Correlation and path analysis studies in ashwagandha [Withania somnifera (L.) Dunal]

Abstract

This study was aimed at probing into interrelationship among dry root yield per plant and some of its components by estimating their correlation and path coefficients. The result on phenotypic and genotypic correlation coefficient revealed that dry root yield was significantly and positively correlated with fresh root yield per plant (rp = 0.3343**, rg = 0.378**) and harvest index (rp = 0.732**, rg = 0.739**). However, days to flowering (rp = -0.203**, rg = -0.265**) and number of primary branch per plant (rp = -0.160*, rg = -0.252*) showed significantly and negatively correlated with dry root yield. Negative correlation of dry root yield both at genotypic and phenotypic level was seen with total alkaloid content in root (rg= -0.095, rp = -0.086). Path coefficient analysis revealed that most of the evaluated traits exhibited positive direct effects on dry root yield per plant was exhibited by harvest index (1.235) followed by dry plant weight per plant (0.647), days to 75 per cent maturity (0.134), number of secondary branches per plant (0.109), fresh plant weight per plant (0.102), leaf area index (0.038), plant height (0.016), root length (0.014) and total alkaloid content (0.006) these characters play a major role in recombination breeding and suggested that direct selection based on these traits will be rewarded for crop improvement of ashwagandha. But some characters which had negative and direct effect on dry root yield per plant followed by fresh root yield per plant, 100 seed weight, root diameter in collar region, number of primary branch per plant. The breeding methods such as selection would be effective for genetic improvement of these traits.