Multivariate analysis and genetic diversity for tuber yield and quality traits in potato (Solanum tuberosum L.)

The present investigation was conducted to assess the genetic variability, stability and adaptability of potato genotypes across multiple environments for yield and quality improvement. A total of 357 genotypes including advanced breeding lines and released cultivars were evaluated during 2022-23 and 2023-24 at two locations using an augmented block design. Significant genotypic variation was observed for agro-morphological traits across environments, indicating substantial genetic variability. The phenotypic coefficient of variation was higher than genotypic coefficient of variation for most traits indicating influence of environment on trait expression. High heritability coupled with moderate to high genetic advance was observed for traits processing grade yield percent, dry matter, specific gravity, tuber shape, skin color, eye depth and flesh color indicating the predominance of additive gene effects. Strong positive phenotypic and genotypic correlation was observed for total tuber yield and marketable tuber yield, while dry matter content exhibited a negative association with yield traits. Path coefficient analysis revealed that marketable tuber yield had strong positive direct effect on total tuber yield. Cluster analysis grouped the genotypes into four major clusters, whereas principal component analysis explained 84.50% of the total cumulative variance through the first four components having eigen value greater than one. BLUP and AMMI stability analysis identified stable and high- performing genotypes across environments. Based on the combined performance across yield and quality traits, CP2390, CP3412, Kufri Sadabahar and CP2086 were identified as superior ideotype genotypes with potential for further advancement in potato breeding programme.