Abstract: Variation, correlation analysis, cluster analysis and principal component analysis of primary agronomic traits of 41 vegetable soybean varieties that were planted around Huaihe River, including growth period, plant height, stem diameter, lodging, nodes on main stem, pod height, pods per plant, effective pods per plant, pod length, pod width, grains per pod and fresh weight of 100 grains were studied. The results showed that 12 agronomic traits of 41 vegetable soybean varieties had large variation, and the variation of pod height was the highest (variation coefficient was 31.41%), the least variation coefficient was 6.45% of pod width. Correlation analysis showed that, the correlation coefficients between growth period and plant height, pods per plant, pod length, as well as that between pod length and pod width were larger than 0.5, the absolute value of correlation coefficient between the other traits was less than 0.5. By cluster analysis, 41 species of vegetable soybean varieties were divided into four groups at 5.597 3 of the Euclidean distance, and the agronomic traits of each type were different. The principal component analysis showed that the total contribution rate of the seven agronomic traits that included growth period, plant height, stem diameter, lodging, nodes on main stem, pod height and pods of per plant was 87.028 1%, which could reflect the main agronomic traits of vegetable soybean.

Key words: vegetable soybean, agronomic traits, correlation analysis, cluster analysis, principal component analysis