Using the genomic DNAs of maize and rice as probes respectively, the homolo
gy of maize and rice genomes was assessed by genomic in situ hybridization.
When rice genomic DNAs were hybridized to maize, all chromosomes displayed
many multiple discrete regions, while each rice chromosome delineated a si
ngle consecutive chromosomal region after they were hybridized with maize g
enomic DNAs. The results indicate that the genomes of maize and rice share
high homology, and confirm the proposal that maize and rice are diverged fr
om a common ancestor.