Genetic differentiation of Tecia solanivora from Colombia based on two mitochondrial genes: Cytochrome b and cytochrome oxydase I

Tecia solanivora (Povolny 1973) (Lepidoptera: Gelechiidae) represents the most important pest in potato (Solanum tuberosum) in Central, South America, and Spain. Most of studies made in this species have been focused on its pest management, but few have considered the evolutionary biology of this moth.  The present study was conducted to analyze the population genetics of the species by using larvae and adult samples obtained from Antioquia (North), Boyacá (Center), Norte de Santander (West) and Nariño (South) and two mitochondrial gene fragments: cytochrome b (Cytb) and cytochrome oxydase I (COI). The results obtained with both concatenated genes revealed that T. solanivora is genetically structured where Norte de Santander was the most differentiated population. This result might be explained because it was the first location of Colombia invaded by this insect. In addition, the genetic homogeneity found in the other regions of this country might be due to the movement of infested potato tubers from Cundinamarca and Boyacá (Center) to other Colombian locations. Tajima test results on gene neutrality showed that Norte de Santander is the only population of Colombia where T. solanivora is in expansion.  Finally, UPGMA tree constructed with Cytb sequences showed that Guatemala is the most differentiated population followed by Venezuela, Canary Islands, Colombia and Ecuador. This outcome coincides with the pattern of migration of this pest from Central to South America.