Effect of mutagens on character association in sesame (sesamum indicum l.)

Three diverse sesame genotypes viz., Rama, SI 1666 and IC 21706 were treated with both physical (gamma-rays) and chemical (EMS) mutagens separately. Three doses of gamma-rays (200 Gy, 400 Gy and 600 Gy) and four doses of EMS (0.5%, 1.0%, 1.5% and 2.0%) were applied to each of the three genotypes. Correlation coefficients of morphological characters were computed in M3 generation, while in M4 generation biochemical characters namely oil, fatty acids and protein were subsumed in correlation study along with seed yield. The correlation coefficients in M3 generation evinced that plant height, number of branches per plant, capsules per plant, capsule length and number of seeds per capsule were important yield components in the mutants. Suggestion has been made to accentuate these five characters during selection in M3 generation. Correlation coefficients between seed yield and biochemical characters in M4 generation revealed that mutation refurbished association of seed yield with linoleic acid, stearic acid, palmitic acid and between linoleic acid and oleic acid, linoleic acid and palmitic acid, stearic acid and oleic acid from negative (control) to positive direction. Along with seed yield, oil content, oleic acid and linoleic acid were epitomized to be considered as important selection criteria for evolving high yielding variety with more oil content and good oil profile in mutant population. (author)