Abstract: This paper investigates the chromosome numbers and karyotypes of two species of Dieffenbachia . The result shows that the karyotype formula of D. daguensis is K (2n ) = 2x = 34 = 12m + 18sm+ 4st , which is of 3B type with As·K% = 66.52% ; the karyotype formula of D. maculata is K (2n ) = 2x = 34 = 2M+ 28m + 4sm, which is of 1B type withAS·K% = 55.38% . Compared with the more advanced members in Typhonium and Sauromatu, the karyotype of Dieffenbachia is rather primitive, and the karyotypes of Araceae are rather diverse .

Key words: Dieffenbachia daguensis

摘要： 报道了天南星科(Araceae ) 花叶万年青属( Dieffenbachia) 两种植物染色体数目及核型, 革叶万年青( D. daguensis) 品种绿帝皇的核型公式为K ( 2n ) = 2x = 34 = 12m + 18sm + 4st , 核型类型为“3B”, 核型不对称系数As·K% = 66. 52%。花叶万年青( D. maculata) 品种粉黛叶的核型公式为K (2n ) = 2x = 34 = 2M+28m+ 4sm, 核型类型为“1B”, 核型不对称系数为AS·K% = 55. 38%。与同科的较进化的犁头尖属和斑龙
芋属比较, 花叶万年青属植物的核型较原始些, 且天南星科植物的核型极其多样化。

关键词: 革叶万年青, 花叶万年青, 染色体, 核型FONT