Fig. 4

Summary of comparison information among primary, core and whole sets. A The NJ tree and genetic diversity of whole set, primary and core sets. Pi nucleotide diversity, MAF minor allele frequency, AGD average genetic distance, GDR genetic distance range. CI cluster I, CII cluster II, CIII cluster III, CIV cluster IV, CV cluster V, CVI cluster VI, CVII cluster VII. The different letters indicate a significant difference in p = 0.05 levels by the T-test; B Frequency distribution histogram of pairwise genetic distance of 253 accessions. C The histogram of the numbers of accessions of whole, primary and core sets in seven groups according to NJ tree. D The histogram of the numbers of accessions of whole set, primary set and core set in cultivated statuses (ML modern landraces, AL ancient landraces), two basins (PR the Pearl River Basin, YR Yangtze River Basin) and seven water systems (WS01 Liujiang River System, WS02 Hongshui River System, WS03 Beipanjiang River System, WS04 Nanpanjiang River System, WS05 Yuanjiang River System, WS06 Wujiang River System, WS07 Chishui River System; PR Pearl River Basin, YR Yangtze River Basin)