Genetic parameters, association and genetic divergence study of the mutant (M4) population created through chemical and physical mutagenic agents for estimating selection criteria for essential oil yield in Pogostemon cablin Benth.

Pogostemon cablin, commonly known as Patchouli (family-Lamiaceae) is a perennial aromatic herb with many medicinal properties and has immense use in different pharmaceutical industries. In this study genetic variability and association studies were performed for 200 M 4 population derived from chemical and physical mutagenic agents. The trial was planted in Randomized Block Design and eleven morphological and quality characters were taken for the study during the year 2020. Analysis of variance (ANOVA) showed high phenotypic and genotypic coefficient of variation (PCV, GCV) for fresh herbage yield per plant, number of monopodia and number of sympodia. High heritability with high genetic advance was observed for the characters, like-length of sympodia (86.703, 28.942), plant height (86.001, 27.439). Correlation study revealed that length of sympodia has significant positive correlation with dry weight of herbage yield/plant, while essential oil yield percentage showed significant negative correlation with fresh herbage yield and dry herbage yield per plant. Patchouli alcohol percentage was also found to be significant and negatively correlated with fresh herbage yield and dry herbage yield per plant. Path coefficient study showed fresh herbage yield/plant to have highest positive direct effect (0.628) on dry weight of herbage yield/plant, while length of monopodia showed highest positive direct effect (0.120) on essential oil percentage. Genetic divergence study partitioned the genotypes into eight clusters, thereby showing great variability among them for the studied traits. So, for increasing essential oil quality characters like- number of sympodia and number of monopodia should be considered and for increasing herbage yield quality, length of sympodia should be taken as selection criteria. • Pogostemon cablin is an aromatic herb with medicinal and pharmaceutical importance. • Genetic parameters studied among mutated population. • Length of sympodia and plant height showed high heritability and genetic advance. • Herbage yield/plant showed maximum direct effect on dry herbage yield/plant. • Mahalanobis D2 study showed 8 clusters with high diversity among the studied genotypes. [ABSTRACT FROM AUTHOR]