Table 1.
Characteristics of 20 melon varieties used for developing the melon DNA fingerprinting core SSRs.
Figure 1.
Application of the core set of SSR primers and the expression of melon DNA fingerprinting QR Code.
a. SSR primer MU4628-1 could distinguish the thin rind melon and the thick rind melon. In this study, the total number of SSR primer pairs which could distinguish thin rind melon and thick rind melon clearly was 52. b. Each pair of the core SSR primers could be used in seed purity tests. In this example, fingerprinting codes of MR-1 and Topmark were analyzed. We found that SSR E (SSR12083, labeled by a red frame) had the bigger amplicon length difference in the two parents, so we chose SSR12083 to identify F1 seed purity. Most of the F1 were parent hybrid types, while few of them were female parent type (labeled by a blue frame). c. The DNA fingerprinting QR code of melon line 3-2-2 is at the left. This picture could be scanned by computers or a mobile device, such as a smartphone, PDA and so on. The right side shows the translation result of the left picture after scanning.
Table 2.
The 18 core SSRs for DNA fingerprinting.
Figure 2.
UPGMA dendrogram of 471 melon accessions based on the 18 core set of SSR markers.
Materials with the same fingerprinting codes had been merged. The end of each branch represents a melon variety, and many names of varieties had been omitted due to space considerations. For more detailed classification information, see Figure S1. The 471 test accessions were in 3 distinct clusters: color codes red, blue, and pink.
Figure 3.
Alignment of homonym melon varieties and genetic purity detection of commercial melon varieties. a.
Alignment of 4 groups of homonym melon varieties. Qitian No.1, Qitian No.2, Zetian No.1 and Fengtian No.3 represent four commercial varieties in which homonym phenomena were found. Numbers to the left of colons are the numbers of varieties in Table S2; fingerprinting codes are listed to the right of the colons. b. Genetic purity detection results of commercial melon varieties. CV: commercial cultivar; CVH: commercial cultivar labeled “hybrid” or “F1”; CV (thin): commercial thin rind melon cultivar; CVH (thin): commercial thin rind melon cultivar labeled “hybrid” or “F1”; CV (thick): commercial thick rind melon cultivar; CVH (thick): commercial thick rind melon cultivar labeled “hybrid” or “F1”.
Table 3.
Materials with the same fingerprinting codes.