Genetic Variability on Tolerance of Maize ( Zea mays L.) Genotypes Induced with Sodium Azide Mutagen

Abstract

The polyploidy expressions of colchicine mutagen at concentrations of 0.05%, 0.1%, 0.15%, 0.2%, 0.3%, 0.5% and 0.7% were investigated on maize genotypes. The in-vitro and field experiments were carried out at the Genetics and Molecular Biology laboratory and Research Farm of the Department of Botany, University of Ibadan, Nigeria. The concentration and genotype had significant (p ˂ 0.05) effect on percentage emergence, though increased concentration showed a lethal effect on DTSR-WC and SAMMAZ19S-14 DRD genotypes. The mutagen showed significant lethal effect on the percentage emergence of plants as the concentration of colchicine increased. SAMMAZ19S-14 DRD at 0.15% and TZECOMP3C2 at 0.1% showed higher ploidy with high coefficient of variation of 4.36 and 4.38. However, ACR.91.SUWANI-SRC exhibited mixoploid at 0.1% concentration of colchicine though, remained unaffected by other concentrations, but found to be more tolerant genotype to mutagenic effect.