Cytogenetic Analysis of Cantaloupe, Netted, and Hami Melons

Chromosome identification is essential in cytogenetic studies. Knowledge about cytogenetic traits, genome sizes, and nuclear DNA content determination is required in modern plant breeding. This study’s objective was to examine the chromosome count, chromosomal karyomorphological features, 5S and 18S rDNA loci distribution, chromosome length, centromere positions, genome sizes, and the 2C-DNA content of cantaloupe, netted, and Hami melons. The three melon varieties had 24 chromosomes each, and the total chromosome lengths were 28.5, 34.05, and 35.02 µm for cantaloupe, netted, and Hami melons, respectively. Fluorescent in situ hybridization revealed that the three varieties had two 5S rDNA loci, cantaloupe and Hami melons had four 18S rDNA loci, and the netted melon had six 18S rDNA loci. The 2C DNA content of three melons was confirmed by flow cytometry. The estimated DNA contents were 1.15 pg, 1.18 pg, and 1.11 pg for cantaloupe, netted and Hami melon respectively. This study’s findings will inform further cytogenetic studies of the examined melon varieties and facilitate improved breeding programs.