Mutagenic effects on meiosis in legumes and a practical case study of Vicia faba L.

Abstract

Mutagens typically physical (ionising radiations, e.g. particulate (α-ray, β-ray and thermal neutrons) and non-particulate (X-ray and γ ray); non-ionising radiation, e.g. UV ray) and chemical (EMS, dES, NMG, MMS, EO, hydroxyl amine, nitrous acid, 5-bromouracil, 2-aminopurine and ethidium bromide, among others) are widely used in plant species of interest with an objective to create genetic variations by widening the gene pool and to induce gene mutation of commercial importance (superior qualitative trait(s) and enhancement in raw and value-added product(s)). Gene mutation is of global significance, and successful mutagenesis experiment depends on the sensitivity of the genotype(s) to the administered doses of the mutagen(s) employed. Assessment of LD50, lethality, injury, mitotic and meiotic aberration frequency (key components to determine sensitivity of a species) is prerequisite for determining sublethal doses for monitoring successful mutation breeding experiments. The chapter gives a comparative observation of ethyl methane sulphonate (EMS), methyl methane sulphonate (MMS) and gamma irradiation on cytological and developmental parameters, i.e. meiotic features, pollen sterility, seed germination and seedling survival in Vicia faba L. The present study on the Vicia faba L. var. minor and major in M1 generation showed that all the mutagens used elicit numerous chromosomal aberrations in meiosis and decrease in seed germination, pollen fertility and seedling survival. The combined treatments induced more chromosomal aberrations than the individual doses of mutagens which represents that combined treatments could be more effective in creating more favourable variability than individual doses in both the varieties, i.e. minor and major of Vicia faba L.