Figure 5.

Hierarchical cluster analysis based on flower volatiles during blooming for nine cultivars (abbreviated names of cultivars are as in Table 1, and 1 to 3 represent different cluster groups; while U represents unopened; H: half opened and F: fully opened flower blooming stages). Group 1 represented the citron, group 2 comprised four subgroups (2A Ponkan, 2B sweet orange and Satsuma mandarin, and 2C Satsuma mandarin and Huyou, and 2D Yuhuanyou, Huyou and Qingjia), while group 3 represented pomelo and Huyou.