Senna is a diverse and paraphyletic genus in the subfamily Caesalpinioideae (Fabaceae Lindl.) comprising various species of industrial and medicinal value. To date, the genome-based taxonomic relationship among several Senna species remains enigmatic. Cytogenetic information is invaluable in deciphering phylogenetic relationships and evolutionary history. However, insufficient chromosomal research for many Senna species impedes comparative cytotaxonomic analyses aimed at understanding their genomic evolution. To provide additional Senna-related molecular cytogenetic information, we karyotyped 11 Senna species by employing triple-color fluorescence in situ hybridization using 5S rDNA, 45S rDNA, and Arabidopsis thaliana-type telomeric pre-labeled oligonucleotide probes. Chromosome numbers were predominantly 2n = 28, but 2n = 22 (S. marilandica) and 2n = 24 (S. uniflora) were also observed. While most species revealed only one interstitial 5S rDNA locus, except for S. uniflora which has two loci, a range of one to three 45S rDNA loci were detected at distal chromosomal regions. Additionally, we observed a hemizygous 45S rDNA locus in S. auriculata. In addition to chromosome termini, weak signals for telomeric repeats were found in interstitial regions in S. hirsuta, S. corymbosa, and S. alexandrina. These cytogenetic data can be integrated with molecular phylogenetic data for more comprehensive Senna cytotaxonomic analyses.

番泻叶是 Caesalpinioideae (Fabaceae Lindl.) 亚科中的一个多样化和并系群属，包括各种具有工业和药用价值的物种。迄今为止，几种番泻树物种之间基于基因组的分类关系仍然是个谜。细胞遗传学信息在破译系统发育关系和进化历史方面是无价的。然而，许多番泻叶物种的染色体研究不足阻碍了旨在了解其基因组进化的比较细胞分类学分析。为了提供额外的塞纳-相关分子细胞遗传学信息，我们核型11种塞纳通过使用5S rDNA的，45S rDNA的采用三色荧光原位杂交的物种，和拟南芥型端粒预标记寡核苷酸探针。染色体数目主要为 2 n  = 28，但也观察到2 n  = 22 ( S. marilandica ) 和 2 n  = 24 ( S. uniflora )。虽然大多数物种仅显示一个间质 5S rDNA 基因座，除了具有两个基因座的S. uniflora，在染色体远端区域检测到 1 到 3 个 45S rDNA 基因座。此外，我们在S. auriculata 中观察到半合子 45S rDNA 基因座。除了染色体末端外，在S. hirsuta、S. corymbosa和S. alexandrina 的间隙区域中还发现了端粒重复的微弱信号. 这些细胞遗传学数据可以与分子系统发育学数据相结合，以进行更全面的番泻叶细胞分类学分析。