Morphological and biochemical characterization of onion (Allium cepa L.) germplasm by principal component analysis

Abstract

The present study was conducted to observe the variability source structure for 14 different morpho-biochemical characters towards yield in onion at the ‘C’ Block Farm of Bidhan Chandra Krishi Viswavidyalaya, Kalyani, Nadia, West Bengal, India during the winter (rabi) season of 2017-18 and 2018-19. The results revealed that the first four principal components exhibited eigen-value more than 1 and above with 71.53% cumulative variance. Traits viz., number of leaves at 60 DAT, equatorial diameter, the average weight of ten bulbs, number of scales per bulb, total sugar percentage, dry matter percentage, total soluble solids, vitamin C, phenol, pyruvic acid in PC1, days to maturity in PC2, plant height at 60 DAT in PC3, polar diameter in PC4 exhibited positive contribution towards yield. Different variables were loaded on the three principal component indicated that the traits number of leaves at 60 DAT, equatorial diameter, the average weight of ten bulbs, number of scales per bulb, total sugar percentage, vitamin C, phenol, pyruvic acid, dry matter percentage and total yield exhibited maximum proportion of the total variability. So, a breeder must put special emphasis on these traits while conducting selection in a hybridization programme of onion.