Assessment of genetic variability and association among yield traits in M₂ population of menthol mint cv. Kosi

Menthol mint, is a perennial herbaceous aromatic plant cultivated as an annual for its commercially valued essential oil. The plant is highly heterozygous in its genetic constitution and vegetatively propagated by stolons, making it a promising material for inducing mutation to create variability. Stolons of mint cultivar Kosi was subjected to gamma irradiation (20 Gy and 40 Gy) and 42 promising putative mutants selected from both 20 Gy and 40 Gy of M₁V₁ generation based on growth and yield parameters were forwarded to M₁V₂, laid out in RCBD with two replications. The study revealed that essential oil yield exhibited significant positive association with leaf area, fresh herb yield, and shade dried herb yield. Hence, selection for these traits can improve yield. Path coefficient analysis revealed that shade dried herb yield per plant, leaf area, and plant spread exhibited positive direct effect on yield. Among these characters shade dried herb yield per plant and leaf area possessed both positive association and high direct effects. Hence, selection for this character could bring improvement in yield and yield components in menthol mint.