Fig 1.
Principal component analysis (PCA) biplots based on hop leaf content among our wild hop samples (36 samples).
The variable contributions to the axes are shown in the gradient from red (low) to green (high).
Fig 2.
Heatmap of the metabolic content of hop leaves from the 36 wild hops according to the three clusters determined in the HAC.
A dendrogram was constructed using the “Manhattan” distance and “ward.D2” clustering method.
Table 1.
Quantification of hulupinic acid, xanthohumol, and bitter acids according to the three metabolic clusters. x represents the peak area found in the samples belonging to the cluster. The values (ng/ µ L) correspond to the concentration point of the tested range, adjusted according to the purity of each standard used.
Table 2.
Characteristics of the sixteen expressed sequence tag-simple sequence repeat (EST-SSR) loci used to assess the genetic diversity of the wild hop collection.
Fig 3.
Phylogenetic tree of 36 wild hops based on molecular data, calculated via the unweighted neighbor-joining method (based on Jaccard’s coefficient).
The samples are colored according to their metabolic cluster (cluster 1: red; cluster 2: green; or cluster 3: blue). The filled black circles indicate bootstrap values.
Fig 4.
Phylogenetic trees of 36 wild hops and worldwide hop varieties sampled to date, on the basis of molecular data, calculated via the unweighted neighbor-joining method (based on Jaccard’s coefficient).
The samples are colored according to their metabolic cluster (cluster 1: red; cluster 2: green; or cluster 3: blue), and the hop varieties worldwide are black. The filled black circles indicate bootstrap values.
Fig 5.
Phylogenetic trees of 36 wild hops, worldwide hop varieties and wild hops sampled to date, on the basis of molecular data, calculated via the unweighted neighbor–joining method (based on Jaccard’s coefficient).
The samples are colored according to their metabolic cluster (cluster 1: red; cluster 2: green; or cluster 3: blue), the worldwide hop varieties are in black, and the worldwide wild hops are in pink. The filled black circles indicate bootstrap values.
Fig 6.
Multivariate regression tree based on the 36 wild hops genetic and metabolic data.
The MRT is based on five groups. The colored vertical bar plots represent the mean quantity of the twelve metabolites at each node. The colored horizontal bar plots show the proportion of the metabolic cluster represented at each node, according to the colors in Fig 2. Allele presence is labeled “>=”, and all other alleles are labeled “<”. n represents the number of individuals contained in each node. The statistics at the bottom of the figure are the residual error, the cross-validated error, and the standard error.