Physical Mapping of the 18S-26S rDNA by Fluorescent in situ Hybridization (FISH) in Two Species of Camellia (Theaceae)

摘要

The distribution of the 18S-26S rDNA on the chromosomes of Camellia yunna-nensis and C. japonica was investigated by fluorescent in situ hybridization ( FISH). The advanced method was used for preparing chromosome spreads. Four 18S-26S rDNA loci including three major sites and one minor site were detected in the genome of each species. And the results also revealed some differentiation between them. Both the species had close relationship with polyploidy C. reticulata Lindl. Implications of the results in understanding the origin of polyploid C. reticulata are discussed.