【摘要】 柿属植物兼具药用与经济价值，开发潜力巨大，然而其细胞学与分子生物学基础研究仍较薄弱。解析柿属植物的倍性和基因组大小，将为绘制全基因组图谱、阐明亲缘关系及加速遗传育种进程提供关键的细胞遗传学依据。以老鸦柿根尖为材料，通过常规压片与卡宝品红染色进行染色体核型分析；综合采用K-mer分析与流式细胞技术，对老鸦柿、乌柿、君迁子、柿、油柿共5种柿属植物的倍性及基因组大小进行测定。结果显示：老鸦柿染色体数目为2n=4x=60,核型公式为20m+36sm+4st,未观察到随体，确认其为四倍体，染色体基数为x=15;4条为近端部着丝点染色体，36条为近中部着丝点染色体，20条为中部着丝点染色体。K-mer分析结果支持该结论，并预测其基因组大小为3.04 Gb,杂合率为3.40%。流式细胞术进一步揭示了所研究物种间存在显著的多样性：乌柿为九倍体、柿为六倍体、老鸦柿为四倍体、君迁子和油柿为二倍体；其基因组大小分别为6.60、2.89、2.79、1.50 Gb及1.53 Gb。更多还原

【Abstract】 The genus Diospyros possesses significant medicinal and economic value, with vast potential for development.However, its basic research in cytology and molecular biology remains relatively weak.Analyzing the ploidy and genome size of Diospyros plants will provide a key cytogenetic basis for mapping whole genomes, elucidating phylogenetic relationships, and accelerating genetic breeding processes.In this study, root tips of D.rhombifolia were utilized to analyze the karyotype of chromosomes through tissue sectioning and carbol fuchsin staining techniques.The ploidy and genome size of 5 Diospyros species were predicted using the K-mer approach and flow cytometry techniques, including D.rhombifolia,D.cathayensis,D.lotus,D.kaki,and D.oleifera.Karyotype analysis showed that the chromosome number of D.rhombifolia was 2n=4x=60,and the karyotype formula was 20m+36sm+4st without satellites.It was a tetraploid plant with a base chromosome number of 15.The chromosome complement consisted of 4 subtelocentric chromosomes, 36 submetacentric chromosomes, and 20 metacentric chromosomes.K-mer analysis results supported this conclusion, predicting a genome size of 3.04 Gb and a heterozygosity rate of 3.40% for D.rhombifolia.Flow cytometry further revealed significant ploidy diversity among the 5 species: D.cathayensis was nonaploid, D.kaki was hexaploid, D.rhombifolia was tetraploid, and D.lotus and D.oleifera were diploid.The genome sizes of these species were 6.60 Gb, 2.89 Gb, 2.79 Gb, 1.50 Gb, and 1.53 Gb, respectively.This study systematically reported the karyotype characteristics and genome size of D.rhombifolia and uncovered widespread ploidy variation among Diospyros species.These results provide important genomic information for enriching the genetic database, reconstructing the evolutionary history, and advancing molecular breeding practices in Diospyros.更多还原