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Emphasis has been given in the Brazilian state of Mato Grosso to the implementation of more sustainable production practices, including what has been termed agrosilvopastoral production system (ASPS), which involves the integration of different types of land use in a same area along time, seeking increased ecological stability. The Gamasina mite group (order Mesostigmata) is usually diverse and abundant in non-cultivated soils, where they can prey on arthropods and nematodes; some are commercialized for biological pest control. The objective of this study was to evaluate the diversity and abundance of edaphic Gamasina in plots of grain production managed under conventional (alternating cultivation) system and under ASPS, both with the adoption of no-tillage cultivation, in the municipality of Sinop, Mato Grosso state. In samples of soil and litter taken biweekly from August 2015 to May 2016, 762 Gamasina representing 32 species of 21 genera and nine families were collected. Considering both systems together, the dominant Gamasina were quite different from those of other parts of Brazil. Calculated ecological indexes showed no major differences between the two systems, possibly because of the relatively short time since the implementation of ASPS. In both systems, Rhodacaridae was one of the dominant families (37.5% of the Gamasina), followed by Macrochelidae (20.9%) and Laelapidae (18.8%). The most abundant species were Multidentirhodacarus squamosus Karg (Rhodacaridae), a new species of Holostaspella (Macrochelidae) and Cosmolaelaps barbatus Moreira, Klompen and Moraes (Laelapidae). Future studies are warranted, allowing more time for the adoption of ASPS to produce possible ecological changes.

Among the primary beef producers globally, Brazil stands out due to livestock production based on pastures without massive grain dependence. Moreover, the adoption of integrated systems has increased in Brazilian farms in the past few years, reaching significant numbers such as 11.5 million hectares covered by some sort of integration, including silvopastoral systems (SPS). This study aimed to evaluate the diversity of Coleoptera species and dung pats decomposition in an open pasture (OP) of Urochloa brizantha cv. Marandu and in an SPS with Eucalyptus urograndis clone H13. There were no significant differences in dung beetle richness or abundance in OP and SPS, as well as similar rates of dung pats disintegration. Most insects were captured during the rainy season, and richness and diversity of species were similar between systems. The traps' distance to the Eucalyptus rows did not influence the number of dung beetles sampled; however, fewer individuals were captured under the tree rows. We suggest the importance of beetles for cattle dung decomposition and biological control of parasites, eventhough community structure was similar between systems with different habitat complexity.

Fall armyworm (FAW), Spodoptera frugiperda, is one of the most destructive pests of maize in warm regions of the Americas and a severe invasive species in Africa. Considering the armyworm management and its ability to develop resistance rapidly to synthetic insecticides and Bacillus thuringiensis (Bt) toxins, we assessed the response of field and laboratory populations of FAW to Bt maize hybrids and Bt-based bioinsecticides. In the laboratory, FAW neonates from two Bt-resistant colonies and three field-collected populations were fed foliage of Bt maize or Bt bioinsecticides incorporated into artificial diet, and larval survival and biomass were recorded after seven days. Larvae of the two laboratory colonies resistant to Bt maize producing Cry1 or Cry2 toxins had high larval survival rates on foliage of specific Bt maize hybrids (i.e., Cry1F or Cry1A.105 + Cry2Ab). On foliage of the Cry1A.105 + Cry2Ab Bt maize, larvae of one of the field-collected populations had survival rates similar to the Bt-resistant laboratory larvae but had strong growth inhibition. The field-collected larvae had less than 30% survival on foliage of Cry1F maize and larval weights equivalent to those of the Cry1F-resistant colony. In addition, while some larvae survived exposure to formulations of B. thuringiensis kurstaki (i.e., Dipel and Thuricide), the two formulations of B. thuringiensis aizawai (i.e., Agree and Xentari) caused 100% larval mortality in all FAW colonies and the field populations, including the ones showing reduced-susceptibility to Cry1F or Cry1A.105 + Cry2Ab Bt maize. This research shows that there are field populations of FAW with different levels of susceptibility to specific Bt toxins and that resistance to Cry1 and/or Cry2 may or may not reduce the efficacy of certain Bt bioinsecticides against the neonates.

The aim of this work was to evaluate the influence of production systems involving the eucalyptus culture on infestation as well as the necessity of controlling its defoliator Glena unipennaria in order to qualify how sustainable integrated production systems are. Adult infestation was evaluated in the following systems: (1) eucalyptus monoculture, (2) agroforestry (grains integrated with eucalyptus), (3) silvopastoral (palisade grass integrated with eucalyptus) and (4) agrosilvopastoral (palisade grass cultivated after grains, both integrated with eucalyptus) production systems. Results showed that adult infestations in integrated systems are significantly lower and different from eucalyptus in monoculture. Consequently, the defoliation rate by caterpillars occurred mainly in monoculture, with greater intensity in the interior of the plot compared to the trees in the edge, suggesting that solar irradiance influences the pest establishment in the field. Besides that, in eucalyptus monoculture, it was necessary to use two sprays of Bacillus thuringiensis-based insecticides at 1 L ha−1 with a 15-day interval, while in the integrated systems this was not needed due to the low damage caused.

EN-US: Due to the reduced host spectrum of the entomopathogenic fungus Metarhizium rileyi, its pathogenicity against different target insects must be assessed to develop biopesticides capable of controlling more than one pest species. This study aimed to evaluate the susceptibility of the pest species Chrysodeixis includens and Spodoptera frugiperda to different isolates of M. rileyi and, thus, determine a possible influence of the host of origin on the pathogenic activity of these isolates. Three isolates [CG1312 (C. includens as original host), CG381 (S. frugiperda as original host) and a new wild isolate (C. includens as original host)] were tested against larvae of C. includens and S. frugiperda, in third instar age, by treatment of surfaces with conidial suspension, under laboratory conditions. Both species were susceptible to the isolates of M. rileyi, with mortality rates of 53-58 % for C. includens and 74-84 % for S. frugiperda. The results suggest that the host of origin may not be determinant in the selection of pathogenic isolates of M. rileyi against these two pest insects. | PT-BR: Em razão do reduzido espectro hospedeiro do fungo entomopatogênico Metarhizium rileyi, sua patogenicidade contra diferentes insetos alvos deve ser avaliada para o desenvolvimento de bioinseticidas capazes de controlar mais de uma espéciepraga. Objetivou-se avaliar a suscetibilidade das espécies-pragas Chrysodeixis includens e Spodoptera frugiperda a diferentes isolados de M. rileyi e, assim, determinar uma possível influência do hospedeiro de origem na atividade patogênica desses isolados. Três isolados [CG1312 (C. includens como hospedeiro original), CG381 (S. frugiperda como hospedeiro original) e um novo isolado selvagem (C. includens como hospedeiro original)] foram testados contra lagartas de C. includens e S. frugiperda, em idade de terceiro instar, por tratamento de superfícies com suspensão de conídios, em laboratório. Ambas as espécies foram suscetíveis aos isolados de M. rileyi, com índices de mortalidade de 53-58 % para C. includens e 74-84 % para S. frugiperda. Os resultados sugerem que o hospedeiro de origem pode não ser determinante na seleção de isolados patogênicos de M. rileyi contra essas duas espécies de praga. Made available in DSpace on 2021-02-25T15:38:57Z (GMT). No. of bitstreams: 1 2020-cpamt-rmp-susceptibility-spodoptera-frungiperda-infections-caused-metarhizium.pdf: 246715 bytes, checksum: b2ad28e5f5f5c574f27dcd58cb5fa5da (MD5) Previous issue date: 2020

The efficacy of the fungus Metarhizium rileyi (Farlow) Kepler, S. A. Rehner & Humber (Hypocreales: Clavicipitaceae) against the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) and the impact on the community of epigeans predators as well as the natural occurrence of native fungal strains were evaluated after sequential sprays in maize. In the first season, the infestation was lower than 0.2 larvae per plant throughout the three fungal sprays and no significant difference was observed in the number of infected larvae among treatments. In the second season, insect population reached an average of 0.8 larvae per plant between the second and third sprays and the number of larvae succumbed by M. rileyi was higher in fungal-treated plots in the following weeks. Molecular characterization of the collected isolates on mummified larvae revealed the introduction of a new isolate did not eliminate the native strain on the fungal-treated plots. In both seasons, the diversity and abundance of predator species in the plots were not affected by any of the treatments. We showed that applications of selected strains of M. rileyi early in the season have no significant impact on the occurrence of natural enemies in maize.

The soybean looper (Chrysodeixis includens) is an important defoliation pest in crops such as soybean and cotton in Brazil. Its main control tactic is chemical insecticides. Considering the importance of chemical control for this pest, monitoring the susceptibility of C. includens populations is strategic for an efficient Insect Resistance Management. Therefore, the objective of this study was to evaluate the susceptibility levels of C. includens populations in the state of Mato Grosso - Brazil to lufenuron and spinosad. Seven populations were collected in soybean fields around the state. For the bioassays, early L3 larvae were exposed to insecticides using the diet-overlay method. Although the compounds have distinct modes of action, Tangará da Serra population had the highest resistance ratios for lufenuron (11.62) and spinosad (7.84), compared to laboratory population (susceptibility reference). Even with low resistance levels, it is necessary to maintain regional monitoring of C. includens susceptibility to the evaluated insecticides, as well as to extend the range of molecules monitored.

Emamectin Benzoate was registered recently in Brazil to control Chrysodeixis includens (Walker, [1858]) (Lepidoptera: Noctuidae) in soybean. We studied the baseline susceptibility of Mato Grosso populations of C. includes to support Insect Resistance Management programs by standard feeding assays on insecticide-surface of artificial diet. Variation in susceptibility between populations was low. The LC50 values from 11 populations varied between 0.015 a 0.065 µg i.a. cm-2. Based on our results, we propose the discriminant concentration of 2.867 µg i.a. cm-2 of emamectin benzoate to monitor insecticide resistance in C. includes.

EFEITO DE DENSIDADES DE Chrysodeixis includens (LEPIDOPTERA, NOCTUIDAE) NA PRODUTIVIDADE DO ALGODOEIRO A existencia de plantios de soja proximos aos de algodao tem favorecido a migracao de especies de lepidopteros-praga entre essas culturas, como a falsa-medideira, Chrysodeixis includens, praga desfolhadora da soja, mas que esta atacando o algodoeiro. O objetivo deste trabalho foi identificar qual a densidade de lagartas de C. includens que causa reducao na produtividade do algodoeiro. O delineamento foi em blocos ao acaso com seis tratamentos (0, 2, 4, 6, 8 e 16 lagartas.metro-1) e cinco repeticoes. As plantas da cultivar FM 944GL, no estadio F2, foram infestadas com lagartas em terceiro instar, protegidas por gaiola de PVC (1,0 m x 1,0 m x 1,6 m (C x L x H)) revestida com organza. Os dados de producao e desfolha foram submetidos a analise de variância pelo teste F e analise de regressao. De acordo com os resultados constatou-se que a presenca de duas lagartas.m-1, de terceiro instar, de C. includens nao afetou a produtividade do algodoeiro na fase F2; e a partir de quatro lagartas.m-1 de terceiro instar houve reducao na produtividade do algodoeiro. Nos tratamentos com duas, quatro, seis, oito e dezesseis lagartas a desfolha foi de 4%, 10%, 6%, 13% e 24%, respectivamente.Palavras-chave: Gossypium hirsutum; falsa-medideira; herbivoria; manejo. ABSTRACT: The cultivation of soybean near to cotton areas has favored the migration of lepidopteran pests between those crops, including the soybean looper, Chrysodeixis includens, which usually attacks soybean leaves but can also attack cotton plants. The objective of this study is to identify the density of C. includens larvae capable of decreasing cotton productivity. Six treatments (0, 2, 4, 6, 8 and 16 larvae.meter-1) with five replications were arranged in a completely randomized block design. Plants of cultivar FM 944GL at stage F2 were protected by PVC cages (length, 1.0 m; width, 1.0 m, height, 1.6 m) covered with organza fabric and infested with third-instar larvae. Crop yield and defoliation data were subjected to analysis of variance using the F-test and regression analysis. The results indicated that the presence of two third-instar larvae.m-1 did not affect cotton yield in the F2 phase whereas four or more third-instar larvae.m-1 decreased cotton yield. The rate of defoliation was 4%, 10%, 6%, 13%, and 24% in the treatments with two, four, six, eight, and sixteen larvae, respectively.Keywords: Gossypium hirsutum; soybean looper; herbivory; management.

The aim of this study was to identify resistance of tolerance type in Citrus and Poncirus genotypes towards the citrus leafminer (CLM), Phyllocnistis citrella. The quantitative variables leaf and shoot lengths, leaf width, number of larvae and new shoots, and fresh and dry shoots weights, and qualitative variables associated with foliar damage were evaluated in six Citrus-related genotypes infested with CLM. In preliminary trials with lime Rough lemon (C. jambhiri), the variables that best discriminated the infestation effect of CLM were established as the numbers of larvae and new shoots per plant together with the percentages of partially rolled leaves (PRL), rolled leaves (RL) and total damage (TD = RL + PRL). In subsequent tests with all six genotypes, the variables new shoots per plant, percentage of attacked but not rolled leaves (ANRL), RL and TD were found to be significant. Trifoliata Limeira (P. trifoliata) and hybrid C × R4 (C. sunki × P. trifoliata) presented the lowest percentages of RL and TD and the highest values of ANRL. A cluster analysis was performed considering all the variables analyzed and the most tolerant genotypes for CLM, namely hybridsC × R4, C × R315 (C. sunki × P. trifoliata), M × P222 [C. sinensis × Tangor Murcott (C. reticulata × C. sinensis)] and Trifoliata Limeira (P. trifoliata) were grouped apart from the less tolerant genotypes Sunki mandarin (C. sunki) and lime Rough lemon. In conclusion, genotypes Trifoliata Limeira and its hybrid C × R4 are the most tolerant to CLM.

Diversified systems allow the balance of the ecosystem, reducing the action of harmful insects to monoculture by retention time and immigration of the natural enemies. The objective of this research was to monitor the population of psilids, hemiptera, Psylloidea: Aphalaridae, deeucaliptos in integrated production systems. The evaluations were carried out in an experiment on productive systems integrating the components of eucalyptus crop, pasture and forest in a transition region between Cerrado and Amazonia in the State of Mato Grosso, Brazil. The study was conducted from June 2013 to September 2014, with assessments conducted during periods of drought and rain. The eggs, nymphs and adults of Spondyliaspidinae were quantified in each production system, using as methods of collection, adhesive traps and collection of the eucalyptus branches. The species Glycaspisbrimblecombei and Blastopsyllaoccidentalis were found. The largest infestations of eggs, nymphs and adults were in the dry period. The treatments did not differ for the variable eggs of B. occidentalis, but presented a significant difference for nymphs and adults. The effect of the treatments was not significant for eggs, nymphs and adults of G. brimblecombei. The time did not show a significant difference for the eggs of G. brimblecombei, but significant for their nymphs and adults. It concludes that the psyllids were not harmful to eucalyptus in the studied silvicultural phase and that the diverse landscape contributes to the reduction

Helicoverpa armigera (Hübner) is part of an important complex of insects-pests that attack the cotton crop. This study aimed to identify the preferential plant parts for the oviposition of moths, as well as the movement and feeding behavior of caterpillars, in the vegetative phase of the cotton cultivar BRS 369 RF. Plants emitting floral buds were used to study the oviposition behavior of moths. For this, a completely randomized design, with three treatments (adaxial and abaxial sides of the leaf and floral buds) and twenty replications (plants in pots), was used. In order to evaluate the behavior of the caterpillars in the cotton vegetative phase, another 3 × 5 factorial design, with nine replications, was used. The treatments were three ages (first, second and third instars) combined with five behaviors (walking, resting, waving, eating and drop-off). In this trial, the period of the day when caterpillars are more active was also evaluated. It was observed that H. armigera moths prefer to lay their eggs on the adaxial leaf side and on the last two nodes of the plant, in a descending direction. The adaxial leaf side is also the part of the plant preferred by caterpillars for walking, eating and resting, being this last behavior the most frequent in all instars. In general, the caterpillars walk more in the morning. RESUMO Helicoverpa armigera (Hübner) faz parte de um importante complexo de insetos-pragas que atacam a cultura do algodoeiro. Objetivou-se identificar partes da planta preferenciais para a oviposição das mariposas, bem como os comportamentos de movimentação e alimentação das lagartas, na fase vegetativa da cultivar de algodão BRS 369 RF. Plantas emitindo botões florais foram utilizadas para estudar o comportamento de oviposição das mariposas. Para isso, utilizou-se delineamento inteiramente casualizado, com três tratamentos (faces adaxial e abaxial da folha e botões florais) e vinte repetições (plantas em vasos). Para avaliar o comportamento das lagartas na fase vegetativa do algodoeiro, adotou-se outro delineamento fatorial 3 × 5, com nove repetições. Os tratamentos foram três idades (1º, 2º e 3º ínstares) combinadas com cinco comportamentos (caminhar, repousar, acenar, comer e cair). Neste ensaio, o período do dia em que as lagartas são mais ativas também foi avaliado. Constatou-se que as mariposas de H. armigera preferem ovipositar na face adaxial da folha e nos dois últimos nós da planta, em direção descendente. A face adaxial da folha também é a parte da planta preferida pelas lagartas para caminhar, comer e repousar, sendo este último comportamento o mais frequente em todos os ínstares. Em geral, as lagartas caminham mais no período matutino.

Resumo: O objetivo deste trabalho foi avaliar o índice de adaptação e o tempo letal de populações da lagarta-do-cartucho [Spodoptera frugiperda (Lepidoptera: Noctuidae)] em milho Bt que expressa as proteínas Cry1Ab, Cry1F, Cry1A.105/Cry2Ab2 e Vip3Aa20. Três bioensaios foram conduzidos com lagartas coletadas em Inhaúma, MG, e em Sinop, MT. As lagartas dessas populações foram alimentadas com folhas de milho não Bt e Bt. As seguintes variáveis foram avaliadas: sobrevivência larval, biomassa de pupas e período de desenvolvimento larval. Em seguida, foram calculados os índices de adaptação e o tempo letal dessas populações. Para a análise do tempo letal, também foram utilizados dados de mortalidade de uma população obtida de milho Bt Cry1F em Piumhi, MG. O milho Bt Cry1Ab apresentou eficiência limitada, mas duradoura. Já os milhos Bt Cry1A.105/Cry2Ab2 e Vip3Aa20 reduziram o desempenho de S. frugiperda, respectivamente, a menos de 5 e 0%, independentemente da origem da colônia. A população originada de Sinop apresentou alto desempenho larval no milho Bt Cry1F, o que mostra sua resistência a essa proteína e certo nível de custo adaptativo. O tempo letal pode ser uma variável indicadora de evolução de resistência, pois é maior para as populações com maior adaptação. Abstract: The objective of this work was to evaluate the fitness index and lethal time of fall armyworm [Spodoptera frugiperda (Lepidoptera: Noctuidae)] populations on Bt corn expressing the Cry1Ab, Cry1F, Cry1A.105/Cry2Ab2, and Vip3Aa20 proteins. Three bioassays were conducted with larvae collected at the municipality of Inhaúma, in the state of Minas Gerais, and at the municipality of Sinop, in the state of Mato Grosso, Brazil. Larvae from these populations were fed with leaves of non-Bt and Bt corn. The following variables were evaluated: larval survival, pupae mass, and larval development period. Then, the fitness indexes and lethal time of these populations were calculated. For lethal time analysis, mortality data of a population collected from Cry1F Bt corn in the municipality of Piumhi, in the state of Minas Gerais, were also used. The Cry1Ab Bt corn showed a limited but durable efficiency. The Cry1A.105/Cry2Ab2 and Vip3Aa20 Bt corn reduced S. frugiperda performance, respectively, to less than 5 and 0%, regardless of the origin of the colony. The population from Sinop showed high larval performance in Cry1F Bt corn, showing its resistance to this protein and a certain level of fitness cost. The lethal time can be a variable that indicates evolution of resistance, since it is greater for populations with greater fitness.

A nanotecnologia, atraves do encapsulamento de ingredientes ativos, tem-se revelado uma importante estrategia para evitar problemas com a rapida degradacao de moleculas inseticidas. Assim, nanoformulacoes a base de oleo de nim ( Azadirachta indica ) utilizando os polimeros ?-ciclodextrina e poli-?-caprolactona (PCL) foram testadas quanto a sua eficiencia de controle de ovos e ninfas de Bemisia tabaci (Genn.) biotipo B mantidas em soja. Foi estimada a CL 50 utilizando uma formulacao comecial de oleo de nim (Organic Neem ® ) sobre ninfas em 1o instar da qual se estipulou o volume das nanoformulacoes a serem utilizadas por tratamento. Depois disso, os tratamentos foram aplicados sobre ovos e ninfas de 1o instar em laboratorio e em casa de vegetacao e sobre ninfas de 3o instar em casa de vegetacao. O oleo comercial e agua destilada foram utilizados como controles. A viabilidade dos ovos nao foi afetada por qualquer dos tratamentos. Das seis formulacoes testadas, somente uma delas mostrou-se eficiente para ninfas de 1o instar em condicoes de laboratorio, embora nao tenha apresentado aumento do periodo residual como esperado. Em casa de vegetacao, ninfas de 1o instar foram mais afetadas por duas das formulacoes, que diferenciaram do oleo de nim que causou maior controle. No teste com ninfas de 3o instar, nao houve diferenciacao de mortalidade entre as formulacoes. As nanoformulacoes foram menos eficientes para controlar ninfas de B. tabaci biotipo B do que o oleo de nim comercial.

The development and reproduction of the citrus leafminer (CLM), Phyllocnistis citrella Stainton, were evaluated in six citrus genotypes in order to identify genotypes with resistance traits that could be applied in a program for the development of citrus varieties resistant to the citrus leafminer. Tests were conducted under controlled laboratory conditions (25 ± 1ºC, 70 ± 10% RH, and 14h photophase). Seedlings of each genotype tested were infested with eggs obtained from a stock colony of CLM maintained on 'Cravo' lemon (Citrus limonia L. Osbeck), and the duration and survival of the eggs, larval and pupal stages, pupal size and weight, fecundity and longevity of adults, and sex ratio were evaluated. No influence was observed on the duration and survival of eggs, larvae and pupae of P. citrella. However, pupae obtained in the hybrid C x R(4) were significantly smaller and lighter than pupae from the remaining treatments. Adult females from the hybrids C x R(4) and C x R(315) were the least fecund. However, the lowest value for the corrected reproductive potential (CRP) was recorded in the hybrid C x R(315), suggesting that this genotype is the least favorable for the development and reproduction of CLM. On the other hand, the highest CRP value obtained in the 'Rugoso' lemon confirms the susceptibility of this genotype, indicating it as the most suitable for CLM.

The influence of Urochloa brizantha (variety Marandu) grazing systems on Mahanarva spectabilis (Distant) and the entomopathogen Metarhizium anisopliae (Metsch.) was studied to understand the benefits of integrated systems in pest management. The pastoral systems studied were: (M) monoculture, (SP) silvopastoral and (ICLF). We assessed the number, per square meter, of alive spittlebug nymphs or infected by M. anisopliae as well as the demanded number of entomopathogen sprays in each pasture system to control the pest. Throughout the experiment period, M. spectabilis was the unique species found. Silvopastoral had a higher number of alive nymphs and a lower percentage of the infected nymphs compared to pasture in monoculture; however, in both systems, only one spray of M. anisopliae was enough to keep the pest below its threshold. In agrosilvopastoral system, there was no spittlebugs infestation, consequently, none sprays was demanded. Thus, intensified production systems such ICLF may be more sustainable, considering pest aspects. Made available in DSpace on 2020-02-06T18:09:14Z (GMT). No. of bitstreams: 1 2019cpamtrafaelpittainfluencepastoralmahanarvaspectabilisentomopathogenmetarhiziumsorokin.pdf: 362586 bytes, checksum: 30350d57b6d05e096106cdfe12033dbd (MD5) Previous issue date: 2019