Arthropod community composition in agricultural landscapes is dependent on habitat characteristics, such as plant composition, landscape homogeneity and the presence of key resources, which are usually absent in monocultures. Manipulating agroecosystems through the insertion of in-field floral resources is a useful technique to reduce the deleterious effects of habitat simplification. Food web analysis can clarify how the community reacts to the presence of floral resources which favour ecosystem services such as biological control of pest species. Here, we reported quantitative and qualitative alterations in arthropod food web complexity due to the presence of floral resources from the Mexican marigold (Tagetes erecta L.) in a field scale lettuce community network. The presence of marigold flowers in the field successfully increased richness, body size, and the numerical and biomass abundance of natural enemies in the lettuce arthropod community, which affected the number of links, vulnerability, generality, omnivory rate and food chain length in the community, which are key factors for the stability of relationships between species. Our results reinforce the notion that diversification through insertion of floral resources may assist in preventing pest outbreaks in agroecosystems. This community approach to arthropod interactions in agricultural landscapes can be used in the future to predict the effect of different management practices in the food web to contribute with a more sustainable management of arthropod pest species.

Studies on the diversity of social wasps in agricultural environments represent an important step to identifying the ideal species to be used in biological pest control programs. There is a growing effort to acknowledge the diversity of such Hymenoptera in the state of Minas Gerais, but information on anthropized environments is still rare. The objective of this study was to obtain data on the diversity of social wasps in the Instituto Federal de Educação, Ciências e Tecnologia de Minas Gerais (IFMG), Bambuí campus, Minas Gerais, Brazil. Sampling was conducted from July 2012 to July 2014 with two methodologies: attractive traps and active search. This work confirms that a well diversified environment, even if anthropized, is rich in social wasp species. In addition, the great number of collected species, shows the importance of a long-term survey and the use of more than one method of collection. The high rate of collections of Polistes versicolor in a predominantly agricultural environment, coupled with other studies on this species as a predator of lepidopteran caterpillars, suggests the use of this species as a tool in the biological control of pests.

Kale (Brassica oleraceae var. acephala) is of great importance in human nutrition and local agricultural economies, but its growth is impaired by the attack of several insect pests. Social wasps prey on these pests, but few studies report the importance of this predation or the potential use of wasps as biological control for agricultural pests. This study aimed to survey the species of social wasps that forage in kale (B. oleraceae var. acephala), recording the influence of temperature and time of day on the foraging behavior of these wasps. The research was conducted at the Federal Institute of Education, Science and Technology of Minas Gerais - Bambuí Campus, from July to December 2015, when twelve collections of social wasps that foraged on a common area of kale cultivation were made, noting the temperature and time of collection for each wasp. Polybia ignobilis, Protonectarina sylveirae and Protopolybia sedula were the most common wasp species foraging in fields of kale. Interspecific interactions between wasp species did not affect their coexistence within kale fields, with peak foraging occurring between 1000 and 1100 hours. Social wasps are important predators of herbivorous insects in the agricultural environment and the coexistence of a great diversity of these predators can help control pest insects that occur in the crop. Moreover, knowing factors that influence foraging behaviors of common wasp species that occur in this crop is important for effective use of these insects in the biological control of pests.

Brazil stands out for its coffee plantations for which the 2015 harvest yielded a revenue of over 600 million dollars. Its production is closely related to biotic and abiotic factors, and insect pests are noted for reducing this production. However, those insects are highly influenced by biological control agents such as predator wasps. This study aimed to survey the wasps visiting intercropping coffee cultivation with different tree species. Four plots of coffee intercropped with different tree species and coffee in full sun (control) were sampled for comparison. Tree species were: Teak (Tectona grandis L.f), Australian redcedar (Toona ciliata M. Roem.), Mangium (Acacia mangium Willd.) and Avocado (Persea americana Mill.). Six hundred and thirty-nine individuals of social wasps were collected, with 20 species and 7 genera, and an overall diversity index of 1.14. The plot with Avocado had the highest Shannon diversity index (H ‘) 1.23 and the lowest dominance according to the Index Berger-Paker (DPB) 0.54.

Understanding the ecological and toxicological relationship between genetically modified cultivars (GM) and biological control agents is of great importance for discussions related to the compatability of GM cultivars and integrated management strategies for pest resistance. The present study evaluated the search behavior and predatory capacity of Orius insidiosus (Say) (Hemiptera: Anthocoridae) and Doru luteipes (Scudder) (Dermaptera: Forficulidae) on eggs and caterpillars of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) resistant or not to the protein Cry1F expressed in Bt corn. To determine the search time, a stopwatch was run until the capture of the first prey, predation capacity was evaluated by counting the prey remaining after 24 hours of infestation. The injuries of S. frugiperda in genetically modified and conventional corn in the presence and absence of predators was also evaluated. The predators were not able to distinguish between resistant and susceptible prey (eggs or caterpillars), given the predatory behaviour observed. There was no difference in searching time or predatory capacity between the predators for eggs and caterpillars of either resistant or susceptible S. frugiperda. In the presence of predators, the injury scores for resistant S. frugiperda on the Bt corn plants were lower. It was concluded that O. insidiosus and D. luteipes did not notice the presence of the protein Cry1F in the prey S. frugiperda, which may facilitate the combined use of GM corn and biological control in integrated management programs and for management of pest resistance.