Fig. 5
Selective sweeps in the Spinacia population. a The ratio of nucleotide diversity between wild S. tetrandra and cultivated S. oleracea (πSte/πSol) with 100-kb sliding window in 20-kb steps across the spinach YY genome. The blue solid line indicates the 1% cutoff outlier with significant selective sweep signals. b The ratio of nucleotide diversity between wild S. turkestanica and S. oleracea (πStu/πSol) in 100-kb sliding window in 20-kb steps. The blue solid line indicates the 1% cutoff outlier with significant selective sweep signals. c The composite likelihood ratio (CLR) with 20-kb grid size for the S. oleracea population. d A strong sweep signal at chromosome 3:106,112,216–108,343,948 bp harbors genes influencing several domesticated edibility traits including internode elongation and leaf area enlargement. e Expression (FPKM) of candidate genes for spinach domestication in internode tissue (top) and leaf tissue (bottom) compared between wild species (S. turkestanica: PI677111 and S. tetranda: PI677114) and cultivars (Sp75 and Cornell-9). f Comparison between cultivated S. oleracea (Sp75) and wild species (S. turkestanica PI677111 and S. tetranda: PI677114) phenotypes (f1, f6, f11), internode length (f2, f7, f12), internode cell length (f3, f8, f13), leaf size (f4, f9, f14), and leaf cell area (f5, f10, f15); comparison between cultivar (Sp75) and wild species for internode length measurement in cm (f16); internode cell length in μm (f17); internode cell area in μm2 (f18); leaf area in cm2 (f19); leaf cell length in μm (f20); and leaf cell area in μm2 (f21). Mean separation was performed using a t-test at P < 0.05. For wild species, average values of PI677111 and PI677114 were used for parameters in f16-f21 to draw comparison graphs