The role of integrating agroforestry and vegetable planting in structuring communities of herbivorous insects and their natural enemies in the Neotropical region

Abstract

The integration of agroforestry plots with ephemeral crops such as vegetables on the farm scale can probably serve as a refuge and source of beneficial insects. Therefore, agroforestry systems possibly represent an alternative that favors ecosystem services and help growers in the transition process from conventional to agro-ecological agriculture. This study aimed to understand the role of introducing agroforestry systems in structuring insect communities, with consequences for the abundance of herbivore and natural enemies, contributing to farm management and favoring biological control as an ecosystem service. Field surveys showed that agroforestry systems can harbor more species than horticultural crops, independent of the functional group. They also contain a greater diversity of herbivores and an even greater diversity profile of natural enemy communities. Agroforestry systems served as a source of natural enemies that can colonize horticultural crops when herbivores are present. As a consequence, natural enemies can establish a numerical response to herbivore abundance, but their communities are also affected by stochastic factors related to climatic conditions. Thus, agroforestry systems and agroecological practices might favor an agriculture based on the maintenance and conservation of ecosystem services.

Diversity and Spatial Distribution of Predacious Dolichopodidae (Insecta: Diptera) on Organic Vegetable Fields and Adjacent Habitats in Brazil

“…From previous studies, only unidentified species of Condylostylus Bigot have been reported from Neotropical agricultural systems (Togni et al 2010;Harterreiten-Souza et al 2014;Lundgren et al 2014). Harterreiten- Souza et al (2014) found that Condylostylus species are more abundant in areas with vegetable crops compared to agroforestry systems.…”

“…From previous studies, only unidentified species of Condylostylus Bigot have been reported from Neotropical agricultural systems (Togni et al 2010;Harterreiten-Souza et al 2014;Lundgren et al 2014). Harterreiten- Souza et al (2014) found that Condylostylus species are more abundant in areas with vegetable crops compared to agroforestry systems. Considering the dolichopodid diversity in Brazil, the adaptability to the environmental conditions of agricultural systems and the high abundance in field collections, studies on the diversity and structure of the dolichopodid assemblies may reveal important data for conservation and ensure availability of their ecosystem services.…”

Spatial Statistics and Age Structure of Leaf Cutting Ant Nests

“…Nests in Cerrado bring significant temporary resource for ants waiting for new colonisations in Eucalyptus areas, mainly in the case of neighboring areas. Under these conditions, the Cerrado can act as a refuge area for ants during the Eucalyptus harvest period, as previously verified for other insect species[19] [20]. Refuge areas have been intensely discussed in different con-the growing demand for younger trees, thanks to intense selection of clones[21].…”

Influence of Various Farmland Habitats on Abundance of Taeniaptera (Diptera: Micropezidae)

“…In a landscape context, the fallow, agroforestry systems, and native vegetation can be alternative places to mitigate these effects and act as secondary habitats or refugia, contributing to the permanence and maintenance of the species over time. For example, crops of banana (Musa [Musaceae]), sugarcane (Saccharum [Poaceae]), and cassava (Manihot [Euphorbiaceae]) are commonly used in agroforestry systems (for more details see Harterreiten-Souza et al 2014b) to diversify the product marketed by the farmer. After harvesting, the remains of these plants (trunks and foliage) are incorporated into the soil and can function as a breeding site that supports the development of Taeniaptera larvae (Fischer 1932;Cresson 1938;Silva et al 1968;Marshall 2010).…”