Abstract: Using the common slice-making method, the karyotype as well as chromosomes in embryogenic callus of Quercus variabilis were analyzed.The results showed that the chromosome complement of 2n=2x=24. The karyotype formula was K(2n)=2x=24=20m+4sm. It is belong to “2B” category of STEBBINS. The total length of chromosome set was 18.55 μm. By analyzing chromosomes of embryogenic callus tissue cells with eight months continuous subculture demonstrated that the mumber and structure of chromosome were relatively steady, in which diploid cell occupied 97.2%, tetraploidy cell 1.87%, haploidy cell 0.93%. Aneuploids and chromosomes structure variation were not found. Nuclei in some meristematic cells derived from subsurface layer of hypocotyl of somatic embryos were lamellar or elliptic. Trinuclear cell was found in mature somatic embryos occasionally.

Key words: Quercus variabilis, karyotype, somatic embryogenesis, cytology