Comprehensive Evaluation of Different Sugar Beet Varieties by Using Principal Component and Cluster Analyses

This study aimed to examine the main qualities and differences among sugar beet, fodder beet, and edible beet of fourteen genotypes from a collection obtained from an experimental farm (black soil) in Heilongjiang University and make a comprehensive evaluation for these varieties on the basis of six quality indicators. Fourteen genetic varieties of sugar beet roots were used as experimental materials, and the quality indicators were the total amino acid (TAA), betaine, sugar, potassium, sodium, and Alfa amino N (alpha-N) contents. Analysis of variance for the quality indicators showed significant differences among the genetic varieties. Principal component analysis (PCA) and cluster analysis (CA) were used to evaluate the variability in quality characteristic of the sugar beet roots and rank the contributions of the variables. According to PCA, the quality indicators of the fourteen genetic varieties were divided into four principal components with the cumulative variance contribution rate of 91.8%. The genetic varieties were again classified into four groups based on the CA method, which was in agreement with the results obtained using the PCA method. The results showed that multigerm genotypes including 'S204', 'Xintian 3-12', 'Shi Tian No. 1', and 'Y7792' were put in one group and had better qualities. The two methods were combined to establish a model to evaluate the qualities according to the comprehensive evaluation indicators. Therefore, combining the PCA and CA methods could be a feasible approach for the comprehensive quality evaluation of sugar beet genetic cultivars in China.