Cytochrome b Gene of <i>Globodera pallida</i> Populations from Colombia Reveals Diversity Within Populations

Potato cyst nematodes (PCNs) <i>Globodera rostochiensis</i> (golden PCN) and <i>G. pallida</i> (pale PCN) are major pests responsible for significant yield losses in <i>Solanum tuberosum</i> crops. Our study incorporates new mitochondrial Cytb sequences from Colombian PCN populations and analyzes a total of 193 <i>Globodera</i> spp. sequences from all continents, except Antarctica. Phylogenetic analysis using approximate Bayesian computation revealed two main clades: (i) a monophyletic group comprising populations from Colombia, Costa Rica, Panama, and Peru and (ii) a second clade with populations from North America, Africa, Europe, Asia, and New Zealand, showing 100% bootstrap support. Genetic structure analysis identified two geographically distinct groups, with Colombian populations forming one group, distinct from other populations, indicating substantial genetic divergence. The Cytb marker also revealed significant haplotype diversity within the Colombian populations, with no matching haplotypes found in Europe, Asia, or North America. Only one haplotype was shared with southern Latin American populations. These findings provide important insights into the genetic diversity and geographic distribution of PCNs, and future research will be crucial in tracing the evolutionary history and further clarifying the potential pathways of introduction ad spread in Latin America.