Comprehensive Evaluation of Main Agronomic Traits of 64 Chinese Kale Resources

As an important vegetable crop, the diversity of Chinese kale（Brassica oleracea var. alboglabra）germplasm resources is crucial for variety breeding and industrial development. The aim of this study was to systematically investigate six quantitative traits and 19 agronomic traits（including the six quantitative traits）of 64 Chinese kale germplasm resources, and comprehensively evaluate the germplasm resources by using methods such as difference analysis, correlation analysis, and principal component analysis. The results showed that: the variation coefficients of the six quantitative traits of the 64 Chinese kale germplasm resources ranged from 18.30% to 39.20%, and the order from large to small was petiole length ＞ plant height ＞ leaf length ＞ bolt diameter ＞ plant spread ＞ leaf width. Among them, the petiole length had the highest degree of variation, reaching 39.20%. There were high correlations among the traits. Plant height was extremely significantly positively correlated with plant spread（0.434**）and leaf length（0.369**）. Leaf width was significantly positively correlated with plant shape（0.291*）, leaf color was extremely significantly positively correlated with plant shape（0.411**）, and petiole length was extremely significantly positively correlated with leaf length（0.356**）. Principal component analysis showed that the cumulative variance contribution rate of the first seven principal components reached 71.879%, which were respectively related factors of morphological and maturity performance, related factors of appearance quality, related factors of plant shape and morphological characteristics of vegetative organs, degree of leaf shrinkage, anthocyanin in internodes, flower color, and degree of undulation at the leaf margin.