Composición y fluctuación poblacional de la araneofauna en el algodonero de la Universidad Nacional Agraria La Molina, Lima, Perú / Composition and population fluctuation of the spider community in a cotton field at Universidad Nacional Agraria La Molina, Lima, Peru

En el presente trabajo, se evaluó la araneofauna durante todo el periodo fenológico del cultivo de algodón, utilizando dos técnicas de muestreo (búsqueda directa y trampas de caída). Se registraron 2304 individuos, agrupados en 50 especies y 18 familias. Las arañas estuvieron presentes durante todo el periodo del cultivo, relacionándose positivamente a su desarrollo fenológico, y donde las prácticas agronómicas, la temperatura y humedad no fueron influyentes en su abundancia, excepto por la cosecha, actividad que sí influenció negativamente sus poblaciones.

In this work, the spider community was assessed during the whole phenological period of a cotton crop using two sampling techniques (direct search and pitfall traps). 2304 individuals were registered, grouped into 50 species and 18 families. The spiders were present during the whole crop’s period; positively related to its phenological development; agronomic practices, temperature and humidity were not influential in their abundance, except for harvest, which negatively influenced their population.

Correction: Fall armyworm migration across the Lesser Antilles and the potential for genetic exchanges between North and South American populations.

[This corrects the article DOI: 10.1371/journal.pone.0171743.].

Fall armyworm migration across the Lesser Antilles and the potential for genetic exchanges between North and South American populations.

The fall armyworm, Spodoptera frugiperda (J. E. Smith)(Lepidoptera: Noctuidae), is an important agricultural pest of the Western Hemisphere noted for its broad host range, long distance flight capabilities, and a propensity to develop resistance to pesticides that includes a subset of those used in genetically modified corn varieties. These characteristics exacerbate the threat fall armyworm poses to agriculture, with the potential that a resistance trait arising in one geographical location could rapidly disseminate throughout the hemisphere. A region of particular concern is the Caribbean, where a line of islands that extends from Florida to Venezuela provides a potential migratory pathway between populations from North and South America that could allow for consistent and substantial genetic interactions. In this study, surveys of populations from Peru, Bolivia, Paraguay, and Trinidad & Tobago expand on previous work in South America that indicates a generally homogeneous population with respect to haplotype markers. This population differs from that found in most of the Lesser Antilles where a combination of genetic and meteorological observations is described that indicate fall armyworm migration from Puerto Rico to as far south as Barbados, but does not support significant incursion into Trinidad & Tobago and South America. Air transport projections demonstrate that the wind patterns in the Caribbean region are not conducive to consistent flight along the north-south orientation of the Lesser Antilles, supporting the conclusion that such migration is minor and sporadic, providing few opportunities for genetic exchanges. The implications of these findings on the dissemination of deleterious traits between the two Western Hemisphere continents are discussed.