Fig. 1.

A clustering dendrogram based on the genetic distance of SNPs in 347 tobacco germplasm accessions. The distribution of the accessions to different 4 groups is indicated by the color code (group I: red, all the 255 flue-cured tobaccos including 121 domestic and 134 foreign accessions, respectively; group II: blue, all the 5 Nicotiana rustica L. accessions; group III: pink, all the 37 wild tobacco accessions; and group IV: black, the left 50 accessions including 3 maryland tobaccos (red solid circle), 6 oriental tobaccos (blue solid circle), 4 cigar tobaccos (pink solid circle), 6 burley tobaccos (black solid circle), and 31 sun-cured tobaccos).