Cultivated caladiums (Caladium × hortulanum Birdsey) are popular ornamental plants. Although somaclonal variation occurs frequently in caladium during tissue culture, little research has been conducted on obtaining and detecting variants from long-term callus cultures. Herein, plants were regenerated from ‘Red Flash’ caladium calluses subcultured for approximately 40 mo, and 116 out of 520 established plants were grouped into 14 somaclonal variation types based on their morphological differences. Nuclear DNA content of six types (SVT1, SVT2, SVT4, SVT5, SVT8, and SVT10) varied from − 1.08% to 0.33% compared with the wild type, and these variants shared a similar chromosome number to the wild caladium (2n = 2x = 30). Three types (SVT3, SVT7, and SVT9) containing 2.82 to 5.42% less nuclear DNA content was the result of losing one or two chromosomes, and one type (SVT6) with significantly lower cellular DNA content was due to losing four chromosomes. Four types (SVT11–SVT14) contained 85.16 to 101.52% more DNA content and the SVT12 and the SVT13 had a double number of chromosomes (2n = 4x = 60), while the SVT11 and SVT14 had four more chromosomes and six less chromosomes as compared with a typical tetraploid, respectively. Correlation analysis suggested that leaf thickness, leaf index, and stomatal characteristics could be used as indicators of plant ploidy in caladium. A wide variation of pigment content was found among the variation types, and the content of chlorophyll, flavonoid, and anthocyanin had a significant positive correlation with the color parameters a* and b*. Leaf color variants created by prolonged in vitro callus cultures might hold great promise for caladium breeding.

栽培钙（Caladium×hortulanum Birdsey）是流行的观赏植物。尽管组织培养期间钙的体细胞克隆变异频繁发生，但是关于从长期愈伤组织培养物中获得和检测变异的研究很少。在此，从传代培养约40 mo的'Red Flash'愈伤组织中再生出植物，并根据其形态差异将520个已建立植物中的116个分类为体细胞克隆变异类型。与野生型相比，六种类型（SVT1，SVT2，SVT4，SVT5，SVT8和SVT10）的核DNA含量从− 1.08％到0.33％不等，并且这些变体具有与野生钙类似的染色体编号（2 n  = 2倍 = 30）。丢失1或2条染色体的结果是3种类型（SVT3，SVT7和SVT9）的核DNA含量减少了2.82％至5.42％，而丢失了1条或2条染色体的一种类型（SVT6）是由于丢失了4条染色体。四种类型（SVT11–SVT14）的DNA含量增加了85.16至101.52％，并且SVT12和SVT13的染色体倍数（2 n  = 4 x = 60），而SVT11和SVT14的染色体分别比典型的四倍体多四个和六个少。相关分析表明，叶片厚度，叶片指数和气孔特征可以用作钙中植物倍性的指标。在变化类型中发现色素含量变化很大，叶绿素，类黄酮和花色苷的含量与颜色参数a *和b *呈显着正相关。长时间的体外愈伤组织培养产生的叶片颜色变异可能为钙育种带来很大希望。