Impact of pesticides on the arthropofauna associated with potato (Solanum tuberosum) cultivation in Cusco-Peru

Abstract

The impact of several pesticides on the diversity of arthropofauna associated with commercial potato cultivation was evaluated in Mollepata, province of Anta in Cusco-Peru, to determine which trophic guilds (TG) are affected. The treatments were fipronil, propineb and conventional (rotation of several pesticides). Thirty-five pitfall traps were placed in each treatment with the purpose of collecting the arthropofauna in potatoes. Five applications of the corresponding treatment were carried out and a total of five check-ups were carried out with a frequency of fourteen days. The most abundant families were Hemiptera: Cicadellidae (19.82%), Coleoptera: Chrysomelidae (16.33%) and Diptera: Sciaridae (11.92%). Propineb was the treatment that presented, at the family level, the largest total number of individuals. For the entire study, at the level of TG, the decreasing sequence of the total number of families was: phytophagous with 30 families (32.97%); predators 23 families (26.37%); detritivores 20 families (21.98%); parasitoids 10 families (9.89%); pollinators six families (6.59%) and finally omnivorous with two families (2.20%). Propineb presented the highest values of the total number of individuals in phytophages and parasitoids. On the other hand, alpha diversity indices did not present differences between treatments for omnivores, detritivores, pollinators and predators. The beta diversity indices were variable, generally obtaining greater similarity between the fipronil and conventional treatment. The phytophagous and parasitoid TGs were those that presented the most differentiated values when evaluating the effect of pesticides on soil arthropofauna based on alpha diversity indices.