Effect of Mutagens on Frequency and Spectrum of Viable Mutations in Horsegram (Macrotyloma uniflorum (Lam.) Verdc)

Abstract

The seeds of horsegram (Macrotyloma uniflorum (Lam.) Verdc) cv. Dapoli Kulthi1 were subjected to gamma radiation (100, 200, 300 and 400Gy), EMS (0.2, 0.3, 0.4 and 0.5 %) and combination treatments. The mutations affecting gross morphological changes in plant habit, leaf and pod morphology, and maturity were scored as viable mutations. These mutants were characterized and named on the basis of specific characters constantly observed in them throughout the course of investigation. Effect of mutagens on the frequency and spectrum of different types of viable mutations in M2 generation were recorded. The high frequency of mutations in terms of mutants per 1000 M2 plant population was observed in low doses of EMS (0.2%), gamma radiation (100Gy) as well as in their combination (400Gy +0.4% EMS). The range of viable mutations in gamma radiation, EMS and their combinations was 0.61 to 2.16%, 0.62 to 2.98% and 0.21 to 1.81% respectively. Spectrum of viable mutations included desirable characters like early maturity, tall and dwarf habit, profuse branching, increased leaf area, higher number of pods, grains and grain weight were used to select desirable mutants.