Numerical chromosomal aberrations and their correlation with the extent of nucleolar variations was studied in seven commercial hybrids of sugarcane of subtropical India. Extensive chromosome mosaicism (2n = 92–126) and wide variation with respect to nucleolus number per cell (1–8) was observed in these clones. Numerical Aberration Factor (NAF) has been suggested to ascertain the extent of somatic chromosome variation in mosaic genotypes. The NAF value was highest in the old elite clone Co 1148. The regression analysis of NAF value on nucleoli variation per cell showed a linear relationship (r = 0.65) indicating that, intra-clonal heterogeneity of chromosome number has a direct influence (to a certain limit) on extensive nucleolar variations present in these clones.
Sugarcane, chromosome mosaicism, mitosis, nucleoli variation, Numerical Aberration Factor (NAF)
