Abstract: 【Objective】Selection of primary trisomics of the cabbage（Brassica oleracea L. var.capitata L.）is an important foundation for the gene chromosome mapping and other genetic studies. 【Method】 The self fertilization line - 9601 of cabbage was used as material, by using analysis of the root tip cell chromosome number and pollen mother cell chromosome number identification and karyotype, the primary trisomics from the progenies of 3x × 2x in the cabbage were selected. 【Result】Many aneuploid plants with one or two extra chromosomes were obtained and a set of primary trisomics (Tr-1, Tr-2, Tr-3, Tr-4, Tr-5, Tr-6, Tr-7, Tr-8 and Tr-9 in which the Tr-1 and Tr-4 from 2n+2 plants, others from 2n+1 plants ) was acquired from the aneuploid plants. Each trisomic was with some unique characters, such as plant height, plant type, leaf type, size of flower bud and inflorescence.【Conclusion】The triploid crossing by the diploid is a convenient and effective way to select trisomics in cabbage.

Key words: Cabbage (Brassica oleracea L. var. capitata L.), Trisomics, Karyotype analysis