Fig 1.
(a): Map of northeast China showing the distributions of chloroplast haplotypes (A~Y). (b): Median-joining network for 25 chloroplast SSR haplotypes and 124 individuals in Chinese wild Ussurian pears (Table 3). The haplotypes are indicated by circles and the colors correspond with the color of the haplotypes in Fig 1 (a), and small red circles show median vectors. The size of each pie chart is proportional to the frequency of corresponding haplotype. (1)-1 including 2 haplotypes was detected mostly in the north east of Heilongjiang, and (1)-2, (1)-3, and (1)-4 contained the haplotypes found in Jilin, Inner Mongolia, and Mudanzhang City, Heilongjiang, respectively. Most of the median vectors were included in (2).
Table 1.
Distribution of 13 wild populations of P. ussuriensis Maxim.
Table 2.
Genetic diversity within a population for 20 nSSR markers.
Table 3.
Number and distribution of haplotype within 13 wild populations of P. ussuriensis Maxim.
Fig 2.
(a) The result of STRUCTURE using all samples. Average log-likelihood values over 10 runs ± SD, from 1 to 20 with all samples. (b) The result of STRUCTURE using only wild Ussrian pears in China. Average log-likelihood values over 10 runs ± SD, from 1 to 10.
Fig 3.
(a) Percentages of membership of genotypes to clusters (q value) inferred at K = 5 applying only wild Ussurian pears in China to STRUCTURE analysis. (b) Geographical distribution of wild populations originating from Inner Mongolia, Heilongjiang and Jilin province. Pie charts represent the proportion of gene pools based on STRUCTURE analysis when only wild Ussurian pears were applied to the analysis (K = 5).
Fig 4.
Percentages of membership of genotypes to clusters (q value) inferred at K = 10 applying all samples including wild and cultivated pears to STRUCTURE analysis.
Each genotype is represented by vertical line divided into colored segments. The length of the vertical lines indicates the proportions of genome attributed to the inferred clusters. * means cultivated pears.
Fig 5.
Unrooted neighbor-joining tree based on Nei’s DA distance value among populations.
The number on points of divergence represents bootstrap values. (1) The 6 populations (IMQS, IMTHL, IMPJG, IMRSL, IMLMD, and IMSLG) originating from Inner Mongolia. (2) The 5 populations (HLYCS3, HLFYX, HLSWX, HLYCS2, and HLYCS1) from Heilongjiang. (3) HLMTZ from Mudanjiang, Heilongjiang. (4) The cultivated Ussurian pears. QZL1 and QZL2 were combined. (5) P. pyrifolia, P. bretchneideri, P. sinkiangensis, and P. communis. (6) Japanese cultivated pears (P. pyrifolia) and wild Ussurian pear from Japan (Iwateyamanashi).
Fig 6.
Discriminant analysis for canonical 1 and 2.
(Ⅰ) represented flower morphologies measured from 9 wild populations; Inner Mongolia (1:IMQS, 2: IMTHL, 3:IMPJG, 4:IMLMD, and 5:IMSLG), Heilongjiang (7:HLYCS, 6:HLFYX, and 9:HLMTZ), and 26 Ussurian pear cultivars (8). (Ⅱ) represented fruit morphologies, containing 5 wild populations; Inner Mongolia (1:IMQS, 2:IMTHL, 3:IMPJG, and 4:IMSLG), Heilongjiang (5:HLYCS), and an Ussurian pear cultivar ‘Nanguoli’(6).