Insecticidal potential of organic extracts of Calotropis procera to Spodoptera frugiperda

This study evaluated the toxic effects of organic extracts of Calotropis proceraleaves on the survival, development, and reproduction of Spodoptera frugiperda. Solutions of crude methanol extract and hexane and methanol fractions of C. proceraleaves were added at 1.15% and 2.14% concentrations to the artificial diet of S. frugiperda. The mortality and duration of larval and pupal phases, weights of female and male pupae, deformations of pupae and adults, the reduction of adults able to reproduce, pre-oviposition and oviposition periods, the number of postures per female, and the fecundity and fertility of S. frugiperdafemales were also evaluated. The extracts harmed the survival, development, and reproduction of S. frugiperda. The ingestion of extracts and fractions by caterpillars affected adults by decreasing the oviposition period, the number of postures, fecundity, and fertility. The crude MeOH extract at a2.14% concentration harmed the evaluated parameters of the insect, except for pupal mortality, female pupae weight, and pre-oviposition period. The MeOH fraction at 2.14% caused a 50.0% mortality of caterpillars and 16.0% deformation in pupae and 33.0% inadults, reducing by 72.0% the population able to reproduce. The MeOH fraction at the 2.14% concentration caused 25.0% and 38.0% of pupal mortality and deformation, respectively. Calotropis procerahas promising insecticidal properties for a biological insecticide, a convenient and sustainable strategy for protecting plants against S. frugiperda.

Multiple resistance to primary pests of grain sorghum hybrids: Spodoptera frugiperda (Lepidoptera: Noctuidae), Diatraea saccharalis (Lepidoptera: Crambidae), and Diceraeus melacanthus (Hemiptera: Pentatomidae)

ABSTRACT Plant resistance is an important tactic within the precepts of Integrated Pest Management, and the existence of grain sorghum hybrids with multiple insect resistance could benefit crop management and sustainability. This study evaluated the susceptibility of 30 grain-sorghum hybrids to three major pests, namely, fall armyworm (FAW) Spodoptera frugiperda, sugarcane borer (SCB) Diatraea saccharalis, and green-belly stink bug (GBS) Diceraeus melacanthus. The hybrids were cultivated and experiments with each insect species were conducted separately in a greenhouse. For FAW, visual injury assessments were performed on plants 7 and 14 days after infestation (DAI). For SCB, insect presence and injury were assessed 40 DAI. For GBS, the plants were evaluated using a damage rating scale 12, 19, and 26 DAI. Cluster analysis allowed separating the grain sorghum hybrids into groups regarding the levels of resistance to each pest. Hybrid BRS373 stood out as moderately resistant to FAW; AG1090, 80G20, BRAVO, BRS373, AG1615, and IG220 were the most promising for SCB; and for GBS, hybrids 50A40, A9735R, JADE, ENFORCER, BUSTER, 50A10, and IG244 were the most nominated. This information will significantly aid sorghum breeding programs focused on developing commercial hybrids that comprise both insect-resistance and high-yield characteristics. However, further research should evaluate potential chemical and morphological plant traits underlying the lower levels of susceptibility to FAW, SCB, and GBS found in the selected sorghum hybrids.

A 6-year field monitoring of fall armyworm, Spodoptera frugiperda, in transgenic Bt maize in Brazil

ABSTRACT A 6-year field monitoring study was designed to compare the presence of fall armyworm Spodoptera frugiperda (J. E. Smith), leaf injury, its parasitoids, 100 seed weight, and seed yield of Bt maize hybrids approved for commercialization in the Brazilian market. Field trials were planted in two municipalities, divided into two periods, from 2011 to 2014 (period I), and due to the approval of different Bt hybrids, from 2015 to 2016 (period II). Treatments were Bt, non-Bt maize and all non-Bt maize sprayed with insecticide methomyl. Six Bt-maize hybrids were planted, expressing the following proteins: Cry1Ab, Cry1F, Cry1A.105 (Cry1Ab +Cry1Ac +Cry1F), Cry2Ab2a and Vip3. In 2015 and 2016 Bt Powercore was planted due to its commercial approval. The number of S. frugiperda larvae for most Bt hybrids was lower than on non-Bt hybrids, except for Fórmula TL and Herculex in period II, in both municipalities. In period I, Bt hybrids VT, VT 2 and Viptera showed almost no injury on their leaves, despite the high number of fall armyworm larvae found in plants. Different parasitoids emerged from larvae from Bt and non Bt hybrids: Archytas sp., Campoletis sp., Chelonus sp., Eiphosoma sp. and Ophion luteus. The average 100 seed weight was higher in municipality from Sete Lagoas for all Bt hybrids, non-Bt hybrids and non-Bt hybrids sprayed with methomyl, when compared to Nova Porteirinha during period I. Fórmula TL, non-Bt Fórmula TL sprayed with methomyl, and non-Bt Fórmula TL showed the lowest seed yield in both municipalities and periods.

Description of a bilateral gynandromorph in Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) from Brazil

ABSTRACT A bilateral gynandromorph of Spodoptera frugiperda was reported for the first time from Minas Gerais State, Brazil. The specimen with this trait was found among the progeny of a laboratory rearing population and exhibited dimorphism in the antennae, wings, head, thorax, and abdomen. It had a male left side and a female right side. Both the external and internal genitalia were typically those of a male.

Identificación de un aislamiento argentino de Spodoptera frugiperda granulovirus / Identification of an Argentinean isolate of Spodoptera frugiperda granulovirus

Abstract The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is an important maize pest. Due to the environmental impact and emergence of resistance caused by chemical pesticides and transgenic events, the use of baculoviruses becomes a safe and useful alternative for its control in integrated pest management strategies. Here we report the identification of a novel isolate of a granulovirus of S. frugiperda native to the central region of Argentina, named SfGV ARG. We observed that larvae infected with SfGV ARG showed a yellowish coloration, swollen body and, in some cases, severe lesions in the last abdominal segments. We confirmed the identity of the isolate by sequencing fragments of the lef-8, lef-9 and granulin genes and by calculating evolutionary distances using the Kimura-2-Parameter model. SfGV ARG DNA restriction pattern allowed to estimate a genome of at least 135 kb.

Resumen La oruga militar tardía, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), es una plaga importante del maíz. Debido al impacto ambiental y a la aparición de resistencia causados por los pesticidas químicos y los eventos transgénicos, el uso de baculovirus resulta una alternativa útil y saludable para su control en estrategias de manejo integrado de plagas. En este trabajo reportamos la identificación de un nuevo aislamiento del granulovirus de la S. frugiperda nativo de la región central de Argentina, SfGV ARG. Se observó que larvas infectadas con SfGV ARG mostraron coloración amarillenta, hinchazón y, en algunos casos, lesiones graves en los últimos segmentos abdominales. Se confirmó la identidad del aislamiento por secuenciación de fragmentos de los genes lef-8, lef-9y granulina, y por cálculo de distancias evolutivas usando el parámetro de Kimura-2. El patrón de restricción generado con el ADN genómico de SfGV ARG permitió estimar un tamaño de genoma de al menos 135 kb.

Preference of Neoseiulus californicus (Acari: Phytoseiidae) for volatiles of Bt maize induced by multiple herbivory

ABSTRACT Plant indirect induced defenses against herbivores are characterized by the production of plant volatiles that to attract natural enemies. The objective of this study was to evaluate whether the attack of the two-spotted spider mite Tetranychus urticae or the multiple herbivory of T. urticae together with the fall armyworm Spodoptera frugiperda are able to elicit indirect induced defense in conventional and Bt maize plants. The experiment was carried out in the laboratory using Y-tube olfactometer, evaluating the predatory mite Neoseiulus californicus olfactory preference for plant volatiles. The treatments involved: Clean Conventional Plant; Conventional Plant Infested with T. urticae; Clean Bt Plant; Bt Plant Infested with T. urticae; Conventional Plant Infested with T. urticae + fall armyworm; Bt Plant Infested with T. urticae + fall armyworm. For the chemical analyzes the Trace GC Ultra gas chromatograph was used, paired with the Polaris Q mass spectrometer, GC - MS system. Neoseiulus californicus was also unable to distinguish between volatiles from both conventional and Bt infested maize plants. Moreover, there was no discrimination of the predator mite between plants under single and multiple infestations, both in conventional and Bt maize. When comparing conventional and Bt plants, both with multiple infestation, the predator mite N. californicus had no preference among these sources of odors. However, there was observed chemical changes of the volatiles among the groups of plants studied. Thus, it is suggested that the groups of plants under study have chemical modifications, but they are not able to attract N. californicus. In addition, Bt plants response was similar to conventional plants on attracting N. californicus.

Effect of seed treatment with insecticides on the control of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in soybean / Efeito do tratamento de sementes com inseticidas no controle de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) na cultura da soja

Fall armyworm is one of the main insect pests in Brazil. Thus, the present work aimed to evaluate the seed treatment effect on the control of Spodoptera frugiperda in initial infestations of soybean crops. The experimental design was completely randomized with four replicates of six insecticide treatments applied through seed treatment: imidacloprid plus thiodicarb at the dose of 52.5 plus 105 g a.i. (active ingredient) 100 kg-1 of seed (Cropstar® 0.350 L 100 kg-1 of seed); thiamethoxam at 105 g a.i. 100 kg-1 of seed (Cruiser 350 FS® 0.3 L 100 kg-1 of seed); chlorantraniliprole at 62.5 g a.i. 100 kg-1 of seed (Dermacor® 0.1 L 100 kg-1 of seed); cyantraniliprole at 120 g a.i. 100 kg-1 of seed (Fortenza 600 FS® 0.2 L 100 kg-1 of seed); fipronil plus pyraclostrobin and thiophanate-methyl 50 + 5 + 45 g a.i. 100 kg-1 of seed (Standak Top® 0.2 L 100 kg-1 of seed), and a control treatment. The experiment was carried out in a greenhouse. Diamide insecticides (chlorantraniliprole and cyantraniliprole) presented the best results among all treatments, with lower consumption of the treated leaves by the caterpillars and greater control efficacy of this insect. We verified that seed treatment is a viable alternative for controlling S. frugiperda at the beginning of crop development, when the caterpillar presents the behavior of cutting the seedlings and/or the consumption of leaf area, causing a reduction in the plant population and a consequent yield loss.(AU)

A lagarta-do-cartucho é um dos principais insetos-praga no Brasil. Assim, o presente trabalho teve por objetivo avaliar o efeito do tratamento de sementes no controle de Spodoptera frugiperda nas infestações iniciais da cultura da soja. O delineamento experimental foi inteiramente casualizado, com quatro amostras replicadas de seis tratamentos inseticidas aplicados via tratamento de sementes: imidacloprida mais tiodicarbe na dose de 52,5 mais 105 g i.a. (ingrediente ativo) 100 kg-1 de sementes (Cropstar® 0,350 L 100 kg-1 de sementes); tiametoxam a 105 g i.a. 100 kg-1 de sementes (Cruiser 350 FS® 0,3 L 100 kg-1 de sementes); clorantraniliprole a 62,5 g i.a. 100 kg-1 de sementes (Dermacor® 0,1 L 100 kg-1 de sementes); ciantraniliprole a 120 g i.a. 100 kg-1 de sementes (Fortenza 600 FS® 0,2 L 100 kg-1 de sementes); fipronil mais piraclostrobina e tio-fanato-metílico 50 + 5 + 45 g i.a. 100 kg-1 de sementes (Standak Top® 0,2 L 100 kg-1 de sementes) e um tratamento controle. O experimento foi conduzido em uma vegetação. Dentre todos os tratamentos, os inseticidas do grupo químico das diamidas (clorantraniliprole e ciantraniliprole) apresentaram os melhores resultados, com consumo inferior pelas lagartas das folhas tratadas e maior eficiência de controle deste inseto. Foi constatado que o tratamento de sementes é uma alternativa viável para o controle de S. frugiperda no início do desenvolvimento da cultura, quando a lagarta apresenta o comportamento de cortar as plântulas e/ou consumir área foliar, ocasionando uma redução da população de plantas e uma consequente perda de produtividade.(AU)

Aqueous extract of pequi fruit to control Spodoptera frugiperda in corn / Extrato aquoso de fruto de pequizeiro para o controle de Spodoptera frugiperda em milho

Pequi fruit peels contain steroids, triterpenes, flavonoids, tannins, and saponins, compounds that are potentially useful for integrated pest management. As such, the aim of this study was to evaluate the insecticidal activity of aqueous extracts of pequi fruit peels on Spodoptera frugiperda. Field-grown corn plants of the cultivar 'Al Alvaré' were sprayed with extract concentrations of 0.8%, 2.5%, 5%, and 10% (v/v) 40 and 47 days after germination. The pequi peels were chopped, oven dried (65°C for 72 hours), and ground in a grinding mill. The resulting powder was used to prepare a base-line extract (10%), and the other concentrations evaluated were prepared by diluting this extract. The intensity of the damage caused by S. frugiperda caterpillars was evaluated 43, 46, 50, and 53 days after germination, using a visual scoring scale. Application of the extract decreased the amount of damage caused by the caterpillars. The 5% extract concentration was the most effective, while the 10% extract concentration showed evidence of phytotoxicity after the second spraying. These results suggest that the pequi extract is toxic to the S. frugiperda caterpillars and can be used for the management of this pest.(AU)

Nas cascas dos frutos de pequi já foram identificados esteroides, triterpenos, flavonoides, taninos e saponinas, substâncias promissoras no manejo integrado de pragas. Com base nesta informação, objetivou-se com este trabalho avaliar a ação inseticida de extratos aquosos das cascas dos frutos de pequi a Spodoptera frugiperda. O ensaio foi realizado em campo, utilizando sementes de milho do cultivar 'AL Alvaré' que aos 40 e 47 dias após a germinação foram pulverizadas com concentrações dos extratos de 0,8%, 2,5%, 5% e 10% (v/v). Os extratos foram preparados a partir de cascas dos frutos de pequi que, após picadas, foram secas em estufa (65°C, por 72 horas) e moídas em moinho de facas. Com o pó foi preparado um extrato padrão (10,0%). As demais concentrações foram obtidas a partir deste extrato. Foram avaliadas a intensidade das injúrias causadas pelas lagartas de S. frugiperda em plantas com 43, 46, 50 e 53 dias, utilizando uma escala visual de notas. As pulverizações dos extratos reduziram o número de injúrias provocadas pelas lagartas. A concentração de 5% foi a mais eficiente nesta redução e a de 10% causou fitotoxicidade após a segunda pulverização. O extrato pequi é tóxico às lagartas de S. frugiperda e pode ser utilizado no manejo desta praga.(AU)

Ocimum basilicum essential oil combined with deltamethrin to improve the management of Spodoptera frugiperda / Óleo essencial de Ocimum basilicum associado à deltametrina no manejo de Spodoptera frugiperda

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.

RESUMO Para uma cultura importante e expressiva como o milho, a resistência de Spodoptera frugiperda J.E. Smith a vários inseticidas atraiu a atenção no mundo para pesquisar o potencial inseticida de compostos naturais. Para o manejo da resistência, os compostos naturais associados a inseticidas sintéticos podem ser uma ferramenta promissória por reduzirem a aplicação das moléculas sintéticas para que não percam sua eficácia, além de promover o controle das pragas. O linalol é um terpenoide considerado como inseticida potencial, pode ser facilmente obtido naturalmente uma vez que é encontrado em alta concentração no óleo essencial de Ocimum basilicum. Portanto, o presente estudo teve como objetivo avaliar a toxicidade deste óleo essencial e sua combinação com deltametrina no controle de Spodoptera frugiperda. Através do ensaio de dose-resposta, foi estimada a toxicidade aguda (DL50) do óleo essencial e da deltametrina. Adicionalmente, foi também avaliada a combinação entre ambos, alcançando uma redução de 80% da DL50 de deltametrina para se obter o mesmo resultado quando o piretroide foi administrado sozinho. A partir dos nossos resultados, espera-se que uma combinação de uso de compostos naturais e inseticidas sintéticos possa ser uma prática promissora, auxiliando no manejo da resistência de pragas e principalmente reduzindo os impactos ambientais de compostos tóxicos.

Biological Activity of Piper aduncum extracts on Anticarsia gemmatalis (Hübner) (Lepidoptera: Erebidae) and Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

ABSTRACT Piper aduncum found naturally in the Amazon and southeastern Brazil, is known for its secondary metabolites that have activity on insects. Anticarsia gemmatalis and Spodoptera frugiperda are among the major insect pests associated with agricultural production. This research evaluated the biological activity of hexane, ethyl acetate, and ethanol extracts of P. aduncum leaves on mortality and duration of larval and pupal periods, as well as weight, width, and length of A. gemmatalis and S. frugiperda pupae. The mortality of A. gemmatalis larvae in trials with P. aduncum extracts were 93.3% (hexane) and 90% (ethyl acetate), estimating LC50 of 6.35 and 5.79 mg/mL, respectively. Mortality in S. frugiperda submitted to the hexane extract ranged from 3.33% to 96.66% (LC50 of 8.22 mg/mL). The ethanol extract induced low mortality (3.33% to 23.33%). The P. aduncum extracts did not affect the development of S. frugiperda pupae. In A. gemmatalis differences in weight and length occurred. The chemical characterization was by GC-MS, which revealed that the major constituent in the hexane extract of P. aduncum was apiol (90.7%). P. aduncum extracts are important and promising components to manage A. gemmatalis and S. frugiperda, which cause extensive production losses.

First record of Peckia (Sarcodexia) lambens (Wiedemann, 1830) (Diptera: Sarcophagidae) parasitizing Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) in Brazil / Primeiro registro de Peckia (Sarcodexia) lambens (Wiedemann, 1830) (Diptera: Sarcophagidae) parasitando Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) no Brasil

Collections of larvae of Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) carried out in the field in three localities in the city of Campo Grande, Mato Grosso do Sul, Brazil, from October 2012 to March 2014, recorded the presence of three species of Diptera parasitizing Spodoptera frugiperda: two species of Tachinidae, Achytas incertus (Macquart, 1851) and Winthemia trinitatis Thompson, 1963, and one species of Sarcophagidae, Peckia (Sarcodexia) lambens (Wiedemann, 1830). The latter is identified for the first time parasitizing S. frugiperda in Brazil.(AU)

Coletas de larvas de Spodoptera frugiperda (Smith, 1797) (Lepidoptera: |Noctuidae) realizadas no campo em três localidades da cidade de Campo Grande, Mato Grosso do Sul, Brasil, entre outubro de 2012 e março de 2014, registraram a presença de três espécies de Diptera como parasitoide de S. frugiperda: duas espécies de Tachinidae, Archytas incertus (Macquart, 1851) e Winthemia trinitatis Thompson, 1963, e uma espécie de Sarcophagidae, Peckia (Sarcodexia) lambens (Wiedemann 1830), sendo esta identificada pela primeira vez no país como parasitoide larval de S. frugiperda.(AU)

Larval development of Spodoptera eridania and Spodoptera frugiperda fed on fresh ear of field corn expressing the Bt proteins (Cry1F and Cry1F + Cry1A.105 + Cry2Ab2) / Desenvolvimento larval de Spodoptera eridania e Spodoptera frugiperda alimentadas com espigas de milho verde expressando proteínas Bt (Cry1F e Cry1F + Cry1A.105 + Cry2Ab2)

ABSTRACT: The objective of this study was to evaluate extent of larval period, larval survival (%), food consumption, and pupal biomass of Spodoptera eridania and Spodoptera frugiperda (Lepidoptera: Noctuidae ) fed on fresh ears of field corn expressing Bt proteins (Cry1F and Cry1F+Cry1A.105+Cry2Ab2). Larvae of Spodoptera spp. survived less than two days when they consumed Bt corncobs and showed 100% mortality. Spodoptera eridania reared on non-Bt corn cobs showed higher larval development (21.6 days) than S. frugiperda (18.4 days) and lower viability (56.4% and 80.2% for S. eridania and S. frugiperda , respectively). A higher amount of corn grains was consumed by S. eridania (5.4g) than by S. frugiperda (3.9g). In summary, this study demonstrated that the toxins Cry1F and Cry1F + Cry1A.105 + Cry2Ab2 expressed in fresh corn cobs contributed to protect ears of corn against S. frugiperda and the non-target pest S. eridania . However, itis important to monitor non-Bt cornfields because of the potential of both species to cause damage to ear sof corn.

RESUMO: Este estudo teve como objetivo avaliar o período de desenvolvimento larval, sobrevivência larval (%), consumo de alimento e biomassa pupalde Spodoptera eridania e Spodoptera frugiperda (Lepidoptera: Noctuidae ), alimentadas com grãos verdes de milho Bt que expressam as proteínas Cry1F e Cry1F + Cry1A.105 + Cry2Ab2). As larvas de Spodoptera spp. alimentadas com milho Bt sobreviveram por até dois dias, registrando-se 100% de mortalidade. A espécie S. eridania alimentada com grãos de milho não Bt apresentou um maior desenvolvimento larval (21,6 dias) do que S. frugiperda (18,4 dias), e menor viabilidade larval (56,4% e 80,2% para S. eridania e S. frugiperda respectivamente). Uma maior taxa de consumo de grãos foi observada para S. eridania (5,4g) do que para S. frugiperda (3,9g). Em síntese, este estudo comprova que as toxinas Cry1F e Cry1F + Cry1A.105 Cry2Ab2 expressas em grãos imaturos de milho contribuem na proteção das espigas de milho contra S. frugiperda e a praga não-alvo S. eridania , entretanto, é importante monitorar as lavouras cultivadas com milho não Bt, devido o potencial de ambas as espécies em ocasionar danos nas espigas da planta.

Biological activity of Bt proteins expressed in different structures of transgenic corn against Spodoptera frugiperda / Atividade biológica de proteínas Bt expressas em diferentes estruturas de milho transgênico em Spodoptera frugiperda

ABSTRACT: Spodoptera frugiperda (J. E. Smith) is the main target pest of Bt corn technologies, such as YieldGard VT PRO(tm) (Cry1A.105/Cry2Ab2) and PowerCore(tm) (Cry1A.105/Cry2Ab2/Cry1F). In this study, it was evaluated the biological activity of Bt proteins expressed in different plant structures of YieldGard VT PRO(tm) and PowerCore(tm) corn against S. frugiperda . Complete mortality of S. frugiperda neonates was observed on leaf-disc of both Bt corn technologies. However, the mortality in silks and grains was lower than 50 and 6%, respectively. In addition, more than 49% of the surviving larvae in silks and grains completed the biological cycle. However, all life table parameters were negatively affected in insects that developed in silks and grains of both Bt corn events. In summary, the low biological activity of Bt proteins expressed on silks and grains of YieldGard VT PRO(tm) and PowerCore(tm) corn can contribute to the resistance evolution in S. frugiperda populations.

RESUMO: Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae ) é a principal praga-alvo dos eventos de milho YieldGard VT PRO(tm) (Cry1A.105/Cry2Ab2) e PowerCore(tm) (Cry1A.105/Cry2Ab2/Cry1F). Para subsidiar o manejo de resistência, avaliou-se a atividade biológica das proteínas de Bt expressas em diferentes estruturas dessas tecnologias de milho Bt contra S. frugiperda . Em discos de folha de milho YieldGard VT PRO(tm) e PowerCore(tm), houve mortalidade completa de neonatas de S. frugiperda . No entanto, em estilo-estigmas e grãos, a mortalidade foi inferior a 50% e 6%, respectivamente. Em adição, mais de 49% das larvas sobreviventes em estilos-estigmas e grãos completaram o ciclo biológico. No entanto, todos os parâmetros de tabela de vida de fertilidade foram negativamente afetados nos insetos que se desenvolveram em estilos-estigmas e grãos de milho Bt. A baixa atividade biológica das proteínas Bt expressas em estilos-estigmas e grãos de milho YieldGard VT PRO(tm) e PowerCore(tm) pode contribuir para a evolução de resistência em populações de S. frugiperda .

Bioecology of Spodoptera frugiperda (JE Smith, 1757) in different cover crops / Bioecologia de Spodoptera frugiperda (JE Smith, 1757) em diferentes plantas de cobertura

The objective of this work was to evaluate the biological variables of Spodoptera frugiperda on species of cover crops. The experiments were conducted in laboratory and greenhouse using the following species: sunflower (Helianthus annuus), sun hemp (Crotalaria juncea), brachiaria (Urochloa decumbens e Urochloa ruziziensis), millet (Pennisetum americanum), black oat (Avena stringosa), white lupin (Lupinus albus), forage turnip (Rafanus sativus) and maize (Zea mays). In laboratory the S. frugiperda larval survival varied from 57%, on L. albus, to 93% on H. annuus and the survival of the pre-imaginal phase varied from 45% on U. decumbens to 81.6% on Z. mays. On C. juncea the larval biomass was lower and the development period of the young and larval stage was higher. The adaptation index was less on C. juncea in greenhouse and laboratory. In greenhouse the larval survival at 14 days was similar for all plants and at 21 days was the lowest on C. juncea. There was less accumulation of biomass at 14 days on C. juncea and at 21 days on C. juncea and A. stringosa. Regarding damage, C. juncea presented less susceptibility to Spodoptera frugiperda attack, which together with the other evaluated parameters, indicated this plant as the most appropriate for soil cover before cultivation of maize.

O objetivo do trabalho foi avaliar variáveis biológicas de Spodoptera frugiperda (J.E. Smith, 1757) em espécies de plantas de cobertura. Os ensaios foram conduzidos em laboratório e casa de vegetação. Foram utilizadas as seguintes espécies: girassol (Helianthus annuus), crotalária (Crotalaria juncea), brachiaria (Urochloa decumbens e Urochloa ruziziensis), milheto (Pennisetum americanum), aveia preta (Avena stringosa), tremoço (Lupinus albus), nabo forrageiro (Rafanus sativus) e milho (Zea mays). Em laboratório, a sobrevivência larval de S. frugiperda variou de 57% em L. albus a 93% em H. annuus e a sobrevivência da fase pré-imaginal de 45% em U. decumbens a 81% no milho. Em C. juncea, a biomassa larval de S. frugiperda foi menor e o período de desenvolvimento da fase jovem e larval maior. O índice de adaptação foi menor em C. juncea em casa de vegetação e laboratório. Em casa de vegetação, a sobrevivência larval, aos 14 dias, foi similar em todas as plantas e, aos 21 dias, menor em C. juncea. Houve menor acúmulo de biomassa, aos 14 dias, em C. juncea e, aos 21 dias, em C. juncea e A. stringosa. Quanto à injúria, C. juncea apresentou menor susceptibilidade ao ataque de S. frugiperda. Os resultados indicam C. juncea como planta promissora para cobertura do solo antecedendo a cultura do milho.

Histological and histochemical changes by clove essential oil upon the gonads of Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae) / Alteraciones histológicas e histoquímicas provocadas por el aceite esencial de clavo de olor en las gónadas de Spodoptera frugiperda ( je smith ) (Lepidoptera: Noctuidae)

Spodoptera frugiperda is a polyphagous insect that causes economic losses to several crops in Brazil and is the major obstacle to corn production. Researches focusing on alternative control, e.g. botanical products are expanding to offer a wide variety of molecules that interfere with different biological parameters of insect pests. Thus, this study tested the hypothesis that clove essential oil affects the spermatogenesis, ovarioles histochemistry and the fertility of S. frugiperda. The results showed that clove essential oil affects the gametogenesis of S. frugiperda ovarioles, reflecting negatively on its reproduction, proving to be a promising tool for controlling this pest.

Spodoptera frugiperda es un insecto polífago que causa pérdidas económicas a varias cosechas en Brasil y es el mayor obstáculo para la producción de maíz. Este estudio está centrado en el control alternativo, con productos botánicos que se están expandiendo y ofrecen una amplia variedad de moléculas que interfieren con diferentes parámetros biológicos de plagas de insectos. Por tanto, se puso a prueba la hipótesis de que el aceite esencial de clavo de olor afecta la espermatogénesis. La histoquímica de los ovarioles y la fertilidad de S. frugiperda. Los resultados mostraron que el aceite esencial de clavo de olor afecta la gametogénesis de los ovarioles en S. frugiperda, lo que incide negativamente en su reproducción, demostrando ser una herramienta prometedora para el control de esta plaga.

First report of Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) on larvae of Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) in maize (Zea mays L.) under different cropping systems / Primeira ocorrência de Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) em larvas de Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) coletadas em milho (Zea mays L.) sob diferentes formas de cultivo

In the context of the modern agriculture, pest control is important in order to increase productivity in maize (Zea mays L.). However, this control should be done rationally, prioritising environmentally safer methods such as biological control. This paper aims to report the occurrence of Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) in Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) larvae collected in maize subjected to different cropping systems. The experiment was conducted at the Centro Nacional de Pesquisa de Milho e Sorgo (CNPMS) in Sete Lagoas, Minas Gerais State, Brazil, using organic and conventional production. Ten plants were sampled from each of the 24 plots and for each production system, three times a week during the entire cycle of maize (variety BR 106). In the laboratory, larvae were distributed in individual rearing containers with artificial diet until the end of the biological cycle. An increased number of S. frugiperda larvae was observed in organic single crop maize; hence a higher percentage of S. frugiperda larvae parasitised by Hymenoptera and Diptera also occurred in the maize under this production system. Dolichozele koebelei had not yet been described in association with larvae of S. frugiperda. The percentage of parasitism of S. frugiperda larvae was high in both experiments, indicating the importance of natural control agents in reducing the population density of S. frugiperda, and especially the importance of an appropriate crop management.

No contexto agrícola moderno, o controle de pragas é importante para se obter aumento de produtividade na cultura do milho (Zea mays L.). No entanto, esse controle deve ser feito racionalmente, e deve priorizar métodos ambientalmente mais seguros, como o controle biológico. Este trabalho teve como objetivo relatar a ocorrência de Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) em larvas de Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) coletadas em milho sob diferentes formas de cultivo. O experimento foi conduzido no Centro Nacional de Pesquisa de Milho e Sorgo (CNPMS) em Sete Lagoas, Minas Gerais, Brasil, em áreas de produção orgânica e convencional. Durante todo o ciclo do milho (cultivar BR 106), três vezes por semana, foram amostradas em cada uma das 24 parcelas, 10 plantas, que foram avaliadas no laboratório. As larvas encontradas foram distribuídas individualmente em recipientes de criação com dieta artificial até o final do ciclo biológico. Maior número de larvas de S. frugiperda foi obtido no milho orgânico solteiro, com maior percentual de larvas de S. frugiperda parasitadas por Hymenoptera ou Diptera. Dolichozele koebelei ainda não havia sido descrita em associação com larvas de S. frugiperda. De uma forma geral nos dois experimentos o percentual de larvas de S. frugiperda parasitadas, foi alto, indicando a importância dos agentes de controle natural na redução da densidade populacional de S. frugiperda e, principalmente, a importância do manejo adequado da cultura do milho.

First report of Dolichozele koebeleiViereck, 1911 (Hymenoptera: Braconidae) on larvae of Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) in maize (Zea maysL.) under different cropping systems

In the context of the modern agriculture, pest control is important in order to increase productivity in maize (Zea maysL.). However, this control should be done rationally, prioritising environmentally safer methods such as biological control. This paper aims to report the occurrence of Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) in Spodoptera frugiperda(J. E. Smith, 1797) (Lepidoptera: Noctuidae) larvae collected in maize subjected to different cropping systems. The experiment was conducted at the Centro Nacional de Pesquisa de Milho e Sorgo (CNPMS) in Sete Lagoas, Minas Gerais State, Brazil, using organic and conventional production. Ten plants were sampled from each of the 24 plots and for each production system, three times a week during the entire cycle of maize (variety BR 106). In the laboratory, larvae were distributed in individual rearing containers with artificial diet until the end of the biological cycle. An increased number of S. frugiperda larvae was observed in organic single crop maize; hence a higher percentage of S. frugiperda larvae parasitised by Hymenoptera and Diptera also occurred in the maize under this production system. Dolichozele koebelei had not yet been described in association with larvae of S. frugiperda. The percentage of parasitism of S. frugiperda larvae was high in both experiments, indicating the importance of natural control agents in reducing the population density of S. frugiperda, and especially the importance of an appropriate crop management.

No contexto agrícola moderno, o controle de pragas é importante para se obter aumento de produtividade na cultura do milho (Zea mays L.). No entanto, esse controle deve ser feito racionalmente, e deve priorizar métodos ambientalmente mais seguros, como o controle biológico. Este trabalho teve como objetivo relatar a ocorrência de Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) em larvas de Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) coletadas em milho sob diferentes formas de cultivo. O experimento foi conduzido no Centro Nacional de Pesquisa de Milho e Sorgo (CNPMS) em Sete Lagoas, Minas Gerais, Brasil, em áreas de produção orgânica e convencional. Durante todo o ciclo do milho (cultivar BR 106), três vezes por semana, foram amostradas em cada uma das 24 parcelas, 10 plantas, que foram avaliadas no laboratório. As larvas encontradas foram distribuídas individualmente em recipientes de criação com dieta artificial até o final do ciclo biológico. Maior número de larvas de S. frugiperda foi obtido no milho orgânico solteiro, com maior percentual de larvas de S. frugiperda parasitadas por Hymenoptera ou Diptera. Dolichozele koebelei ainda não havia sido descrita em associação com larvas de S. frugiperda. De uma forma geral nos dois experimentos o percentual de larvas de S. frugiperda parasitadas, foi alto, indicando a importância dos agentes de controle natural na redução da densidade populacional de S. frugiperda e, principalmente, a importância do manejo adequado da cultura do milho.

Euplectrus furnius parasitizing Spodoptera frugiperda in maize in Brazil / Euplectrus furnius parasitando Spodoptera frugiperda em milho no Brasil

Brazil is among the world's biggest maize producers and fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), is the main insect pest on this crop in the country. Despite the importance of its natural enemies, there still is a lack of information about parasitoids species that attack this insect-pest, such as larval parasitoids. This research reports Euplectrus furnius Walker (Hymenoptera: Eulophidae) parasitizing S. fugiperda larvae on maize crop in Brazil.

O Brasil está entre os maiores produtores de milho do mundo e a lagarta-do-cartucho, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) é o principal inseto-praga nessa cultura no país. Apesar da importância de seus inimigos naturais, ainda existe uma falta de informação sobre as espécies de parasitoides que atacam esse inseto-praga, tais como os parasitoides larvais. Este trabalho relata Euplectrus furnius Walker (Hymenoptera: Eulophidae) parasitando larvas de S. frugiperda em milho no Brasil.

New method for rearing Spodoptera frugiperda in laboratory shows that larval cannibalism is not obligatory

New method for rearing Spodoptera frugiperda in laboratory shows that larval cannibalism is not obligatory. Here we show, for the first time, that larvae of the fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera, Noctuidae), can be successfully reared in a cohort-based manner with virtually no cannibalism. FAW larvae were reared since the second instar to pupation in rectangular plastic containers containing 40 individuals with a surprisingly ca. 90% larval survivorship. Adult females from the cohort-based method showed fecundity similar to that already reported on literature for larvae reared individually, and fertility higher than 99%, with the advantage of combining economy of time, space and material resources. These findings suggest that the factors affecting cannibalism of FAW larvae in laboratory rearings need to be reevaluated, whilst the new technique also show potential to increase the efficiency of both small and mass FAW rearings.

Behavior of transgenic maize hybrids and their conventional isogenic counterparts in relation to infestation of spodoptera frugiperda (J. E. Smith, 1727) (lepidoptera: noctuidae) at two locations and sowing dates / Comportamento de híbridos de milho transgênicos e respectivos híbridos isogênicos convencionais em relação à infestação de Spodoptera Frugiperda (j. E. Smith,1727) (Lepidoptera: Noctuidae) em duas localidades e épocas de semeadura

The fall armyworm Spodoptera frugiperda is one of the most important pests of maize. Various studies are conducted for their management, integrating chemical and biological control tactics as well as resistant plants. In order to offer alternatives for an efficient management of this pest with minimal use of pesticides, the technology of genetically modified plants resistant to insects has been widely studied. The aim of the present study was to evaluate the natural infestation of larvae of S. frugiperda and their injuries under field conditions in transgenic maize hybrids compared to their conventional isogenic counterparts at two sowing dates and two regions. The hybrids were planted in the "off season" of 2010 in Jaboticabal, SP, Brazil, and the summer of 2010/2011 in Jaboticabal, and Pindorama, SP, in a randomized block with seven treatments (hybrids) and four replications. Different levels of infestation of larvae occurred throughout the phenological development of plants in conventional and genetically modified hybrids with significant differences between the two groups in most evaluations. The hybrid 2B710HX was the least infested with caterpillars and had the least damaged leaf area. It follows that the Cry1F toxin was the most effective in protecting the plant in relation to other toxic proteins expressed by the other Bt hybrids against infestation and damage promoted.

A lagarta-do-cartucho, Spodoptera frugiperda, é uma das mais importantes pragas do milho. Vários estudos são realizados para o seu manejo, integrando táticas de controle químico, biológico ou através de plantas resistentes. No intuito de oferecer alternativas a um manejo eficiente dessa praga com a mínima utilização de agrotóxicos, a tecnologia das plantas geneticamente modificadas resistentes a insetos tem sido objeto de muitos estudos. Neste trabalho, o objetivo foi avaliar a infestação natural de lagartas de S. frugiperda e respectivas injúrias em condições de campo, em híbridos transgênicos de milho comparados aos seus isogenes convencionais, em duas épocas de semeadura e em duas regiões. Os híbridos foram semeados na "safrinha" de 2010 em Jaboticabal, SP, e no verão em 2010/2011, em Jaboticabal, e Pindorama, SP, em delineamento de blocos ao acaso, com sete tratamentos (híbridos) e quatro repetições. Diferentes níveis de infestação de lagartas ocorreram durante todo o desenvolvimento fenológico das plantas nos híbridos convencionais e nos híbridos geneticamente modificados, com significativas diferenças entre os dois grupos na maioria das avaliações. O híbrido 2B710HX foi o menos infestado com lagartas e o com menor área foliar danificada, o que se conclui que a toxina Cry1F foi a mais efetiva na proteção da planta em relação às demais proteínas.