Multivariate analysis for evaluation and classification of toria germplasm accessions

Abstract

Multivariate analysis was carried out with 22 agro-morphological traits in 92 germplasm accessions of toria [Brassica rapa (L.) var. toria]. Principal factor analysis identified eight principal components which explained about 62% variability. PC 1 had 15.04% of total variation in agro-morphological traits; PC 2 depicted 8.55% of total morphological variability, while PC 3 accounted for 7.68% of the total variation. Varimax rotation enabled loading of similar type of variables on a common principal factor permitting to designate them as seed yield, maturity, leaf and siliqua characters and oil content factors. The germplasm accessions TC 5, TC 36, TC 59, TC 86 and TC 87 were found to be superior on the basis of principal factor scores with regard to seed yield, its main components and oil content when both the principal factors were considered together. These accessions may further be utilized in breeding programmes for evolving toria varieties/populations with high seed yield and superior oil content. Hierarchical cluster analysis categorized all the 92 accessions into 10 clusters containing one to 35 accessions. Based on the inter-cluster distances, maximum genetic diversity was observed between C VIII and C X (87.16) followed by C VI and C X (86.22), C VII and C X (85.84) and C III and C VII (84.57) indicating that germplasm accessions from these clusters can usefully be hybridized for getting superior recombinants in segregating generations. The results of cluster and principal factor analyses were in corroboration.