SYSTEMATICS, GENETIC DIVERSITY ASSESSMENT, AND ACQUISITION OF POTATOES, CARROTS, AND THEIR RELATED WILD RELATIVES
Location: Vegetable Crops Research Unit
Title: Genetic diversity and origin of cultivated potatoes using plastid microsatellites
| Gavrileno, Tatjana - |
| Antonova, Olga - |
| Shuvalova, Anna - |
| Krylova, Ekaterina - |
| Alpatyeva, Natalia - |
| Rogozina, Elena - |
| Novikova, Lubov - |
Submitted to: Genetic Resources and Crop Evolution
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 28, 2013
Publication Date: N/A
Interpretive Summary: Wild and cultivated potatoes have been the subject of intensive study of what constitutes a species and how these species are interrelated to each other. This study examined, with DNA markers from the chloroplast (inherited from the mother plant only) 392 collections of cultivated and wild potato species from the Russian National potato collection and the US germplasm collection that were recently examined with DNA from the nucleus that is inherited from both parents. These collections included 237 from cultivated potatoes and 155 from wild potatoes. The study showed that the diversity of chloroplast DNA was highest in the Central Andes, lower in northern Andes (Ecuador, Columbia) and significantly lower in Chile and the southern Andes. The results from chloroplast DNA are in general in agreement with prior results from nuclear DNA. Plastid DNA data are very useful to reveal origins of the hybrid cultivated potato species Solanum juzepczukii and Solanum curtilobum, supporting the wild potato species Solanum acaule to be, in most cases, the mother donor. Chloroplast DNA also shows greatly reduced genetic diversity in cultivated species in comparison with wild species, dramatically highlighting decreasing in levels of genetic diversity through domestication. These results are very useful for potato breeders in that it informs them of the genetic constitution of these wild species that helps them better plan their breeding programs.
We examined, with 15 plastid microsatellite loci and with the 241 bp deletion marker characteristic of Chilean S. tuberosum, 392 accessions of cultivated and wild potato species, mostly from the experimental subset of the Russian National potato collection, recently characterized by nuclear microsatellites and morphology, but also including some accessions from the US potato gene bank and from the International Potato Center. These included 237 accessions of all seven cultivated species recognized by Hawkes in 1990 and 155 accessions of 21 wild species close relatives, and Solanum outgroups. Ninety-three alleles were detected in the microsatellite loci, providing 127 haplotypes for all 392 accessions. Twenty-eight of these haplotypes consist of more than one accession per haplotype. Haplotype diversity in cultivated potatoes was highest in Central Andes, lower in northern Andes (Ecuador, Columbia) and significantly lower in Chile and the southern Andes. Neighbor joining results of plastid SSRs are in general in agreement with prior hypothesis and data from nuclear DNA. Plastid DNA markers are very useful to reveal origins of the hybrid cultivated potato species Solanum juzepczukii and Solanum curtilobum, showing maternal and paternal ancestors, with S. acaule supported as the maternal donor in most cases. There was very restricted chloroplast genetic diversity in cultivated species in comparison with wild species. A total of 206 of 237 (88.2%) of the cultivated accessions shared four most frequent haplotypes. There was much greater diversity in the 155 wild species accessions, which consisted of 110 haplotypes, dramatically highlighting decreasing in levels of genetic diversity through domestication.