Genetic analysis of Meloidogyne species in South Africa using the COI marker

New-generation molecular approaches and methods are currently being developed to accurately identify species and genetic diversity. Given the significant impact of Meloidogyne sp. on agriculture, understanding the genetic structure of its populations is essential. While DNA barcoding studies have been conducted in the family Heteroderidae, there has been a lack of research on haplotype diversity. Therefore, in 2024, a study was undertaken at the University of Limpopo to analyse haplotype diversity within the Meloidogyne genus based on the cytochrome c oxidase I (COI) region. In this study, a total of 73 sequences from South Africa were utilised (GenBank), representing four species (Meloidogyne sp., M. incognita, M. javanica, and M. enterolobii). The haplotype analysis revealed four haplotypes which displayed low nucleotide (π = 0.045) diversity. In contrast, haplotype diversity (Hd) was 0.49, and the number of segregating sites (S) was 23. The result showed that Meloidogyne sp had low variability in haplotype supported by the haplotype network. Tajima (D) and Fu's Fs were found to be positive (P < 0.05), whereas the overall FST value was 0.99 (P < 0.05). In conclusion, genetic analysis showed there was no high variation amongst papulation from South African populations.