Podisus nigrispinus Dallas (Heteroptera: Pentatomidae), released in biological control programs, is a predator of Lepidopteran and Coleopteran species. Lemongrass essential oil and its constituents can be toxic to this natural enemy. The major constituents of lemongrass essential oil are neral (31.5%), citral (26.1%), and geranyl acetate (2.27%). Six concentrations of lemongrass essential oil and of its citral and geranyl acetate constituents were applied to the thorax of P . nigrispinus nymphs and adults. The walking and respiratory behavior of the P . nigrispinus third-instar nymphs, treated with citral and geranyl acetate at the LD 50 and LD 90 doses, were analyzed with video and respirometer. The lemongrass essential oil toxicity increased from first- to fifth-instar P . nigrispinus nymphs. The P . nigrispinus respiration rates (μL de CO 2 h −1 /insect) with citral and geranyl acetate in the LD 50 and LD 90 differed. Nymphs exposed to the lemongrass essential oil and its constituents on treated surfaces presented irritability or were repelled. Podisus nigrispinus adults were tolerant to the lemongrass essential oil and its constituents, geranyl acetate and citral. The altered respiratory activity with geranyl acetate and the fact that they were irritated and repelled by citral suggest caution with regard to the use of the lemongrass essential oil and its constituents in integrated pest management incorporating this predator, in order to avoid diminishing its efficiency against the pests.

The relationship between pests and natural enemies using multivariate analysis on cotton in different spacing has not been documented yet. Using multivariate approaches is possible to optimize strategies to control Aphis gossypii at different crop spacings because the possibility of a better use of the aphid sampling strategies as well as the conservation and release of its natural enemies. The aims of the study were (i) to characterize the temporal abundance data of aphids and its natural enemies using principal components, (ii) to analyze the degree of correlation between the insects and between groups of variables (pests and natural enemies), (iii) to identify the main natural enemies responsible for regulating A. gossypii populations, and (iv) to investigate the similarities in arthropod occurrence patterns at different spacings of cotton crops over two seasons. High correlations in the occurrence of Scymnus rubicundus with aphids are shown through principal component analysis and through the important role the species plays in canonical correlation analysis. Clustering the presence of apterous aphids matches the pattern verified for Chrysoperla externa at the three different spacings between rows. Our results indicate that S. rubicundus is the main candidate to regulate the aphid populations in all spacings studied.

the toxicity of essential oils that can be used in insect pest management to pollinators needs further studies. Apis mellifera Linnaeus and Trigona hyalinata (Lepeletier) (Hymenoptera: Apidae) foragers were exposed by three pathways to ginger, mint, oregano and thyme essential oils to provide their Lc 50, LD 50 and Lc 90, LD 90 . oregano and thyme were more toxic through contact and topically for A. mellifera while the toxicity of mint and ginger was lower. Trigona hyalinata was more tolerant to the essential oils than A. mellifera. in the walking test, the area was treated (totally or partially) with sub-doses (Lc 50 ) obtained via contact. the area fully treated with oregano reduced the distance traveled and the movement speed increased the number of stops by A. mellifera. Similar results were observed for T. hyalinata with oregano and thyme oils. Apis mellifera showed irritability remaining shorter time in the area partially treated with ginger, mint and thyme essential oils while T. hyalinata had similar behavior with ginger and thyme. essential oils did not repel A. mellifera or T. hyalinata, but those of ginger, mint and thyme reduced the time spent by A. mellifera in areas treated with sublethal doses. oregano and thyme essential oils reduced the survival, mainly, of A. mellifera, while ginger and mint were selective for both pollinators.Bees are essential for plant propagation 1 , but factors such as pathogens, habitat losses and intensive pesticide use are reducing their populations 2 . The decline of bee colonies, known as Colony Collapse Disorder (CCD), threatens pollination and the production of honey, propolis, royal jelly, and wax 3,4 . Bees are exposed to insecticides during the pollen and nectar harvesting through contact with the treated plant surface and the ingestion of sap from seeds coated with systemic insecticides 5,6 abamectin, acetamiprid, cartap-hydrochloride, chlorfenapyr, deltamethrin and thiamethoxam were toxic to Apis mellifera Linnaeus, 1758 (Hymenoptera: Apidae) workers by direct spraying; diet treated and contact with pulverized leaves 2 . Larvae mortality was high and adult mobility of Melipona quadrifasciata Lepeletier, 1836 (Hymenoptera: Apidae) low with diet treated with imidacloprid 7 . These insecticides act on arthropods, causing physiological and behavioral effects by directly interfering in the acetylcholine receptors 7 . In addition, insecticides may affect learning, foraging, growth, besides pupa malformation, adult emergence and reproduction 8,9 and caused irritability and repelled bees 7 . Residues in wax, nectar and pollen reduce the quality and value of these products 4 .The vulnerability of A. mellifera to pesticides has been studied 2,10 but the effect of these products on native stingless bees such as Trigona hyalinata (Lepeletier) (Hymenoptera: Apidae) is little understood. The development period of stingless bees is generally longer than that of Apis spp., and, therefore, their survival is more under

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The increase of agricultural areas with glyphosate-resistant (GR) crops, and use of this herbicide in Brazil, makes necessary to assess its impacts on non-target organisms. The objective was to evaluate the development, reproduction and life table parameters of Podisus nigrispinus (Heteroptera: Pentatomidae) reared on GR-soybean plants treated with glyphosate formulations (Zapp-Qi, Roundup-Transorb-R and Roundup-Original) at the recommended field dose (720g acid equivalent ha). Glyphosate formulations had no affect on nymph and adult weight of this predator. Fourth instar stage was shortest with Zapp Qi. Egg-adult period was similar between treatments (26 days) with a survival over 90%. Zapp-Qi and Roundup-Transorb-R (potassium-salt: K-salt) reduced the egg, posture and nymph number per female, and the longevity and oviposition periods of this predator. Podisus nigrispinus net reproductive rate was highest in GR-soybean plants treated with Roundup-Original (isopropylamine-salt: IPA-salt). However, the duration of one generation, intrinsic and finite increase rates, and time to duplicate the population, were similar between treatments. Glyphosate toxicity on P. nigrispinus depends of the glyphosate salt type. IPA-salt was least harmless to this predator. Formulations based on K-salt altered its reproductive parameters, however, the development and population dynamic were not affect. Therefore, these glyphosate formulations are compatible with the predator P. nigrispinus with GR-soybean crop.

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