Partitioning G × E interactions through the GGE biplot method for root morphology in Ashwagandha [Withania somnifera (L.) Dunal]

A biplot analysis used in the present study, which delineated total variation into the three principal components (PCs), accounted for 96.69, 66.71, and 71.20% of the total GEI for root branches, diameter, and length, respectively. SKA-11 for root branching, SKA-17 and SKA-23 for root diameter, and SKA-23 and SKA-25 for root length were determined to be the most productive genotypes. Two mega-environments for root branches, diameter, and length have been identified using a GGE biplot. In the first mega-environment, the winning genotypes for root branches were SKA-29 and SKA-24, while in the second mega-environment, the winning genotype was SKA-11. SKA-19 and SKA-12 were the winning genotypes in the first and second mega-environments, respectively, based on root diameter. In terms of root length, the genotypes that were victorious in the first, second, third, and fourth mega-environments were SKA-26, AWS-1, SKA-3, and SKA-11. For root branches, Bhi16 was the most discriminating and representative environment; for root diameter, it was Bhi16; and for root length, it was Skn17, Jag17, Bhi17, Skn18, Jag18, and Bhi18. In order to enhance the morphology of Indian ginseng roots, it would be advised to breed for genotypes that are both widely adaptable and location-specific.