Abstract: The chromosome number and karyotype of Allamanda neriifolia were studied using immature embryos as experimental materials. The results showed that the embryo cells normally contain 9 pairs of chromosomes, and all chromosomes were metacentric or submetacentric chromosomes. The karyotype formula was 2n=2x=6sm+12m. The karyotype was 2A type, and the asymmetry index was 58.95%.

Key words: Allamanda neriifolia, chromosome, karyotype

摘要： 以硬枝黄蝉Allamanda neriifolia幼胚为试验材料，对其体细胞染色体进行计数与核型分析。结果表明，硬枝黄蝉幼胚细胞含9对染色体，由中部或近中部着丝粒染色体构成。核型公式为2n=2x=6sm+12m。核型不对称系数为58.95%，核型分类属于2A型。

关键词: 硬枝黄蝉, 染色体, 核型分析