Determination of DNA content and relative 2C genome sizes of some promising commercial varieties of sugarcane using flow cytometer

Abstract

In this study, 2C deoxyribonucleic acid (DNA) content and the genome sizes (in pictograms [pg] and megabase pairs [Mbp], respectively) of 19 promising commercial varieties of sugarcane, the derivatives of man-made interspecific hybrids between cultivated and wild species were analyzed using flow cytometry. In this work, 2C nuclear DNA content was determined. Knowing the 2C nuclear DNA content, the unknown chromosome numbers of the varieties could be predicted. Large differences (65% variation) in DNA content (2C) of 19 varieties were detected, ranging, from 3.80 to 10.96 pg, which corresponds to a genome size ranging from 3724.00 to 10740.80 Mbp due to the variation of ploidy level and are considered the most complex genomes among crop plants. However, the relationship between chromosome number and genome size was highly significant (P < 0.001). In this study, internode diameter, sugar juice content and cane yield/ha are also positively correlated with DNA content. The estimated genome sizes would also yield information critical for sugarcane breeding and genome sequencing programs.