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Agriculture represents one of the major strengths of the economic sector in Brazil. The need to avoid economic losses because of insect pest populations is one of the greatest challenges faced by this sector. Insect pests have caused annual losses of US$12.0 billion to the Brazilian economy, of which approximately US$1.6 billion are because of exotic pest species. Furthermore, exotic insect species often show greater potential to cause harm than native species. In Brazil, since the late nineteenth century, 24 species of insect pests have been introduced into the country, and they have caused significant economic losses. Many of these species, including Bemisia tabaci, Hypothenemus hampei, Ceratitis capitata, Oryzophagus oryzae and Anthonomus grandis, are major crop pests, and they were accidentally introduced during trading of agricultural products. In this review, we present an overview of Brazilian agriculture, a brief history of the introduction of insect pests in the country and the Brazilian legislation on agricultural defence, and we estimate the economic losses caused to the Brazilian economy by the main insect pest species that have been introduced into Brazil over the last 112 years.

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Population dynamic of Benisua tabaci B biotype in monoculture tomato crop and consortium with coriander in organic and conventional crop system Due to its high genotypic plasticity, the control of the silverleaf whitefly Bemisia tabaci B biotype (Hemiptera: Aleyrodidae), is difficult. This insect may cause severe damage to the tomato crop as a vector of several viruses. The management of the production system and the consortium with other crops may have a direct effect on this herbivore population, without the need of chemical insecticide spraying. The effect of organic and conventional production systems and the tomato-coriander consortium were evaluated in this study, in field, during May-September 2006. Adults of whitefly and its natural enemies were monitored using yellow adhesive traps installed at the edge and inside the experimental plots, and nymphs were sampled by direct observation on tomato plants. Although adult populations in the neighborhood of the different treatments were equivalent, the abundance of whitefly adults was significantly lower in the plots with the consortium tomato-coriander in both systems, conventional and organic. Significant reduction in the amount of nymphs per plant was only observed in the consortium tomato-coriander when all treatments were compared. There were more natural enemies in organic system and a negative correlation was observed between natural enemies abundance collected in the traps and whitefly nymphs' density. The association tomato-coriander and the organic management of the agroecossystem favored natural biological control of B. tabaci.

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Phyllophaga capillata (Blanchard) is the most important soil pest in soybean crops in Central Brazil (Federal District and Goiás state). The objective of this work was to study the bio-ecology of P. capillata in the field in the Cerrado of Central Brazil, relating its biology and behaviour to the climatic characteristics of this biome. The study was conducted over three years in a soybean [Glycine max (L.) Merr.] production area (≈6000 ha) in the Federal District. Field samplings were taken to observe the biological stages of P. capillata, preferred oviposition sites and the adult swarming period. Phyllophaga capillata presented an univoltine cycle that lasted about 10 months of egg to inactive adults, and 12 months until the appearance of active adults. Eggs were found in the field in October and November. The larval stage occurred between November and June. Pre-pupae were observed in June and the pupae between July and August. Inactive adults were observed in August and September, and the swarming period was between September and December. Females preferred to oviposit in sites with taller plants. This species synchronises its active phases (larvae and active adults) with soybean cultivation and the rainy season (October/ March) in the Brazilian Cerrado. Alternatives for pest management based on their bio-ecological characteristics are presented.

1. Changes in land use have been identified as one of the main drivers of global biodiversity loss, and also negatively affect ecosystem services. Dung beetles are capable of providing a variety of ecosystem services and can be used as bioindicators.2. We assess whether the land use changes of the Cerrado areas for agricultural purposes (pasture and soybean crops) affects dung beetle community and the associated ecosystem services (dung removal and secondary seed dispersal) provided by dung beetles on their diversity in the Federal District, Brazil.3. A total of 32 261 individuals (Scarabaeinae, Aphodiinae and Anaidinae) were collected. The abundance and biomass of dung beetles were significantly higher in soybean (n = 19 354; biomass = 1145.4 g) and pasture (n = 9865; biomass = 753.6 g) compared to cerrado (n = 3042; biomass = 311.6 g). Sixty-one species were collected in the cerrado, 58 in soybean and 56 in pasture, most species were paracoprids (52-60%), but no significant differences were observed for the species richness and diversity indices among the different land use systems. The structure of the dung beetle community in areas of the cerrado was distinct from that in pasture and soybean areas, and the latter two were similar. The land use systems did not affect the ecosystem services provided by dung beetles.4. Our results showed that the Cerrado dung beetle community was unique and specific, indicating an imperative need for its preservation, due to its intrinsic value and its importance for the functioning of the ecosystem.