Genetic diversity assessment through principal component analysis in potato (Salamun tuberosun L.)

In order of importance for food production in comparison to 20 other major food crops, potato (Solanum tuberosum L.) ranks 4th in the world and 3rd in India. It produces high dry matter, minerals, vitamin C & B and carbohydrates per unit area. Besides its significance to human food security, potato is also a crop with fascinating genetic traits and cultural history (Swaminathan, 1999). For improvement in potato crop genetic diversity is required. However due to narrow genetic base in cultivated potato, in India lot of potential yet to be explore. Principal component analysis was done to estimate the variability in germplasm under study. For the principal component analysis each genotype was identified on the basis of correlation matrix as a single point in a standardized multidimensional space. The axes of this space were principal components obtained from the original data as orthogonal transformation of the original variety. In this way each principal component becomes a linear combination of the varietal scores corresponding to the original variables. The present investigation for assessment of genetic diversity in potato (Solanum tuberosum L.) ” was conducted at Vegetable Research Centre of the GB Pant University of Agriculture and Technology, Pantnagar, Uttarakhand during rabi season of 2007-08. The climate of this place is humid and subtropical and frost can be expected from last week of December to end of the January. Fifty potato genotypes and four checks were conducted in Augmented Block Design with 5 blocks. Each block contains 10 genotypes along with 4 checks and each plot contains 2 row of 2 meter long. Observations were recorded on 13 agronomical and quality traits to analyze the data by Principal Component Analysis through a software programme developed by IISR, New Delhi. Principal component analysis suggested by Hotelling (1933) after its original concep