El aumento de temperatura puede favorecer la llegada de plagas de cultivos a los ecosistemas de alta montaña. Caracterización molecular y evaluación del efecto de la temperatura en el desarrollo de Mythimna unipuncta del Páramo Matarredonda
Thesis
Paramos are high mountain ecosystems distributed throughout the equatorial Andean region. These ecosystems are critical water sources for neighboring cities, crucial carbon reservoirs, and important centers of biodiversity. Despite their significance, they are currently threatened by factors such as climate change and the loss of native vegetation due to invasive species. Recent observations on the populations of the native species Paepalanthus columbiensis in the Matarredonda paramo in Colombia indicate that an unknown moth is heavily feeding on these plants. In this research, molecular barcoding (COI amplification) was used, and it was identified that the larval insects attacking these plants belong to the species Mythimna unipuncta (Lepidoptera: Noctuidae), which has previously been described as a worldwide crop pest with a great dispersal capacity that cannot survive temperatures below 15°C. Given its biology, it is likely that it is a pest whose dispersal patterns are affected by the increase in ambient temperature due to climate change. To further explore this possibility, a phylogeographic analysis of the mitochondrial COI gene of 36 species of the genus Mythimna was conducted, and the effect of temperature on larval development and survival rate was studied under three temperature treatments: 30°C day/20°C night, 25°C day/15°C night, and 20°C day/10°C night. It was found that the optimal developmental temperature for the species is 25°C day/15°C night, which is above to today’s Paramo´s temperature. Furthermore, we found that individuals from Matarredonda are genetically differentiated from individuals of the same species from other locations, which correspond to the recent expansion of a single haplotype possibly originating from North America which occurred approximately 44,000 years ago. These results may indicate that the arrival and dispersal of Mythimna in the paramo could be a consequence of the temperature increase caused by climate change. Further studies will be necessary to elucidate the impact of this pest on paramo vegetation and the ecosystem services they provide.
