Figure 4.

Comparative karyotyping of six diploid Solanum species. Chromosomes 1–12 from each species are arranged from left to right. Karyotypes of potato and tomato were developed from the same metaphase cells in Figure 2. Karyotypes of the remaining four species are developed from the same metaphase cells in Figure S4 in File S1. (a) Double arrows point to the two copies of tomato chromosome 4, which have a distinct arm ratio compared to chromosome 4 from other species. (b) Double arrows point to two closely linked red signals on S. etuberosum chromosome 2, the bottom red signal is predicted to be derived from the short arm of chromosome 7. For comparison, we used the karyotype of potato as our reference, see switches between red and green signals among these two species. (c) Arrow indicates the green signal on the short arm of S. etuberosum chromosome 7, which is predicted to be derived from the long arm of chromosome 2. (d) Arrow points to the green signal on the long arm of S. caripense chromosome 4, which is predicted to be derived from the short arm of chromosome 11. (e) Arrow points to the red signal on S. caripense chromosome 11, which is predicted to be derived from the long arm of chromosome 4. (f) Double arrows point to the two copies of eggplant chromosome 8, which have a distinctly large short arm compared to chromosome 8 from other species. (g) Arrow indicates the location of the red signal on the long arm of eggplant chromosome 10. This signal is located at the short arm of chromosome 10 from other species.