Correspondence and Path Analysis in Black Turmeric (Curcuma caesia Roxb.) Genotypes

Abstract

Curcuma caesia Roxb. is a critically endangered plant species. Studying the associations among traits and the direct and indirect contributions of various characters to fresh rhizome yield per plant is important for its genetic improvement. In the present study, 33 black turmeric genotypes were evaluated to estimate phenotypic and genotypic correlations and to assess the direct and indirect effects of yield related traits on fresh rhizome yield per plant. Phenotypic analysis revealed that vegetative traits exhibited non-significant, but positive associations with yield, indicating that plant vigour alone may not be reliable for selecting high-yielding genotypes. At the genotypic level, fresh rhizome yield per plant showed strong positive correlations with weight of the primary rhizome, cured rhizome yield per plant, weight of the mother rhizome, girth and length of primary and mother rhizomes, number of primary rhizomes, curing percentage and number of secondary fingers. Path coefficient analysis at both genotypic and phenotypic levels indicated that the weight of primary and mother rhizomes exerted the highest positive direct effects on fresh rhizome yield, suggesting their importance as key traits for yield improvement in Black Turmeric. These findings provide useful insights for formulating effective selection strategies aimed at enhancing rhizome yield.