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European fruit lecanium, Parthenolecanium corni (Bouché, 1844) is among the leading worldwide pests of fruits such as plums, currants, jostaberry, grapevine and many others. This study is focused on testing the effectiveness of natural insecticide treatments compared with conventional insecticides on overwintering nymphs of the European fruit lecanium. In February of 2017, two experiments were conducted under laboratory conditions. The tested products were Boundary SW® (plant extract), Konflic® (plant extract), Ekol® (canola oil) and a tank-mix of Ekol® + Reldan 22® (canola oil and chlorpyrifos-methyl) as a chemical standard. The most effective product tested was the chemical standard tank-mix of Ekol® and Reldan 22®, which was 100% effective in all experiments. High efficiency was also achieved with Ekol® (canola oil) in high concentrations. We can summarize, that using canola oil in high concentration has almost the same effect as the chemical standard. Using canola oil against European fruit lecanium meets the principles of Integrated Pest Management (IPM) and also the need to design cropping systems that are less dependent on synthetic pesticides.

With the purpose of finding plant compounds with the potential use as herbicides and insecticides, a research was realized with the objective of evaluate the phytotoxic and dissuasive activity of four Chihuahua desert plants. The phytotoxic activity evaluation was tested on Lactuca sativa and Lolium perenne, while the dissuasive activity was realized on three species of phytophagous insects: Myzus persicae, Rhopalosiphum padi and Spodoptera littoralis. Raw extracts were used, the solvents hexane, methanol and ethanol of different plants’ organs (root, steam, leaf and flower) of four species: Fouquieria splendens (ocotillo), Larrea tridentate (governor), Astragalus mollissimus (wild grass) and Pachycereus pecten-aboriginum (echo), by the establishment of in vitro bioassays at a concentration of 10 mg/ml extract/solvent. In the toxicity bioassay, the percentage of germination, root and leaf length were measured. The results showed that the leaf extract of L. tridentata had phytotoxic activity for L. sativa, while for L. perenne the phytotoxicity was observed within the ocotillo, governor and echo extracts. In the dissuasive bioassay, each treatment had 20 repetitions with 10 adult insects per repetition. The methanolic extracts of F. splendens leaf and root, ethanolic extract of A. mollisimus sheet and the ethanolic extract of P. pecten-aboriginum stems showed moderate dissuasive response of feeding against M. persicae, presenting a settlement inhibition index of 53.53, 54.35, 60.00 and 48.84% respectively. Nevertheless, the results indicated that none of the 10 extracts tested on S. littoralis showed significant dissuasive properties for this Lepidoptera, while for R. padi all the tested extracts presented dissuasive properties. The treatments of the four vegetable species evaluated showed defensive or dissuasive properties of moderate to strong feeding against the insects M. persicae and R. padi, presenting interesting potential for being used as insecticides, while the tested extracts that presented phytotoxicity for both lettuce and ryegrass present possibilities for the realization of herbicides.

Abstract: The objective of this work was to assess the fumigant and repellent effects of essential oils on adults of Callosobruchus maculatus and to identify the chemical composition of two of the tested essential oils. For the fumigation test, the oils of Schinus terebinthifolius, Piper aduncum, Syzygium aromaticum, Piper hispidinervum, Cymbopogon citratus, Cinnamomum zeylanicum, and the eugenol compound were tested at different concentrations on C. maculatus adults. For the repellency test, the oils of S. terebinthifolius, P. aduncum, P. hispidinervum, S. aromaticum, Jatropha curcas, and Ricinus communis were evaluated. In the fumigation test, it was observed that P. aduncum and eugenol showed the highest and lowest LC50s, of 169.50 and 0.28 μL L-1 air, respectively. In the repellency test, the oils of S. aromaticum and P. hispidinervum were repellent to C. maculatus. Gas chromatography coupled to mass spectrometry (GC-MS) analysis of these two oils identified 42 compounds, of which safrole was the main component of P. hispidinervum and eugenol of S. aromaticum. The essential oils of S. aromaticum, C. zeylanicum, and the eugenol compound are the most promising to control C. maculatus, via fumigation.

The constant use of chemicals to control pests can cause several problems to the environment andhuman health, accelerate resistance to insect pests and natural enemies mortality. The objective of this study was toestimate the LC50 of neem oil through the effects on mortality and development of larvae of Spodoptera frugiperda(J. E. Smith) (Lepidoptera: Noctuidae). Third instar larvae were individually placed in tubes of rearing containing arectangular portion of maize (Zea mays L.) leaf (variety AL 34) emerged in neem oil solutions at concentrations of0.010; 0.017; 0.077; 0.129; 0.359; 0.599; 1.0%; deltamethrin 25 EC (0.1%) and control (no treatment). Leaves wereimmerged in the treatment solutions for 3 minutes, dried and offered to caterpillars, repeated 20 times in a completelyrandomized design. The evaluations were performed daily by checking the larval and pupal mortality, period (days) ofthe third instar to pupation and pupal period (days), estimating the lethal concentration (LC50) by the Probit method.The neem oil caused 100% mortality of S. frugiperda, at larval or pupal stage, and the LC50 of neem oil of third instarlarvae was 0.213%.

Botanical insecticides have been studied aiming the alternative pest control. The present study investigated the effects of these insecticides on the instantaneous population growth rate (ri) of Aphis gossypii. Botanical insecticides were tested in the following concentrations: Compostonat®, Rotenat-CE® and Neempro (0, 0.50, 0.75, 1.00, 1.25, 1.50 and 1.75%); Natuneem® and Neemseto® (0, 0.25, 0.50, 0.75 and 1.00%) and essential oils of Foeniculum vulgare Mill., Cymbopogom winterianus (L.), Chenopodium ambrosioides L. and Piper aduncum L (0, 0.0125, 0.025, 0.0375 and 0.05%). Cotton leaf discs, CNPA 8H cultivar with 5 cm in diameter were immersed for 30 seconds in products broth and dried for 30 minutes. Eight replicates per concentration were used and each disc was infested with five apterous adult females of A. gossypii uniform in size and confined for 10 days. Compostonat®, Rotenat® and Neempro provided negative ri decreasing A. gossypii population. Natuneem® and Neemseto® and the essential oil of F. vulgare showed positive ri increasing the population. The coefficients of determination (R2) of regression lines ranged from 0.46 to 0.85. The essential oils of C. winterianus, C. ambrosioides and P. aduncum were not statistically significant precluding the establishment of regression lines.Inseticidas botânicos têm sido estudados, visando o controle alternativo de pragas. O presente trabalho objetivou estudar os efeitos desses inseticidas sobre a taxa instantânea de crescimento populacional (ri) de Aphis gossypii. Os inseticidas botânicos foram testados nas seguintes concentrações: Compostonat®, Rotenat-CE® e Neempro (0; 0,50; 0,75; 1,00; 1,25; 1,50 e 1,75%); Nautneem® e Neemseto® (0; 0,25; 0,50; 0,75 e 1,00%); e os óleos essenciais de Foeniculum vulgare Mill., Cymbopogom winterianus (L.), Chenopodium ambrosioides L. e Piper aduncum L. (0; 0,0125; 0,025; 0,0375 e 0,05%). Discos de folhas de algodoeiro, cultivar CNPA 8H, com 5 cm de diâmetro foram imersos por 30 segundos nas caldas dos produtos e secos por 30 minutos. Utilizaram-se oito repetições por concentração, e cada disco foi infestado com cinco fêmeas adultas ápteras de A. gossypii de tamanho uniforme, confinadas durante 10 dias. Compostonat®, Rotenat® e Neempro proporcionaram ri negativas, declinando a população de A. gossypii. Natuneem®, Neemseto® e o óleo essencial de F. vulgare apresentaram ri positivas, aumentando a população. Os coeficientes de determinação (R2) das retas de regressão variaram entre 0,46 a 0,85. Os óleos essenciais de C. winterianus, C. ambrosioides e P. aduncum não apresentaram significância estatística, impossibilitando o estabelecimento das retas de regressão.

Óleos essenciais de Piper aduncum L. e Piper hispidinervum C.DC. (Piperaceae) foram avaliados quanto ao efeito inseticida em Sitophilus zeamais Motsch. por ação de contato, fumigação e tópica. Na determinação da DL50 e CL50, foi utilizada a análise de Probit. Médias porcentuais de mortalidade dos insetos foram comparadas por meio da análise de regressão linear e superposição das barras do erro padrão. S. zeamais foi mais suscetível ao efeito de contato do óleo de P. hispidinervum em relação ao de P. aduncum, obtendo-se CL50 de 0,51 e 2,87 mL cm- 2 de óleo, respectivamente. Mortalidade próxima a 100% foi obtida nas concentrações de 20 e 30% do óleo de P. hispidinervum. Quanto ao efeito fumigante, a susceptibilidade foi maior no óleo de P. aduncum do que no de P. hispidinervum. Houve diferença significativa entre os óleos somente nas concentrações de 0,1 e 1,0. A DL50 foi semelhante nos dois óleos essenciais por aplicação tópica. No entanto, a mortalidade foi maior com P. aduncum. Óleos essenciais de P. aduncum e P. hispidinervum possuem efeito inseticida em S. zeamais, mas as respostas dependem da concentração e do método de exposição a que o inseto seja submetido.Essential oils of Piper aduncum L. and Piper hispidinervum C. DC. (Piperaceae) were tested against Sitophilus zeamais Motsch. Contact, fumigant toxicity and topical effect were tested. Probit analysis was employed in evaluating the LC50 and LD50 response. Linear regression analysis and superposition of the bars (means error standard) were used for comparison of means percentage mortality. S. zeamais was more susceptible to the contact toxicity of the P. hispidinervum oil than P. aduncum oil with LC50 values of 0.51 and 2.87 mL cm-2 of the oil, respectively. The mortality rate was nearly 100% at P. hispidinervum oil concentrations of 20 and 30%. With respect to the fumigant action, the weevil was more susceptible to the P. aduncum oil than to P. hispidinervum. A significant difference between oils mortality was observed only at 0.1 and 1.0% concentrations. For topical effect, similar values of the LD50 were obtained for essential oils. However, the mortality was higher with P. aduncum. Essential oils of the P. aduncum and P. hispidinervum possess insecticidal effect from S. zeamais, but the responses varied according to concentration of the oils and exposure methods.

Spodoptera frugiperda, conhecida como lagarta-do-cartucho, é considerada uma das principais pragas do milho. Como medida alternativa aos agroquímicos, o uso de plantas inseticidas, além de preservar o ambiente, reduz os custos de produção e torna-se uma prática adequada para a agricultura sustentável. Desta forma, o objetivo deste trabalho foi verificar a ação inseticida de extratos aquosos de folhas de eucalipto (Eucaplyptus robusta), guaco (Mikania laevigata)e folhas e frutos de pimenta (Capsicum baccatum). Os extratos a 10% foram incorporados em dieta artificial de Spodoptera frugiperda, mantidas em condições de laboratório (26 ± 2°C, umidade relativa de 60 ± 5% e fotofase de 16 horas). Foram utilizados 5 tratamentos com 4 repetições cada, sendo 15 lagartas por repetição. Avaliaram-se a duração da fase larval, mortalidade diária, peso das lagartas ao 10o dia e das pupas após 24 horas e quantidade de machos e fêmeas. Observou-se que os extratos de E. robustae folhas de C. baccatum resultaram em maior mortalidade e menor peso na fase larval, sendo promissores para testes em campo no controle dessa praga.

Objetivou-se testar a atividade inseticida de pós vegetais em Sitophilus zeamais. Foram testados os pós de Anadenanthera colubrina (folhas); Annona muricata (sementes); Azadirachta inidica (folhas e flores); Caesalpinia pyramidalis (folhas), Chenopodium ambrosioides (folhas e flores); Cymbopogon sp. (folhas); Cymbopogon citratus (folhas); Momordica charantia (folhas e frutos); Piper nigrum (sementes); e Ricinus communis (folhas). Além disso, avaliou-se o potencial inseticida de folhas e flores de C. ambrosioides em diferentes dosagens. Na avaliação de repelência foi estabelecido um índice de preferência, e utilizado o teste t para comparação das médias das espécies vegetais. Também foi realizada a comparação das médias das plantas que foram classificadas como repelentes. Para avaliação da mortalidade, procedeu-se a análise de variância e a comparação das médias pelo teste de Tukey e também o teste t para comparação das médias dos tratamentos C. ambrosioides e P. nigrum. Os dados de emergência foram analisados pelo teste de Tukey. Para avaliar os dados de mortalidade, ocasionados por C. ambrosioides, determinou-se a CL50 utilizando a análise de Probit. Os dados de emergência foram verificados pela análise de regressão. As plantas que provocaram repelência foram Cymbopogon sp., C. citratus e C. ambrosioides. A planta que mais afetou a sobrevivência da praga foi C. ambrosioides, que provocou mortalidade total dos insetos infestantes e nenhuma emergência. Adultos de S. zeamais são mais suscetíveis a concentração de 0,125 g do pó de C. ambrosioides.

ABSTRACT For an important and expensive crop such as corn, the resistance of Spodoptera frugiperda J.E. Smith to various pesticides has led to research throughout the world for a potential insecticide from a natural source. For the management of pest resistance, natural compounds associated with synthetic insecticides can be a promising tool because they can reduce the application of the synthetics molecules while maintaining their effectiveness and promoting the control of the pests. Linalool is a potential insecticide that is easily obtained because it is found in high concentrations in the essential oil of Ocimum basilicum L. Therefore, the present study aimed to evaluate the toxicity of this essential oil and its combination with deltamethrin to control S. frugiperda. Through dose response assays, the acute toxicities (LD50) of the essential oil and deltamethrin were estimated. Additionally, the combination of these materials was also assessed, attaining a reduction of 80% of the LD50 of deltamethrin while obtaining the same result as when the pyrethroid was administered alone. From these results, it is expected that the combination of natural compounds and synthetic insecticides will be a promising practice, helping to manage resistance while reducing the environmental impact of toxic compounds.