Pest management of stink bugs (Hemiptera: Pentatomidae) in soybean [Glycine max (L.) Merr.], corn (Zea mays L.) and cotton (Gossypium spp.) agroecosystems has become a major concern in several countries of the Americas. In this review, we report an overview on geographical distribution, injury, damage and methods used to control (plant resistance mechanisms, biological control) the most important stink bugs in the Americas, with an emphasis on Brazil, the implications of the trend towards decreased susceptibility of stink bug populations to insecticides and the current difficulties of the management of these insect pests. Currently, the Neotropical brown stink bug Euschistus heros (Fabricius) is less susceptible to organophosphate insecticides than in the past. A slight reduction in E. heros susceptibility to pyrethroids and, to a lesser extent, to neonicotinoids has also been observed. In addition, the green‐belly stink bug [Dichelops melacanthus (Dallas)] is more tolerant to the three classes of insecticides (neonicotinoids, organophosphates and pyrethroids) than E. heros. Metabolic detoxification is involved in organophosphate, neonicotinoid and pyrethroid differences in susceptibility. Restricted availability of insecticides with different modes of action could favour the selection of resistant phenotypes in stink bug populations.

Field cage trials were carried out in Ponta Grossa, Paraná, season 2010/2011, aiming to characterize and evaluate the injury caused by Edessa meditabunda (F.), Chinavia impicticornis (Stål), and Piezodorus guildinii (West.) (Hemiptera: Pentatomidae) to soybean. Non-infested plants were compared with infested plants with 2 and 3 adults/m (number of adult specimens per linear meter) at the R5.1-R9, R5.3-R9, R6-R9, and R7-R9 soybean growing stages. The following variables were analyzed: foliar retention, seed germination, and injury levels estimated by the tetrazolium test. Foliar retention index ranged from 2.3 to 4.1 in plants infested with P. guildinii and from 2.6 to 3.3 in plants infested with E. meditabunda and C. impicticornis, respectively. The lowest seed germination ranged from 66.5 to 76.5% and was observed in seeds from plants infested with 2 adults of C. impicticornis at R5.3-R9 and 3 adults of P. guildinii (R5.1-R9) and E. meditabunda (R7-R9). The highest average percentage of injury level for seeds occurred with seeds from plants infested at R5.1 with 2 or 3 adults/m of P. guildinii, ranging from 22.6 to 25.0% and from 63.6 to 68.0% in the first and second trials, respectively. Edessa meditabunda caused the highest damage to the seeds of plants infested at R7 (34.0 and 41.4%), and 2 adults/m of C. impicticornis caused the highest number of damaged seeds (54.0%) in plants infested at R6. Although both species were less harmful than P. guildinii, they could be a constraint factor for grain and seed commercialization.

O objetivo deste trabalho foi avaliar a flutuação populacional de Harmonia axyridis em árvores frutíferas, durante dois anos (2004-2006), relacioná-la a variáveis abióticas e avaliar sua influência sobre outros coccinelídeos predadores, em Ponta Grossa, PR. H. axyridis representou 38% dos Coccinellidae. Houve diferença significativa na freqüência relativa da espécie entre os anos de coleta, que passou de 0,20 para 0,67 de um ano ao outro. Houve correlação positiva significativa entre abundância de H. axyridis e temperatura média, nas plantas cítricas, e correlação negativa significativa entre abundância de H. axyridis e umidade relativa do ar, nas plantas não cítricas. H. axyridis exerce impacto negativo sobre as joaninhas locais.

The Neotropical brown stink bug, Euschistus heros (Fabricius) (Hemiptera: Pentatomidae), is a major Brazilian soybean pest. Aiming to provide relevant information to implement pest and insecticide resistance management, new microsatellite loci were developed for E. heros and used in a study of genetic diversity and population structure. The population analysis was performed using eight microsatellite loci from 17 samples (n = 243 individuals) collected in the major soybean‐producing regions in Brazil (northeastern, midwestern, and southern regions). These microsatellite loci provided high genetic diversity values on the whole extension for the studied region (He = 0.895; total number of alleles = 400). Neotropical brown stink bug populations in general displayed low genetic structure levels among the samples (overall ΦST = 0.009). An exception was the sample from the northeastern region, which showed a significant genetic differentiation (pairwise ΦST = 0.031–0.063). Bayesian cluster analysis confirmed these results, did not show population subdivision, and indicated considerable levels of gene flow. Significant correlations between genetic differences and geographic distance were obtained. The lowest estimate of migration was found in the population from São Desidério, which was also the most distant from the remaining populations based on genetic distance. Some plausible hypotheses for the low genetic differentiation among these populations are the fast expansion of soybean production areas, the main food source of E. heros, polyvoltinism, and possible influence of anthropogenic dispersal. All these factors could have led to high population densities, a wide distribution that may contribute to reduced population differentiation, and increased genetic diversity.