The aim of this work was to study the life cycle of Cosmolaelaps jaboticabalensis Moreira, Klompen and Moraes preying on Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), a serious cosmopolitan pest of different crops, as well as on Protorhabditis sp. (Nematoda: Rhabditidae) and Tyrophagus putrescentiae (Astigmatina: Acaridae), prospective factitious foods for the mass rearing of the predator. Experiments were conducted in a chamber at 25 ± 1 °C, 70 ± 10 % RH and in the dark. Total immature development (egg-adult) was completed in 12.3 ± 5, 6.6 ± 0.6 and 7.1 ± 0.6 on F. occidentalis, Protorhabditis sp. and T. putrescentiae, respectively. Fecundity and intrinsic rate of increase were higher on Protorhabditis sp. (71.6 ± 9.1 eggs/female; 0.28 female/female/day) than on F. occidentalis (63.8 ± 14.8; 0.23) and T. putrescentiae (43.1 ± 8.9; 0.23). Cosmolaelaps jaboticabalensis reproduces by thelytokous parthenogenesis and its larval stages can be completed without feeding. Protonymphs and deutonymphs can survive in the absence of food for about a month, and adults for almost 2 months. It was concluded that C. jaboticabalensis is a promising biological control agent of F. occidentalis and that it may be mass reared with the use of Protorhabditis sp. or T. putrescentiae.

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The parasitoid Ageniaspis citricola Longvnovskaya is a main biological control agent of the citrus leafminer Phyllocnistis citrella Stainton, an insect pest that causes considerable damage to citrus worldwide. However, the use of pesticides to control arthropod pests can reduce the effectiveness of parasitoids and disrupt integrated pest management in citrus groves. This study evaluated the impact on A. citricola of five insecticides that are used to control arthropod pests in citrus. Our results indicated that imidacloprid, chlorpyrifos, bifenthrin and β-cyfluthrin were harmful (mortality >89 %) to A. citricola adults; whereas abamectin did not cause significant mortality and was considered harmless to the parasitoid. In addition to causing high mortality, imidacloprid and bifenthrin were considered moderately persistent, because they caused <25 % mortality to 17 and 24 days after spraying (DAS), respectively. Chlorpyrifos and β-cyfluthrin were considered slightly persistent (mortality <25 %, 7 DAS). Although abamectin was considered harmless to A. citricola adults, had a short life (mortality <25 %, 3 DAS), and did not significantly affect the parasitism rate, the number and viability of pupae, or the longevity of A. citricola, this insecticide significantly reduced the proportion of females in the progeny compared to the control treatment. Therefore, semi-field and field studies that consider demographic parameters are needed to evaluate the impacts of these insecticides on the A. citricola parasitoid.

The species and varieties of citrus plants that are currently grown can favor the population growth of the citrus red mite Panonychus citri (McGregor) (Prostigmata: Tetranychidae) and alter the pest management programs in citrus groves. In this study we evaluated, in the laboratory, the development and reproduction of P. citri and estimated its life table parameters when reared on four varieties of Citrus sinensis (L.) Osbeck (Valencia, Pera, Natal, and Hamlin), one variety of Citrus reticulata Blanco (Ponkan) and one variety of Citrus limon (L.) Burm. (Sicilian). The incubation period and egg viability were not affected by the host plant. However, the development and survival of the immature stage were significantly lower on Hamlin orange than on Valencia, Pera and Natal oranges, Ponkan mandarin and Sicilian lemon. The fecundity and oviposition period of females were lower on Hamlin orange than on the other hosts. Mites reared on Valencia orange and Sicilian lemon had a higher net reproductive rate (R 0 ), intrinsic growth rate (r) and finite rate of increase (λ), and a shorter interval between generations (T) than on Pera, Natal and Hamlin oranges and Ponkan mandarin. On the other hand, mites reared on Hamlin orange had the lowest R 0 , r and λ and the highest T among the hosts. Based on the results obtained we recommend that for Valencia orange and Sicilian lemon, the mite monitoring programs should be more intense to detect the initial infestation of pest, avoiding the damage in plants and the increase in production costs.

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Food production to meet human demand has been a challenge to society. Nowadays, one of the main sources of feeding is soybean. Considering agriculture food crops, soybean is sixth by production volume and the fourth by both production area and economic value. The grain can be used directly to human consumption, but it is highly used as a source of protein for animal production that corresponds 75% of the total, or as oil and derived food products. Brazil and the US are the most important players responsible for more than 70% of world production. Therefore, a reliable forecasting is essential for decision-makers to plan adequate policies to this important commodity and to establish the necessary logistical resources. In this sense, this study aims to predict soybean harvest area, yield, and production using Artificial Neural Networks (ANN) and compare with classical methods of Time Series Analysis. To this end, we collected data from a time series (1961–2016) regarding soybean production in Brazil. The results reveal that ANN is the best approach to predict soybean harvest area and production while classical linear function remains more effective to predict soybean yield. Moreover, ANN presents as a reliable model to predict time series and can help the stakeholders to anticipate the world soybean offer.

The generalist predator Ceraeochrysa cincta (Schneider) (Neuroptera: Chrysopidae) is an important biological control agent of several arthropod pests in different agroecosystems. This study assessed the lethal and sublethal effects of six insect growth regulators sprayed on first-instar larvae of C. cincta. Lufenuron and diflubenzuron were highly harmful to first-instar larvae of C. cincta, causing 100 % of mortality before they reached the second instar. Buprofezin caused ~25 % mortality of the larvae and considerably reduced the fecundity and longevity of the insects, but substantially increased the proportion of females in the surviving population of C. cincta. Methoxyfenozide and tebufenozide did not affect the duration and survival of the immature stages, but methoxyfenozide significantly reduced the fecundity and longevity of the insects. Pyriproxyfen reduced the survival of the larval stage by 19.5 %, but did not affect the development, survival and reproduction of the surviving individuals. Based on reduction coefficient, the insecticides diflubenzuron and lufenuron were considered harmful to C. cincta, whereas buprofezin and methoxyfenozide were slightly harmful and tebufenozide and pyriproxyfen were harmless. The estimation of life-table parameters indicated that buprofezin and methoxyfenozide significantly reduced the R o , r and λ of C. cincta, whereas pyriproxyfen and tebufenozide caused no adverse effect on population parameters, indicating that these insecticides could be suitable for use in pest management programs towards the conservation and population increase of the predator in agroecosystems. However, more studies should be conducted to evaluate the compatibility of these insecticides with the predator C. cincta under semi-field and field conditions.

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