Ecological infrastructure associated with vegetable production systems and its role in natural biological control of pests

In recent decades, concern has increased about the deterioration of ecosystem functions associated with biodiversity loss in simplified agricultural landscapes. In this context, promoting functional biodiversity and managing ecological infrastructure are considered relevant strategies to enhance biological pest control. However, their role in vegetable production systems has been less studied in the region. The objective of this study was to analyze plant diversity and associated arthropod fauna in and around tomato greenhouses, and their potential relationship with natural pest control. To this end, two vegetable production farms in southern Uruguay were studied, one under organic management and the other under integrated pest management. At each farm, a tomato growing cycle was characterized between November 2020 and June 2021, including the main weeds within the crop and the surrounding spontaneous vegetation of the greenhouses. Arthropods were sampled using yellow sticky traps, sweep netting, plant collection, and direct observation, and were classified into functional groups. In addition, the main crop pests, Trialeurodes vaporariorum and Phthorimaea absoluta, were monitored. The results showed differences in arthropod community composition between farms. The farm under integrated management had a higher total abundance of arthropods, whereas the organic farm showed a higher relative abundance of natural enemies and a more favorable pest: natural enemy ratio. Moreover, pest populations reached lower abundance levels in the organic farm and exhibited temporal dynamics more closely aligned with the presence of natural enemies. Within the greenhouses, the main weed species hosted distinct arthropod communities depending on farm management. In the surrounding areas, the edges of the organic farm had higher plant richness and cover, and a more complex structure, which were associated with greater predator abundance and higher arthropod diversity. Overall, the results suggest that vegetation associated with horticultural crops influences arthropod community composition and their potential for biological control.