Nuclear genome of Musa is relatively small (1Cx ~ 550 - 750 Mbp) and divided to 1-2 μm long and morphologically similar chromosomes. This makes cytogenetic studies difficult and there is no reliable method to identify all chromosomes within a karyotype and discriminate parental chromosomes in a hybrid. The paucity of chromosome-specific landmarks and markers hampers studies on karyotype evolution and chromosome behavior in hybrids. One of the best cytogenetic landmarks are repetitive units organized in tandems. Large blocks of satellite DNAs are typically observed in heterochromatic regions of chromosomes and are usually located in centromeric or telomeric regions. Chromosome loci rich in satellite DNA usually show specific banding pattern and this makes them useful cytogenetic markers to discriminate individual chromosomes. The presence of chromosome landmarks enables identification of individual chromosomes and is a prerequisite to study structural changes accompanying evolution and speciation and to follow chromosome behavior and transmission in interspecific hybrids.
