Effect of Short Duration EMS Treatments on the Frequency and Spectrum of Induced Mutations in Greengram

Abstract

Two greengram (Vigna radiata (Wilczek)) varieties, viz., DT-9-E and TT-9-E, were treated with 0.25% EMS for a period of one hour under reduced atmospheric pressure after pre-soaking the seeds from 11:00 to 13:00 hours at half-hour intervals. The M₁, M₂ and M₃ generations were grown in the field, and macro-mutants were selected from the latter two generations. The M₃ generation showed a higher frequency and broader spectrum of mutations than the M₂ generation. A wider spectrum of chlorophyll, foliar and agronomic mutations was observed in treatments involving different periods of pre-soaking, indicating the time dependence of different loci for replication. EMS induced more agronomic mutations than chlorophyll and foliar mutations. Maturity in greengram appeared to be controlled by two groups of genes, one tending towards earliness and the other towards lateness.