Spectrum and Frequency of Chlorophyll Mutations Induced by MMS, Gamma Rays and Their Combination in Two Varieties of Vicia faba L.

A comparative study of the frequency and spectrum of chlorophyll mutations induced by MMS (0.01, 0.02, 0.03, 0.04 and 0.05%), gamma rays (5, 10, 20, 30 and 40 kR) and their combinations (10 kR+0.01%, 10k R+ 0.02%, 10 kR+0.03%, 10 kR+0.04% and 10 kR+0.05%) in M2 generation was made in 2 varieties of Vicia faba L. viz., minor and major. Six different types of chlorophyll mutants viz., albina, chlorina, maculata, tigrina, virescence and xantha were identified in the treated populations. Chlorophyll mutation frequency was calculated on plant population basis. Frequency of chlorina mutants was highest followed by xantha and other types in both the varieties. Combination treatments in general proved to be most effective followed by MMS and gamma rays in inducing maximum frequency of chlorophyll mutations (Gamma rays + MMS> MMS> Gamma rays). A significant variation in varietal response was observed. The co-efficient of interaction was less than additive, but synergistic effect was also observed.