Diversidade e estrutura genética em população de melhoramento de solanum tuberosum l.

Abstract

The potato (Solanum tuberosum L.) is one of the most economically important crops in Brazil. Brazilian potato farming still relies mainly on cultivars developed in other countries. These temperate climate cultivars may show poor adaptation to Brazilian edaphoclimatic conditions. Therefore, there is a need for more adapted and modern cultivars that can meet Brazil's tropical edaphoclimatic and technological conditions. The broad genetic diversity of plants can serve as a source of desirable alleles, providing not only the possibility of gains with selection but also adaptation to environmental changes. Knowledge about the level of diversity and genetic structuring can rationalize breeding strategies. Based on this scenario, the study aimed to characterize the diversity and genetic structuring in potato clones from the UFLA Breeding Program. Five SSR markers were used to differentiate 111 Solanum tuberosum clones. The primers resulted in 15 polymorphic alleles, with an average of 3 alleles per locus. The complement of the Jaccard distance matrix was represented by a dendrogram via UPGMA clustering. Additionally, the distances between the potato clones were also visualized in a scatter plot with the first two principal components. The expected heterozygosity (He) and the polymorphic information content (PIC) were 0.346. The results suggest a relatively low genetic diversity among the analyzed potato clones and indicate that the germplasm is not structured into distinct groups. Despite this lower diversity compared to other studies, there is still sufficient diversity for several breeding cycles. It is suggested to expand the genetic base over the years by introducing new genetic resources, such as the exchange of germplasm with other institutions and breeding programs, to avoid possible limitations in genetic improvement and ensure the future sustainability and productivity of potato crops.