# Deciphering the Origins of Commercial Sweetpotato Genotypes Using International Genebank Data

## TL;DR

This study uses DNA and physical traits to identify sweetpotato varieties in Brazil, helping farmers legally register and sell their crops.

## Contribution

The study identifies key sweetpotato genotypes in Brazil using molecular and morphological data, supporting formal registration and commercialization.

## Key findings

- The 'Canadense' variety in Brazil matches the 'Blesbok' cultivar with high genetic similarity.
- Sergipe's 'white skin sweetpotato' does not match any known CIP accessions, suggesting regional uniqueness.
- The study supports formal registration of sweetpotato genotypes with Brazil's Ministry of Agriculture.

## Abstract

In Brazil, many sweetpotato varieties are grown under local names, making it hard to know exactly what type they are. Since sweetpotatoes are easy to grow from cuttings, different cultivars often become mixed up. This causes problems with selling them legally and tracking their origin. To help fix this, researchers studied 37 sweetpotato samples from four Brazilian states. They used DNA tools (called SSR markers) and looked at physical traits to compare them with sweetpotato varieties kept at the International Potato Center (CIP). The results showed that a popular variety known as “Canadense” in Brazil matched with less than a 0.05 Jaccard dissimilarity with the cultivar ‘Blesbok’. This finding can help growers and sellers officially register and market their sweetpotato crops. Another group of sweetpotatoes, called “white skin sweetpotato” from Sergipe, did not match any known accessions in the CIP collection. Overall, the study helps identify key sweetpotato types in Brazil, which will support their official registration with MAPA (the Ministry of Agriculture) and improve how sweetpotatoes are grown, sold, and used in breeding programs.

Sweetpotato genotypes, often known by regional names, are easily propagated via cuttings, which can lead to mixing and misidentification of cultivars. This complicates traceability and commercialization. Accurate characterization of common genotypes would support their formal registration and strengthen the sweetpotato value chain. Sweetpotato is a staple crop in Brazil, and in this study, four states, representing different geographic regions in Brazil, were selected. A total of 37 samples were collected in these states, and the samples were evaluated by SSR molecular markers and morphological traits. The samples were cleaned of virus and compared to the global sweetpotato collection held at the International Potato Center under the International Treaty on Plant Genetic Resources for Food and Agriculture. SSR markers effectively distinguished among accessions. The genotype locally known as “Canadense” matched closely both genetically and morphologically to the CIP accession ‘Blesbok’. This alignment paves the way for formalizing cuttings and root production of “Canadense”/‘Blesbok’ for commercial use. In contrast, several accessions marketed in Sergipe as “white skin sweetpotato” did not correspond to any known CIP accession, suggesting that they may be unique regional genotypes or acquired from other sources, since sweetpotato is an exotic crop in Brazil. Overall, the research identified key genotypes, supporting their official registration with Brazil’s Ministry of Agriculture, Livestock, and Supply, thereby enhancing the legal commercialization of cuttings and roots. Additionally, the clear molecular and trait-based classification will assist sweetpotato crop improvement programs in selecting appropriate parent lines for future crosses.