Nuclear and chloroplast DNA differentiation in Andean potatoes

Abstract

Over 3500 accessions of Andean landraces have been known in potato, classified into 7 cultivated species ranging from 2x to 5x (Hawkes 1990). Chloroplast DNA (ctDNA), distinguished into T, W, C, S, and A types, showed extensive overlaps in their frequencies among cultivated species and between cultivated and putative ancestral wild species. In this study, 76 accessions of cultivated and 19 accessions of wild species were evaluated for ctDNA types and examined by ctDNA high-resolution markers (ctDNA microsatellites and H3 marker) and nuclear DNA restriction fragment length polymorphisms (RFLPs). ctDNA high-resolution markers identified 25 different ctDNA haplotypes. The S- and A-type ctDNAs were discriminated as unique haplotypes from 12 haplotypes having C-type ctDNA and T-type ctDNA from 10 haplotypes having W-type ctDNA. Differences among ctDNA types were strongly correlated with those of ctDNA high-resolution markers (r = 0.822). Differentiation between W-type ctDNA and C-, S-, and A-type ctDNAs was supported by nDNA RFLPs in most species except for those of recent or immediate hybrid origin. However, differentiation among C-, S-, and A-type ctDNAs was not clearly supported by nDNA RFLPs, suggesting that frequent genetic exchange occurred among them and (or) they shared the same gene pool owing to common ancestry.

Comparative differentiation in mitochondrial and chloroplast DNA among cultivated potatoes and closely related wild species

“…and S. stoloniferum were evaluated (Table 2). Their banding patterns of ctDNA using RFLP analysis (Hosaka, 1986), seven SSR and one cleaved amplified polymorphic sequence (CAPS) markers (Sukhotu et al, 2004) were all obtained previously in Sukhotu and Hosaka (2006). To disclose mtDNA polymorphisms, various types of DNA markers including three SSR markers described above were used.…”

Análisis de la variabilidad en poblaciones naturales de Solanum, secciones Lycopersicon y Basarthrum.

“…This situation could be explained by a recent origin of these wild species. A similar complex situation has been found in the wild relatives of other domesticated species in the Solanaceae (Sukhotu et al, 2004). Given all of this, we can conclude that it is the species in series Caripensia that are the closest wild relatives (given the S. muricatum haplotypes muricatum 1a, 1b, 1c, 3a, and 3b and typical haplotypes of the series Caripensia all grouped together, supported by an 86% boostrap value).…”

“…The origin of most domesticates turns out to be more complicated than supposed at first analysis and may involve different scenarios, such as polyphyletic origins and the existence of complex interrelationships among the wild relatives and the domesticate Sukhotu et al, 2004). The evolutionary history of the pepino is no exception.…”

Molecular Studies on the Origin of the Cultivated Potato: A Review

“…andigena possess the T type. Sukhotu et al (2004) presented results combining chloroplast haplotypes with nuclear DNA restriction fragment length polymorphisms (RFLP). The results showed that nuclear DNA RFLPs only supported the differentiation between the chloroplast haplotypes of the W type on one hand and the C, S, and A types on the other hand.…”

“…Differentiation of the chloroplast DNA could have occurred in the 'ancestral species' complex from which several wild species, as well as cultivated species, evolved. Sukhotu et al (2004) also claimed that the fact that many different haplotypes are found in wild species and in cultivated material suggested successive domestication events and parallel differentiation of wild species from the ancestral species complex.…”