克隆变异体和/或嵌合体成分的分离。十一菊花 ×  rif（Ramat。）Hemsl。在体外繁殖了Lady组的一个品种（一个母亲品种及其通过X射线或γ射线辐照获得的十个辐射突变体；固体和周缘嵌合体）。在没有植物生长调节剂（PGR）或补充有6-苄腺嘌呤（BA）和吲哚-3-乙酸（IAA）的Murashige和Skoog（MS）培养基中培养单节点外植体。通过流式细胞仪（FCM）测量体外产生的芽中的核DNA含量。在温室中使植物适应和生长后，记录花序颜色。向培养基中添加PGR几乎使每个外植体在体外产生的平均芽数增加了一倍，但导致所有植物（“杏子”；周缘嵌合体）或部分植物（“琥珀色”；固体）的花序颜色发生变化。突变体和“淑女鲑鱼”；周缘嵌合体）。所有的放射性突变体所含的DNA均少于其母亲品种“里士满”。在有或没有PGR的'Lady Apricot'和'Lady Salmon'培养基中生长的相同品种的植物之间，DNA含量之间存在显着差异，但是与原始品种相比，在无PGR的培养基中产生的菊花没有发生表型改变。相反，在带有PGR的培养基中，嵌合体产生的花与原始颜色不同。除了一种栽培品种（“ Lady Amber”；固体突变体）外，在任何一种培养基中生长的植物之间基因组大小的差异均缺乏，并伴有稳定的花序色。一些具有不同花序颜色的“琥珀色女士”植物的出现可能是由于DNA的微小变化，FCM无法检测到的。