Genotype × environment interaction, rhizome yield stability and selection for region specific stable genotypes in turmeric (Curcuma longa L.)

The present investigation was carried out to determine the stability over years among seventeen genetic stocks of turmeric assembled from different places in India for high and stable rhizomes yield. The differences among genetic stocks, years and g × e interactions were highly significant for rhizome yield. The stable genetic stocks were selected on the basis of stability parameters, high mean, regression coefficient (bi) around unity and mean square deviations from regression (s2di) near zero. The environmental indices for rhizome yield also indicated clear effects over the year’s i.e. 1.85 in year I followed by 9.95 in years II; -6.31 in year III and -5.29 in the year IV. The largest AMMI1 gain of the grand mean occurs over years for picking stable genotypes/clones. Further partitioning of genotypes on the basis of AMMI and Eberhart and Russell, (1966) model, the clones/genotypes T-8, T-12 and T-13 were highly stable; T-11 and T-14 adapted to the average stable in low yielding environment/year and T-9 ant T-17 genotypes/clones with below average stable suitable for high yielding environment were recommended for commercialization.