Abstract:The karyotypes and G-banding patterns of four kinds of experimental materials collected from different geographic regions were compared in Oryza rufilpogon Griff. There were obvious polymorphisms in chromosome arm length,arm ratio,
G-band number of each arm as well as the size and degree of G-bands staining among the experimental materials. The single
band of some chromosomes is heteromorphic in the size and staining intensity. The mechanisms of karyotype polymorphism
formation is also discussed.