Insights from genetic research: SNP analyses confirm white clover naturalization in Brazil

White clover (Trifolium repens) is a stoloniferous legume herb native to Eurasia which has been introduced and spread globally. In Brazil, it was introduced as a forage crop. While previous research focused mainly on agricultural benefits of the species, much remains unclear about its colonization dynamics, introduction process and potential threats in the Brazilian territory. This study aims to estimate the genetic diversity of white clover populations in Brazil and assess the influence of cultivars on these populations’ diversity. Through MIG-Seq analysis, 1097 single nucleotide polymorphisms (SNPs) showed that Brazilian populations have 94% within-population variation. Populations from two mountainous areas clustered together, while those of rural and urban areas formed a second cluster. Cultivars were less diverse; 27% of their genetic variability was found between cultivars. We observed the admixture of some populations with cultivars, while more isolated mountainous populations were singular in their genetic background. We can conclude that several Brazilian populations possibly descended from native Eurasian populations brought during European immigration. Other populations appeared to share ancestry with cultivars, indicating possible biological escapes of cultivars, forming these naturalized populations. Considering previous knowledge on the species distribution and our present genetic findings, white clover can be confirmed as naturalized in Brazil.