Isolation of High Yielding Early Mutants of Sesame (Sesamum indicum L.) Based on the Relationship Between Traits Governing Yield and Earliness

Abstract

Sesame is a leading oilseed crop known for its quality edible oil and byproducts. Mutation breeding is an effective means of creating new genetic variability as certain desirable traits like uniform maturity, non-shattering capsules etc., do not exist in nature..The present study aimed to isolate high yielding early mutants of sesame on the basis of relationship between traits governing yield and earliness. Gamma-ray doses of 300 Gy, 350 Gy, and 400 Gy and combination treatments of gamma-ray + EMS: 300 Gy + 10 mM, 350 Gy + 10 mM, and 400 Gy + 10 mM were used in this study. In M2 generation, putative mutants with high yield and earliness were isolated and characterized individually to study the nature of the association of traits with single plant yield in early maturing lines. Two traits viz., increased height at the beginning of flowering and reduced days to the beginning of flowering were found to have a favorable effect on reducing crop period and increasing single plant yield. Therefore, these two traits should be used as a criterion for selection for achieving high yield with earliness in sesame. In addition, the ‘tri-leaf’ characteristic observed in the putative ‘early mutants’ led to increased single plant yield. Early lines of sesame with high yield and uniform maturity can enable mechanical harvesting in future sesame cultivation. The selected mutants may be forwarded to further generations and utilized in sesame breeding.