Academic literature on the topic 'Armyworms Biological control'

Fall armyworm [Spodoptera frugiperda (J. E. Smith, 1797)] was first reported in the Americas, then spread to all the continents of the world. Chemical insecticides are frequently employed in managing fall armyworms. These insecticides have various modes of actions and target sites to kill the insects. Chlorantraniliprole is a selective insecticide with a novel mode of action and is used against Lepidopteran, Coleopteran, Isopteran, and Dipteran pests. This study determined chlorantraniliprole's lethal, sub-lethal, and trans-generational effects on two consecutive generations (F0, F1, and F2) of the fall armyworm. Bioassays revealed that chlorantraniliprole exhibited higher toxicity against fall armyworms with a LC50 of 2.781 mg/l after 48 h of exposure. Significant differences were noted in the biological parameters of fall armyworms in all generations. Sub-lethal concentrations of chlorantraniliprole showed prolonged larval and adult durations. The parameters related to the fitness cost in F0 and F1 generations showed non-significant differences. In contrast, the F2 generation showed lower fecundity at lethal (71 eggs/female) and sub-lethal (94 eggs/female) doses of chlorantraniliprole compared to the control (127.5–129.3 eggs/female). Age-stage specific survival rate (Sxj), life expectancy (Exj) and reproductive rate (Vxj) significantly differed among insecticide-treated groups in all generations compared to the control. A comparison of treated and untreated insects over generations indicated substantial differences in demographic parameters such as net reproduction rate (R0), intrinsic rate of increase (r), and mean generation time (T). Several biological and demographic parameters were shown to be negatively impacted by chlorantraniliprole. We conclude that chlorantraniliprole may be utilized to manage fall armyworms with lesser risks.

The Australian grains industry is dealing with a shifting complex of invertebrate pests due to evolving management practices and climate change as indicated by an assessment of pest reports over the last 20–30 years. A comparison of pest outbreak reports from the early 1980s to 2006–07 from south-eastern Australia highlights a decrease in the importance of pea weevils and armyworms, while the lucerne flea, Balaustium mites, blue oat mites and Bryobia mites have increased in prominence. In Western Australia, where detailed outbreak records are available from the mid 1990s, the relative incidence of armyworms, aphids and vegetable weevils has recently decreased, while the incidence of pasture cockchafers, Balaustium mites, blue oat mites, redlegged earth mites, the lucerne flea and snails has increased. These changes are the result of several possible drivers. Patterns of pesticide use, farm management responses and changing cropping patterns are likely to have contributed to these shifts. Drier conditions, exacerbated by climate change, have potentially reduced the build-up of migratory species from inland Australia and increased the adoption rate of minimum and no-tillage systems in order to retain soil moisture. The latter has been accompanied by increased pesticide use, accelerating selection pressures for resistance. Other control options will become available once there is an understanding of interactions between pests and beneficial species within a landscape context and a wider choice of ‘softer’ chemicals. Future climate change will directly and indirectly influence pest distributions and outbreaks as well as the potential effectiveness of endemic natural enemies. Genetically modified crops provide new options for control but also present challenges as new pest species are likely to emerge.

Abstract Peppers were transplanted on 10 Sep 25 cm apart in 2 rows 12.5 cm to either side of the centerline in plastic-mulched, raised beds on sand soil with seep irrigation. Treatments were replicated 4 times in a randomized complete block design with each treatment plot consisting of 6 m of double-row bed. One week prior to treatment, a single neonate BAW was placed on the center 12 plants in each plot. Treatments were applied with a drop nozzle sprayer using a diaphragm pump driven by a dedicated engine and pulled with an all terracum vehicle. Albuz yellow tip ceramic nozzles delivering 0.45 gpm at the operation pressure of 100 psi were used on a single-row boom. Sprayer configuration was adjusted for adequate coverage, beginning on 10 Oct with 2 over-the-row and 2 side nozzles for the first through fourth application, and adding 2 additional side nozzles with a single overhead for the remaining 3 applications. Delivery rates were 30 gal/acre for the first application, 50 gal/acre for the second through the fourth, and 63 gal/acre for the rest. The surfactant APSA-80 (@0.03%) was added to all 16 treatments and the water control. The NPV formulation, SX-61991, was applied by backpack sprayer because of windy conditions on the second and third application dates, to reduce the risk of cross-plot contamination. Five randomly selected plants from each plot were examined for armyworms 2 days post-treatment. The top 5 leaves of 2 or more growing tips of each of the same plants were evaluated for worm damage. Twenty plants near the center of each plot were randomly selected on 20 Nov and 11 Dec for harvest and evaluation. Pressure was intense during most of the trial with SAW the predominant species. The most significant differences were between chemical and biological treatments. Differences between Bt treatments were less evident, although dose responses were generally consistent for all products.

The strawberry crop endures economic losses due to feeding injury from a number of phytophagous arthropod pests. A number of invasive pests have posed challenges to crop protection techniques in the strawberry cropping system recently. It is increasingly evident that sole reliance on chemical control options is not sustainable. In this review, current challenges and advances in integrated pest management of various strawberry pests are presented. Key pests discussed include thrips, mites, lygus bug, spotted wing drosophila, seed bug, weevils, aphids, whiteflies, and armyworms. Several integrated pest management techniques that include use of intercropping, resistant cultivars, irradiation with gamma rays, use of spectral sensitivity of pests, biological control agents and natural enemies, and biorational pesticides have recently been reported to be useful in managing the various strawberry pests. With the increase in world production of strawberry, several techniques will be necessary to manage the pest complex of strawberry.

Background The cultivation of Bt maize (maize genetically modified with Bacillus thuringiensis) continues to expand globally. Arbuscular mycorrhizal fungi (AMF), an important kind of microorganism closely related to soil fertility and plant nutrition, may influence the ecological risk of target lepidopteran pests in Bt crops. Methods In this study, transgenic Bt maize (Line IE09S034 with Cry1Ie vs. its parental line of non-Bt maize cv. Xianyu335) was inoculated with a species of AMF, Glomus caledonium (GC). Its effects on the food utilization, reproduction and development of armyworm, Mythimna separata, were studied in a potted experiment from 2017 to 2018. Results GC inoculation increased the AMF colonization of both modified and non-modified maize, and also increased the grain weight per plant and 1,000-grain weight of modified and non-modified maize. However, the cultivation of Bt maize did not significantly affect the AMF colonization. The feeding of M. separata with Bt maize resulted in a notable decrease in RCR (relative consumption rate), RGR (relative growth rate), AD (approximate digestibility), ECD (efficiency of conversion of digested food) and ECI (efficiency of conversion of ingested food) parameters in comparison to those observed in larvae fed with non-Bt maize in 2017 and 2018, regardless of GC inoculation. Furthermore, remarkable prolongation of larval life span and decreases in the rate of pupation, weight of pupa, rate of eclosion, fecundity and adult longevity of M. separata were observed in the Bt treatment regardless of GC inoculation during the two-year experiment. Also, when M. separata was fed with Bt maize, a significant prolongation of larval life and significant decreases in the pupal weight, fecundity and adult longevity of M. separata were observed when inoculated with GC. However, it was just the opposite for larvae fed with non-Bt maize that was inoculated with GC. The increased percentage of larval life-span, the decreased percentages of the food utilization, and the other indexes of reproduction, growth, and development of M. separata fed on Bt maize relative to non-Bt maize were all visibly lower when under GC inoculation in contrast to the CK. Discussion It is presumed that Bt maize has a marked adverse impact on M. separata development, reproduction and feeding, especially when in combination with the GC inoculation. Additionally, GC inoculation favors the effectiveness of Bt maize against M. separata larvae by reducing their food utilization ability, which negatively affects the development and reproduction of the armyworm. Thus, Bt maize inoculated with AMF (here, GC) can reduce the severe threats arising of armyworms, and hence the AMF inoculation may play an important ecological functions in the field of Bt maize ecosystem, with potentially high control efficiency for the target lepidopteran pests.

The fall armyworm (FAW), Spodoptera frugiperda, is one of the most important invasive pests worldwide, resulting in considerable losses in host crops. FAW comprises two genetic strains, such as the “rice strain”, which prefers rice and other grass species, and the “maize strain”, which feeds upon maize and sorghum. Potential control measures are generally more applicable to the farmers who lack financial assets to buy chemical insecticides or costly pure seeds. The adverse effects of pesticides on the ecosystem and human’s health and the development of resistance to insect pests have exaggerated efforts to find an alternative strategy that is cost-effective, low-risk and target-specific. Therefore, biological control is widely considered as one of the most important options for insect pest management. This comprehensive review amasses the information on biological control in all phases of their development, including predators, parasitoids, entomopathogenic fungi, viruses, nematodes, bacteria, and biopesticides, with a special focus on their effectiveness against FAW. The findings regarding biological control are briefly discussed in light of improving management programs of the invasive pest S. frugiperda.

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a maize pest worldwide. Its host range comprises more than 350 reported plant species, and it is the primary insect pest attacking maize in Florida. Global trade has not only assisted but accelerated its invasion into the Eastern Hemisphere. Regular pesticide use promotes resistance in the species; therefore, there is an urgent need for alternative pest management strategies. This study evaluated the interactions of biological control agents within a similar guild. Some of the reported interactions could potentially lead to the integration of these agents within the same niche to increase biological control efficiency against the fall armyworm. We evaluated three biocontrol agents that are natural enemies of Lepidopteran pests, the true bugs Podisus maculiventris and Euthyrhynchus floridanus (Hemiptera: Pentatomidae) and a parasitoid, Cotesia marginiventris (Hymenoptera: Braconidae). Depending on their intraguild interactions, these agents could potentially be useful for biological control of the fall armyworm. The study investigated these three biocontrol agents and concluded that integrating these agents to control the fall armyworm is a possibility; however, only under certain conditions. Investigations were focused on evaluating the predator–parasitoid and devised pairing interactions. Predator response to prey in a choice or no-choice scenario and choices based on olfaction or other bodily cues were studied under experimental laboratory conditions.

AbstractMicroplitis mediator (Haliday) is being considered for introduction into Saskatchewan to augment the biological control of the bertha armyworm, Mamestra configurata Walker. It was reared in the laboratory on larvae of the bertha armyworm. Notes on the life history and descriptions of the egg and three larval stages are given.

<abstract><p>In this study, we present a non-autonomous model with a Holling type II functional response, to study the complex dynamics for fall armyworm-maize biomass interacting in a periodic environment. Understanding how seasonal variations affect fall armyworm-maize dynamics is critical since maize is one of the most important cereals globally. Firstly, we study the dynamical behaviours of the basic model; that is, we investigate positive invariance, boundedness, permanence, global stability and non-persistence. We then extended the model to incorporate time dependent controls. We investigate the impact of reducing fall armyworm egg and larvae population, at minimal cost, through traditional methods and use of chemical insecticides. We noted that seasonal variations play a significant role on the patterns for all fall armyworm populations (egg, larvae, pupae and moth). We also noted that in all scenarios, the optimal control can greatly reduce the sizes of fall armyworm populations and in some scenarios, total elimination may be attained. The modeling approach presented here provides a framework for designing effective control strategies to manage the fall armyworm during outbreaks.</p></abstract>

A field study was conducted at Yuma in 1990 to examine the efficacy of several biological insecticide formulations on beet armyworm in seedling lettuce. After a single application at thinning, none of the insecticides adequately reduced larval populations below damaging levels. Reductions in plant stand by larvalfeeding were significantly lower in plots treated with Lannate, Javelin, Biobit and Dipel. Lettuce seedling densities were reduced greaterthan 80% in untreated plots.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Bacillus thuringiensis é entomopatogênica muito utilizada no controle de insetos-praga e a predição de sua atividade tóxica é realizada por PCR na identificação de genes cry. Assim sendo, este trabalho objetivou elaborar novos oligonucleotídeos iniciadores para a detecção das subclasses cry1Ab, cry1Ac, cry1Ca, cry1Ea e cry1Fa, estudar o potencial de controle de 31 isolados de B. thuringiensis à duas populações de Spodoptera frugiperda por meio de bioensaios e analisar a taxa de expressão dos genes presentes nos isolados por qPCR em tempo real. Um par de oligonucleotídeo iniciador foi elaborado para cada subclasse e dentre os isolados testados 6,5% e 48,5% apresentaram os genes cry1Ab e cry1Ac, respectivamente, nenhum dos isolados apresentou os genes cry1Ca, cry1Ea e cry1Fa. Dentre os 31 isolados, 13 apresentaram mortalidade acima de 75% para as larvas da população de campo e apenas nove para a população de laboratório, mostrando que os isolados controlaram com maior eficiência as larvas da população de campo. A presença dos genes cry1Ab e cry1Ac conjuntamente foi associada à elevado potencial de controle às larvas da população de campo e baixo às larvas da população de laboratório. A expressão do gene cry1Ab, não foi constatada em nenhum dos isolados nas condições analisadas e, para o gene cry1Ac, todos os isolados apresentaram taxa de expressão. Os resultados de expressão foram associados ao potencial de controle das larvas de S. frugiperda das populações testadas, sendo que os elevados níveis de expressão do gene cry1Ac foram associados diretamente a elevado potencial de controle da população de laboratório.
Bacillus thuringiensis is entomopathogenic used for insect control and the prediction of the toxic activity is performed by PCR on the identification of cry genes. Thus, the aim of this research was develop news primers for detection the subclasses cry1Ab, cry1Ac, cry1Ca, cry1Ea and cry1Fa, study the potential control of 31 isolates of B. thuringiensis against two Spodoptera frugiperda populations by bioassays and analyze the rate of gene expression present on the isolates by real-time qPCR. A pair of primer was prepared for each subclass, the genes cry1Ab and cry1Ac were found in 6.5% and 48.5% of the isolates, respectively, and the genes cry1Ca, cry1Ea and cry1Fa were not detected on the isolates. Among the 31 isolates, 13 showed over 75% mortality for the larvae of field population and only nine isolates to the laboratory population, showing that the isolates controlled more efficiently the larvae of the field population. The presence of cry1Ab and cry1Ac genes were correlated to high levels of insecticidal activity for the larvae of field population and low levels control to the laboratory population. The expression of cry1Ab was not found in any of the isolates analyzed and the rates expression of cry1Ac gene was detected in all isolates. The results of gene expression were associated with the potential control to S. frugiperda, and the high levels of cry1Ac gene expression were linked directly to high levels of insecticidal activity for the laboratory population.

Resumo: Bacillus thuringiensis é entomopatogênica muito utilizada no controle de insetos-praga e a predição de sua atividade tóxica é realizada por PCR na identificação de genes cry. Assim sendo, este trabalho objetivou elaborar novos oligonucleotídeos iniciadores para a detecção das subclasses cry1Ab, cry1Ac, cry1Ca, cry1Ea e cry1Fa, estudar o potencial de controle de 31 isolados de B. thuringiensis à duas populações de Spodoptera frugiperda por meio de bioensaios e analisar a taxa de expressão dos genes presentes nos isolados por qPCR em tempo real. Um par de oligonucleotídeo iniciador foi elaborado para cada subclasse e dentre os isolados testados 6,5% e 48,5% apresentaram os genes cry1Ab e cry1Ac, respectivamente, nenhum dos isolados apresentou os genes cry1Ca, cry1Ea e cry1Fa. Dentre os 31 isolados, 13 apresentaram mortalidade acima de 75% para as larvas da população de campo e apenas nove para a população de laboratório, mostrando que os isolados controlaram com maior eficiência as larvas da população de campo. A presença dos genes cry1Ab e cry1Ac conjuntamente foi associada à elevado potencial de controle às larvas da população de campo e baixo às larvas da população de laboratório. A expressão do gene cry1Ab, não foi constatada em nenhum dos isolados nas condições analisadas e, para o gene cry1Ac, todos os isolados apresentaram taxa de expressão. Os resultados de expressão foram associados ao potencial de controle das larvas de S. frugiperda das populações testadas, sendo que os elevados níveis de expressão do gene cry1Ac foram associados diretamente a elevado potencial de controle da população de laboratório.
Abstract: Bacillus thuringiensis is entomopathogenic used for insect control and the prediction of the toxic activity is performed by PCR on the identification of cry genes. Thus, the aim of this research was develop news primers for detection the subclasses cry1Ab, cry1Ac, cry1Ca, cry1Ea and cry1Fa, study the potential control of 31 isolates of B. thuringiensis against two Spodoptera frugiperda populations by bioassays and analyze the rate of gene expression present on the isolates by real-time qPCR. A pair of primer was prepared for each subclass, the genes cry1Ab and cry1Ac were found in 6.5% and 48.5% of the isolates, respectively, and the genes cry1Ca, cry1Ea and cry1Fa were not detected on the isolates. Among the 31 isolates, 13 showed over 75% mortality for the larvae of field population and only nine isolates to the laboratory population, showing that the isolates controlled more efficiently the larvae of the field population. The presence of cry1Ab and cry1Ac genes were correlated to high levels of insecticidal activity for the larvae of field population and low levels control to the laboratory population. The expression of cry1Ab was not found in any of the isolates analyzed and the rates expression of cry1Ac gene was detected in all isolates. The results of gene expression were associated with the potential control to S. frugiperda, and the high levels of cry1Ac gene expression were linked directly to high levels of insecticidal activity for the laboratory population.
Orientador: Manoel Victor Franco Lemos
Coorientador: Odair Aparecido Fernandes
Banca: Jackson Antônio Marcondes de Souza
Banca: Celso Omoto
Mestre

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Outra
Este estudo teve como objetivos determinar a capacidade de dispersão do parasitoide Telenomus remus Nixon (Hymenoptera: Platygastridae) e armazenamento do hospedeiro visando o controle de Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) na cultura de milho. Estabeleceram-se doze parcelas de 829,44 m2. Cada parcela continha quatro quadrados concêntricos cuja distância desde o centro até o ponto médio de cada lado foi de 3,6; 7,2; 10,8 e 14,4 m, marcando-se em cada quadrado 8, 16, 24 e 32 pontos (plantas). As plantas foram infestadas artificialmente com massas de ovos de S. frugiperda. A infestação foi realizada com uma massa de ovos/planta em 1,6% das plantas na parcela. Após isso, foram liberados 100.000, 150.000 e 200.000 parasitoides/ha em plantas de milho nos estádios fenológicos V4-V5 e V8-V9. Houve ainda um tratamento no qual não houve liberação de parasitoides. As massas de ovos foram recolhidas após 48 h e levadas para laboratório para avaliação de parasitismo. Adotou-se o delineamento experimental de blocos ao acaso com três repetições. Foi determinado o porcentual de parasitismo em cada ponto onde houve infestação. Avaliou-se também, a influência de diferentes temperaturas (5, 10, 15, 20°C) e períodos de armazenamento (0, 3, 6, 9, 12 e 15 dias) no parasitismo de T. remus em ovos de S. frugiperda. Após esses períodos foram colocadas fêmeas do parasitoide e mantidas em sala climatizada (25±1°C, UR de 70±10% e fotofase de 12 horas) para posterior avaliação do porcentual de parasitismo. O estádio fenológico do milho influenciou na dispersão de T. remus, sendo a distância média percorrida de 11,4 m no estádio fenológico V4-V5 e 9,8 m no V8-V9. Não houve diferença significativa entre as densidades de parasitoides liberadas. Assim, sugere-se a liberação de 100.000 parasitoides distribuídos em 68 pontos/ha no estádio fenológico V4-V5 do milho e 91 no estádio V8-V9. Em relação ao armazenamento de ovos, houve diferença significativa entre as temperaturas e períodos de armazenamento avaliados. Portanto, o armazenamento de ovos do hospedeiro pode ser realizado até nove dias a 15°C.
The objective of this study was to know the dispersal capacity of the parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae) and host storage for the control of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) in maize. Twelve plots of 829.44 m2 each were established. Each plot contained four concentric squares whose distance from the center to the midpoint of each side was 3.6; 7.2; 10.8 and 14.4 m, being each square with 8, 16, 24 and 32 sampling points (plants). The plants were artificially infested with egg masses of S. frugiperda. The infestation was performed using one egg mass /plant in 1.6% of the plants in a plot. After that, 100,000, 150,000 and 200,000 parasitoids/ha were released in maize at the V4-V5 and V8-V9 phenological stages. There was also a treatment in which there was no release of parasitoids. The egg masses were collected after 48 h and taken to the laboratory for parasitism evaluation. A randomized complete block design with three replicates was used. The percentage of parasitism was determined at each point where infestation occurred. The influence of different temperatures (5, 10, 15, 20 °C) and storage periods (0, 3, 6, 9, 12 and 15 days) was also evaluated on T. remus parasitism in S. frugiperda eggs. After these periods, egg masses were offered to parasitoid female for oviposition and kept in an acclimatized room (25±1°C, RH 70±10% and photo phase of 12 hours). The phenological stage of maize influenced the dispersal of T. remus, with a mean distance of 11.4 m and 9.8 m in the in the V4-V5 and V8-V9 phenological stages, respectively. There was no significant difference between the densities of released parasitoids. Thus, we suggest the release of 100,000 parasitoids distributed in 68 points/ha in the V4-V5 phenological stage of maize and 91 in the V8-V9 stage. Regarding egg storage, there was a significant difference among the temperatures and storage periods evaluated. Therefore, storage of the host can be carried out up to nine days at 15 °C.
Resolución Jefatural No. 251-2015-MINEDU-VMGI-PRONABEC-OBPOST

A partir de 24 amostras de solos foram isoladas 461 colônias bacterianas, sendo que destas 190 foram identificadas como Bacillus thuringiensis (Bt). A relação entre as características químicas das amostras de solos e a presença do patógeno pode ser expressa por iBt = -0,4 + 0,6Ca + 0,07Cu + 0,009Fe - 0,53Mg -0,12Mn + 1,26Zn. Dentre os 83 isolados de Bt testados para o controle de Spodoptera frugiperda, o ESALQ 3.7 mostrou-se mais promissor para o controle desta praga, causando 86,6% de mortalidade em lagartas provenientes da população de São Paulo, com uma CL50 estimada de 0,749 x 108 esporos/mL. Esse isolado possui as toxinas Cry1Ac, Cry1C e Cry1E que justificam sua eficiência para S. frugiperda. Toxinas da classe Cry1 foram encontradas em 72% dos isolados testados contra este inseto. Foram observadas diferenças na suscetibilidade entre as três populações (São Paulo, Minas Gerais e Rio Grande do Sul) da lagarta-do-cartucho do milho para 49,4% dos isolados testados e na população de São Paulo, alguns isolados afetaram os parâmetros biológicos das lagartas sobreviventes aos tratamentos. A persistência do Dipel foi superior às outras formulações de Bt, até 27 horas depois da aplicação dos tratamentos (65.772 esporos/mL), porém sua meia vida (p = 17,54 horas) foi inferior ao Ecotech e Bac-Control. O estudo da persistência do isolado ESALQ 3.7 foi prejudicado por fatores bióticos e abióticos tanto em campo como em casa-de-vegetação, que comprometeram a validação dos resultados. Não foi verificada diferença estatística significativa nas notas da escala de dano causado pela lagarta-do-cartucho na testemunha e o tratamento com o isolado ESALQ 3.7. Nos estudos de interação com outros entomopatógenos observou-se que entre Bt e Heterorhabditis sp. ocorreu interação positiva, variando de efeito aditivo a sinergismo subaditivo, de acordo com a concentração do nematóide. Entre Bt e os fungos entomopatogênicos Beauveria bassiana e Nomuraea rileyi foi verificada interação negativa (antagonismo) e entre um vírus de poliedrose nuclear e Bt a interação foi negativa e positiva (efeito aditivo), dependendo da concentração do vírus.
From 24 soil samples about 461 bacterial colonies have been isolated, and 190 were identified as Bacillus thuringiensis (Bt). The relation between soil chemical characteristics and the presence of this pathogen may be expressed by the equation iBt = -0,4 + 0,6Ca + 0,07Cu + 0,009Fe - 0,53Mg -0,12Mn + 1,26Zn. Among 83 Bt isolates assayed against Spodoptera frugiperda, the ESALQ 3.7 was the most effective to control this pest, causing 86.6% of mortality to São Paulo larvae, with an estimated LC 50 of 0.749 x 108 spores/mL. This isolate has the toxins Cry1Ac, Cry1C e Cry1E that justify its efficiency against S. frugiperda. The Cry1 toxins were found in 72% of isolates assayed for this pest. There have been observed differences in the susceptibility among three fall armyworm populations (São Paulo, Minas Gerais e Rio Grande do Sul) to 49.4% of the assayed isolates, and some of them affected the biological parameters of the São Paulo larvae. The Dipel persistence was higher than the others Bt based products, until 27 hours after application (65.772 spores/mL), but its half life (p = 17.54 hours) was lower than Ecothech and Bac-Control. The study of ESALQ 3.7 persistence was prejudiced by biotic and abiotic factors in field condition and at the greenhouse conditions, that consequently constrained the data validation. About the isolate ESALQ 3.7 efficiency in the field, there was no statistical differences in the damage caused by fall armyworm in the control and treatment. In the interaction studies with other entomopathogens, it was observed a positive interaction between Bt and Heterorhabditis sp. This interaction varied from na additive effect to a subadditive sinergism, according to nematode concentration. Between Bt and entomopathogenic fungi Beauveria bassiana e Nomuraea rileyi it was observed a negative interaction (antagonism). Also, the interaction between a poliedrosis nuclear vírus and Bt varied according to the virus concentration.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O presente trabalho teve como objetivos estudar os tipos de resistência de cultivares de algodoeiro sobre Spodoptera frugiperda (J.E. Smith, 1797) e Alabama argillacea (Hubner, 1818) (Lepidoptera: Noctuidae) e efeito na biologia de Podisus nigrispinus (Dallas, 1851) (Hemiptera: Pentatomidae) alimentados com S. frugiperda. Os experimentos foram conduzidos no Departamento de Fitossanidade da Faculdade de Ciências Agrárias e Veterinárias, Câmpus de Jaboticabal/SP, sendo os testes realizados no Laboratório de Resistência de Plantas a Insetos, sob condições ambientais controladas (temperatura: 27±2 ºC, 70±10% de U.R. e fotofase de 12 horas). Nos experimentos para avaliar a resistência de algodoeiro (Gossypium hirsutum L.), utilizou-se as cultivares DeltaOpal, NuOpal, FMX 993, FMT 701, FMX 910 e FMX 996 para S. frugiperda, enquanto que para A. argillacea as cultivares DeltaOpal, NuOpal, FMT 701, FMX 910 e FMX 996. Foi avaliada a não-preferência para oviposição e alimentação em teste com chance de escolha, adotando-se o delineamento estatístico em blocos casualizados e no teste sem chance para oviposição e alimentação o inteiramente casualizado. Para avaliar a antibiose, folhas das mesmas cultivares foram fornecidas as larvas de S. frugiperda e A. argillacea diariamente, verificando-se a duração de cada fase do inseto, avaliando-se a massa de larvas aos dez dias de idade, massa de pupas com 24 horas, período larval e pupal, longevidade de adultos, viabilidade total e fecundidade. No estudo da influência de cultivares de algodoeiro sobre a biologia de P. nigrispinus em relação à presa S. frugiperda, foram utilizados as cultivares DeltaOpal, NuOpal, FMX 910 e FMX 996. Para o teste de atratividade, utilizou-se um olfatômetro o qual constou de quatro compartimentos, no interior dos quais se colocou uma lagarta de S. frugiperda com 15 dias de idade alimentada com as...
This work aimed to study the resistance of cotton cultivars on Spodoptera frugiperda (JE Smith, 1797) and Alabama argillacea (Hubner, 1818) (Lepidoptera: Noctuidae) on the biology of Podisus nigrispinus (Dallas, 1851) (Hemiptera: Pentatomidae) fed with S. frugiperda. The experiments were conducted at the Departamento de Fitossanidade da Faculdade de Ciências Agrárias e Veterinárias, Câmpus de Jaboticabal/SP, and the tests were carried out at the Laboratório de Resistência de Plantas a Insetos, under controlled conditions (temperature: 27 ± 2 º C, 70 ± 10 % RH and photophase of 12 hours). In experiments to evaluate the cotton resistance (Gossypium hirsutum L.) was used the cultivars DeltaOpal, NuOpal, FMX 993, FMT 701, FMX 910 and FMX 996 to S. frugiperda, while to A. argillacea were used the cultivars DeltaOpal, NuOpal, FMT 701, FMX 910 and FMX 996. The non-preference for oviposition and feeding was evaluated in test-choice, adopting the randomized block design, and testing without chance for oviposition and feeding completely randomized. To assess the antibiosis, leaves of those cultivars were provided larvae of A. argillacea and S. frugiperda, daily, checking for the duration of each insect stage, evaluating the mass of larvae to ten days old, mass of pupae at 24 hours, larval and pupal stages, adult longevity, total survival and fecundity. In the study influence of cotton cultivars on the behavior and biology of P. nigrispinus in relation to prey S. frugiperda, were used the cultivars DeltaOpal, NuOpal, FMX 910 and FMX 996. For the attractive test used an olfactometer, which consisted of four compartments, inside which stood a larvae S. frugiperda 15 days of age fed cultivars, then released in the middle of this, 12 adults of the predator. This procedure consisted of 5 repetitions, adopting the randomized block design, evaluating the number of insects attracted to the cavity ... (Complete abstract click electronic access below)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Fall armyworm, Spodoptera frugiperda (J.E. Smith), is considered the major pest of corn. In general, the control of larvae is achieved with insecticides application, which can cause several environmental problems. In search of alternative control methods, egg parasitoids of the genus Trichogramma have been used in applied biological control programs, since they are aggressive in the host search. Therefore, the objective of this study was to evaluate aspects related with S. frugiperda control efficiency, in field corn, through Trichogramma pretiosum. Experiments were made in two periods: in 2006/2007 at 10º District Arroio Grande, Santa Maria, RS, and in 2007/2008, in two growth seasons, at Pinheirinho, Santa Bárbara do Sul, RS, where three situations were compared: one area was maintained only with S. frugiperda natural control, other with about 110 thousand T. pretiosum release per hectare, and a third with chemical control application, with 150 mL/ha of Rimon® 100 EC (novarulon) and 60 mL/ha Lannate® BR (metomil); each area with 30 x 30 m. The experimental design was randomized blocks with sampling in the plots. Each period and growth season were considered one repetition, therefore comprising three repetitions. All areas were divided in 16 plots, where the evaluations were made. Six plants per plot were sampled randomly and evaluated, and the plants were examined for: the presence or absence of S. frugiperda egg masses, the egg masses location at the plant and on the surface of the leaf, and the presence or absence of damage caused by the fall armyworm. The evaluations were performed daily, reducing the frequency as the presence of egg masses decreased. On each date, the phenological stage of plants was checked and, daily, reported the air temperature and rainfall. At the end of the crop cycle, the yield was assessed. The collected egg masses were taken to the Laboratory of Entomology, Department of Plant Protection, CCR/UFSM, where they were packed in gelatin capsules, and subsequently analyzed for the hatching of larvae or the emergence of parasitoids. The emerged male parasitoids were identified. As main results, it is possible to point out: S. frugiperda preferred to oviposit in the median part of the plant and the abaxial surface of the leaf and, preferentially, in the early stages (V1-V8) of the crop; natural parasitism of S. frugiperda eggs by richogramatids was low; in RS, S. frugiperda eggs can be parasitized by T. pretiosum, Trichogramma atopovirilia, Trichogramma rojasi and Trichogrammatoidea sp., with predominance of the first two (around 70 and 30% of identified parasitoids, respectively); T. rojasi and, possibly, Trichogrammatoidea sp. had the first record of occurrence in S. frugiperda eggs; plants without damages caused by fall armyworm predominate until the V5 stage, and with more severe damage (perforated leaf) from V6 to V10; the chemical control, with metomil (Lannate® BR) and novaluron (Rimon® 100 EC), does not interfere in the number of eggs or egg masses of S. frugiperda as well as in the parasitoids population; and one release of T. pretiosum does not result in increase in the rate of parasitized eggs and the yield of corn crop.
A lagarta-do-cartucho, Spodoptera frugiperda (J. E. Smith), é considerada a principal praga da cultura do milho. O controle das lagartas é realizado através da aplicação de inseticidas, que podem provocar vários problemas ambientais. Na busca de métodos alternativos de controle, parasitóides de ovos do gênero Trichogramma vêm sendo utilizados em programas de controle biológico aplicado, por serem agressivos na procura pelo hospedeiro. Assim, o objetivo deste trabalho foi avaliar aspectos relacionados à eficiência de controle de S. frugiperda, na cultura do milho, com Trichogramma pretiosum. Os ensaios foram realizados em duas safras: 2006/2007, no 10º Distrito Arroio Grande, Santa Maria, RS e 2007/2008, em duas épocas, em Pinheirinho, Santa Bárbara do Sul, RS, onde foram comparadas três situações: uma área foi mantida apenas com controle natural de S. frugiperda, outra com liberação de cerca de 110 mil T. pretiosum por hectare e, uma terceira, com aplicação de controle químico com 150 mL/ha de Rimon® 100 EC (novarulon) e 60 mL/ha Lannate® BR (metomil), sendo cada área com 30 x 30 m. O delineamento experimental utilizado foi de blocos ao acaso com amostragens nas parcelas. Cada safra e época foram consideradas uma repetição, totalizando, portanto, três repetições. Todas as áreas foram divididas em 16 parcelas cada uma, onde foram realizadas as avaliações. Foram amostradas ao acaso e avaliadas seis plantas/parcela, sendo que as plantas eram examinadas quanto: à presença ou não de posturas de S. frugiperda, à localização das posturas na planta e na superfície da folha, e à presença ou não de danos causados pela lagarta-do-cartucho. As avaliações foram realizadas diariamente, diminuindo a periodicidade conforme diminuía a presença de posturas. Em cada data, foi verificado o estádio fenológico das plantas e, diariamente, registradas a temperatura do ar e a precipitação pluviométrica. Ao final do cultivo, foi avaliado o rendimento. As posturas coletadas foram conduzidas ao Laboratório de Entomologia do Departamento de Defesa Fitossanitária, CCR/UFSM, onde foram acondicionadas em cápsulas gelatinosas para remédio e, posteriormente, analisadas quanto à eclosão de lagartas ou à emergência de parasitóides. Os parasitóides machos emergidos foram identificados. Como resultados principais, pode-se destacar que: S. frugiperda apresentou preferência em ovipositar na região mediana da planta e na superfície abaxial da folha e, preferencialmente, em estádios iniciais (V1-V8) da cultura; o parasitismo natural em ovos de S. frugiperda por tricogramatídeos foi baixo; no RS, os ovos de S. frugiperda podem ser parasitados por T. pretiosum, Trichogramma atopovirilia, Trichogramma rojasi e Trichogrammatoidea sp., com predomínio dos dois primeiros (cerca de 70% e 30% dos parasitóides identificados, respectivamente); T. rojasi e, possivelmente, Trichogrammatoidea sp. tiveram o primeiro registro de ocorrência em ovos de S. frugiperda no presente trabalho; plantas sem danos causados pela lagarta-do-cartucho predominam até o estádio V5 e, com danos mais severos (folha perfurada), de V6 a V10; o controle químico não interfere tanto no número de ovos e de posturas S. frugiperda quanto na população de parasitóides; e uma liberação inundativa de T. pretiosum não resulta em acréscimo no índice de ovos parasitados nem no rendimento da cultura de milho.

Orientador: Maria Lígia Rodrigues Macedo
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Inibidores de peptidases (IPs) são proteínas vegetais envolvidas nos mecanismos de defesa contra herbívoros e patógenos. São considerados agentes antimetabólicos, uma vez que sua presença na dieta de insetos compromete seu desenvolvimento normal. Este efeito se dá através da formação de complexos entre os IPs e as enzimas digestivas, comprometendo assim o processo digestivo dos insetos. Neste trabalho, investigamos efeitos do inibidor de tripsina de sementes de Adenanthera pavonina (ApTI) sobre o desenvolvimento de dois insetos-praga, a broca-da-cana (Diatraea saccharalis) e a lagarta-do-cartucho (Spodoptera frugiperda). Bioensaios, estudos bioquímicos e de proteômica, foram realizados a fim de determinar o efeito de ApTI sobre o desenvolvimento destes insetos. A exposição aguda de larvas de D. saccharalis ao ApTI diminuiu a atividade das tripsinas e quimotripsinas em 87% e 63%, respectivamente. ApTI afetou o desenvolvimento deste inseto como observado através da diminuição na viabilidade larval (55%) e pupal (20,6%). Larvas oriundas da geração F1 apresentaram efeitos similares aos observados na geração F0, como redução no peso (23%) e na taxa de sobrevivência (33%). Análises bioquímicas revelaram que o inibidor foi refratário à digestão pelas peptidases de D. saccharalis e que o perfil de enzimas digestivas permaneceu sensível à inibição por quantidades crescentes de ApTI. Entretanto, não foi possível realizar a identificação das proteínas do intestino desta lagarta por espectrometria de massas. Larvas de S. frugiperda foram criadas em dieta contendo 0,5% de ApTI. Ao final dos experimentos, uma redução no peso médio larval de 30% foi observada. Porém, diferentemente dos resultados obtidos para D. saccharalis, as enzimas das larvas alimentadas com ApTI mostraram-se resistentes à inibição, sugerindo que esta espécie adapta-se à dieta contendo inibidor. O sequenciamento das proteínas presentes nos fluidos intestinais de S. frugiperda permitiu a identificação de 41 proteínas. Dentre elas foi possível identificar serinopeptidases do tipo tripsina e quimotripsina, proteínas estruturais, enzimas quinases e fosfatases. Nossos resultados demonstram que são necessários novos estudos para obtenção de mais informações acerca das proteínas presentes no fluido intestinal de S. frugiperda, para correlacionarmos sua expressão diferencial em larvas submetidas a diferentes tratamentos, conhecendo desta maneira um novo indício sobre os mecanismos adaptativos desta espécie contra os IPs
Abstract: Peptidase inhibitors (PIs) are plant proteins involved in defense mechanisms against herbivores and pathogens. They are considered antinutritional compounds, since their presence in insect diet hinder the normal larval development. This effect is due the complexation between PIs and peptidases, affecting the insect digestive process. In this work, we investigated the effects of trypsin inhibitor from Adenanthera pavonina seeds (ApTI) on the development of two pest insects: the sugarcane borer (Diatraea saccharalis) and the fall armyworm (Spodoptera frugiperda). Biochemical and proteomic studies were carried out in order to determine the ApTI effects on the development of these insects. The acute exposure of sugarcane borer to ApTI reduced the trypsin and chymotrypsin activities in 87% and 63%, respectively. The effect of ApTI on development of sugarcane borer was noticed by reduced larval (23%) and pupal viability (33%). Biochemical analysis revealed that the inhibitor was refractory to digestion by D. saccharalis peptidases and the enzymes maintained sensibility to inhibition by increasing amounts of ApTI. However, it was not possible to identify proteins from sugarcane borer gut through mass spectrometry approach. S. frugiperda larvae were reared in artificial diet containing 0.5% ApTI and a reduction in average larval weight of 30% was noticed. But, differently of D. saccharalis, S. frugiperda midgut enzymes became resistant to inhibition by ApTI, showing that this species adapted to ApTI-diet. From the sequencing of S. frugiperda gut fluid proteins we identified 41 proteins. Among them, we identified trypsin and chymotrypsin enzymes, structural proteins and quinases and phosphatases enzymes. Our results demonstrated that further researches are necessary in order to obtain more information about proteins from S. frugiperda gut fluid. The correlation between differential expressed proteins in larvae submitted to different treatments is crucial to reach new indicatives about the adaptive mechanisms this species evolve against PIs
Doutorado
Bioquimica
Doutora em Biologia Funcional e Molecular

Armyworm (Spodoptera frugiperda) is a pest on several food crops including soybeans and corn. Armyworm control still emphasizes the use of resistant varieties and insecticides. Alternative efforts are needed to use more environmentally-friendly control methods, including the use of organic pesticides from biological materials. The control of Spodoptera frugiperda was carried out by testing the application of several types of organic pesticides at the same concentration of 50%. The purpose of this study was to determine the type of pesticide that was most effective in reducing mortality and attack from Spodoptera frugiperda. The study was started by doing mass propagation of S. frugiperda larvae, S. frugiperda larvae investment, and mortality test. The test used the Randomized Block Design (RBD) method using several organic pesticides consisting of five treatments, namely P0 (control), P1 (tobacco), P2 (shallot), P3 (garlic), and P4 (papaya leaves), P5 (blimbing wuluh leaves), P6 (Jatropa curcas fruit), P7 (lemongrass). The results of the application of organic pesticides on the mortality and attack rate of S. frugiperda had a significant effect. Organic pesticides that are most effective in reducing the mortality and attack rates of S. frugiperda are pesticides made from tobacco (Nicotiana tabacum). At a concentration of 50% organic pesticides made from tobacco can reduce the mortality of S. frugiperda up to 100%. Tobacco-based pesticides also received the lowest land attack rate at 46%. Organic pesticides applied to S. frugiperda larvae also affect the growth of S. frugiperda pupae.