Figure 1.
Association between specimen age and PCR amplification success using primers ITS1F and ITS4.
Pearson Chi-square test of independence (N = 2763, d.f. = 2) significant at p<0.0001. Asterisks denote categories with standardized adjusted residuals significant at a Bonferroni-corrected α = 0.00833. See Table S2 for data and post hoc test results.
Figure 2.
Association between taxon (controlled for specimen age) and PCR amplification success using primers ITS1F and ITS4.
Pearson Chi-square test of independence: p<0.0001. Asterisks denote categories with standardized adjusted residuals significant α = 0.05. See Table S3 for data and post hoc test results.
Figure 3.
Assessment of concordance between taxonomic (herbarium determination) and DNA similarity assignment using nonmetric multidimensional scaling (NMDS) ordination of the pairwise genetic distance matrix.
a. Data symbols coded by genus. b. Data symbols coded by family.
Figure 4.
Classification potential of ITS mini-barcodes.
NMDS ordination of genetic distances based on ITS1 sequences, with symbols colored by genus. Table inset shows Pearson correlation coefficients between pairwise genetic distance matrices generated for the two spacer regions (ITS1 and ITS2) separately and the full-length sequences from the 1107-sequence dataset.
Table 1.
Improvement of PCR and sequencing success rates using ITS1 mini-barcodes.
Figure 5.
Plot of within- and between-species nucleotide divergence (bp).