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Tuta absoluta, known as the South American tomato leaf miner, significantly impacts tomato plants (Solanum lycopersicum) economically on a global scale. This pest, belonging to the Gelechiidae family, is native to South America and was first identified in Peru in 1917. Since its discovery, T. absoluta has rapidly spread to Europe, Africa, and Asia, severely threatening tomato production in these regions. The widespread application of chemical pesticides against this pest has resulted in significant environmental harm, including contamination of soil and water, and has had negative effects on non-target species such as beneficial insects, birds, and aquatic life. Although substantial research has been conducted, biological control methods for T. absoluta remain insufficient, necessitating further study. This review covers the Biology, Classification, and Entomopathogen-Based Management of T. absoluta (Meyrick) in Asia. It provides essential insights into the pest's life cycle, ecological impacts, and the potential of entomopathogens as biocontrol agents. The detailed information presented aims to facilitate the development of sustainable pest control strategies, minimizing environmental impact and promoting the use of entomopathogens as viable alternatives to chemical pesticides in controlling T. absoluta insect pest.

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As an alternative to chemical insecticides, gut bacteria of insects could be used to control insect pests. In this study, bacteria associated with Tuta absoluta, an invasive species that has developed resistance to chemical insecticides, were isolated, and their potential for pest control was investigated. We isolated 13 bacteria from larvae of the pest and identified the isolates on the basis of their morphological, physiological, biochemical, and molecular characteristics as Bacillus thuringiensis (Ta1-8), Staphylococcus petrasii (Ta9), Citrobacter freundii (Ta10), Chishuiella changwenlii (Ta11), Enterococcus casseliflavus (Ta12), and Pseudomonas tremae (Ta13). A laboratory screening test at 109 cfu/ml showed that B. thuringiensis (Bt) isolates caused more than 90% mortality after 3 days. Among the isolates, Bt-Ta1 showed the highest mortality in a short time. The LC50 and LC90 values for Bt-Ta1 were estimated to be 1.2 × 106 and 2 × 109 cfu/ml, respectively. Detailed characterization of Bt-Ta1 revealed that it is one of the serotypes effective on lepidopterans and contains the genes cry1Aa, cry2Aa, and vip3Aa, which encode lepidopteran toxic proteins. Bt-Ta1 isolate has been shown to have the potential to be used in the integrated management of Tuta absoluta.

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The invasive tomato leaf miner, Phthorimaea absoluta, is conventionally controlled through chemical insecticides. However, the rise of insecticide resistance has necessitated sustainable and eco-friendly alternatives. Entomopathogenic fungi (EPF) have shown potential due to their ability to overcome resistance and have minimal impact on non-target organisms. Despite this potential, the precise physiological mechanisms by which EPF acts on insect pests remain poorly understood. To attain a comprehensive understanding of the complex physiological processes that drive the successful control of P. absoluta adults through EPF, we investigated the impacts of different Metarhizium anisopliae isolates (ICIPE 665, ICIPE 20, ICIPE 18) on the pest's survival, cellular immune responses, and gut microbiota under varying temperatures. The study unveiled that ICIPE 18 caused the highest mortality rate among P. absoluta moths, while ICIPE 20 exhibited the highest significant reduction in total hemocyte counts after 10 days at 25°C. Moreover, both isolates elicited notable shifts in P. absoluta's gut microbiota. Our findings revealed that ICIPE 18 and ICIPE 20 compromised the pest's defense and physiological functions, demonstrating their potential as biocontrol agents against P. absoluta in tomato production systems.

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As a result of climate change and global warming, plant diseases and pests are drawing attention because they are dispersing more quickly than ever before. The tomato leaf miner destroys the growth structure of the tomato, resulting in 80 to 100 percent tomato loss. Despite extensive efforts to prevent its spread, the tomato leaf miner can be found on most continents. To protect tomatoes from the tomato leaf miner, inspections must be performed on a regular basis throughout the tomato life cycle. To find a better deep neural network (DNN) approach for detecting tomato leaf miner, we investigated two DNN models for classification and segmentation. The same RGB images of tomato leaves captured from real-world agricultural sites were used to train the two DNN models. Precision, recall, and F1-score were used to compare the performance of two DNN models. In terms of diagnosing the tomato leaf miner, the DNN model for segmentation outperformed the DNN model for classification, with higher precision, recall, and F1-score values. Furthermore, there were no false negative cases in the prediction of the DNN model for segmentation, indicating that it is adequate for detecting plant diseases and pests.

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The moth species Phthorimaea absoluta (Meyrick) (formerly Tuta absoluta) is serious threat to tomato and other Solanaceous crops worldwide and is invasive throughout Europe, Asia, and Africa. While P. absoluta has not yet been found in the U.S. recent detections in the Caribbean have raised concerns that the species could be introduced to mainland North America. To improve detection capacity, a droplet digital PCR (ddPCR) assay was developed that employs a nondestructive bulk DNA extraction method able to detect one P. absoluta sample among 200 nontargets. Such high-throughput and sensitive molecular assays are essential to preventing introductions through early detection and response. This assay can also be used in areas where P. absoluta is established to monitor outbreaks and track migratory patterns.

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<b>Background and Objective:</b> The use of entomopathogenic agents for crop pest management is a viable alternative to synthetic chemical pesticides. <i>Beauveria bassiana</i> (Bals.) and <i>Metarhizium anisopliae</i> (Metsch.) are fungi considered the most promising extensively widely applied bio-control agents in protecting a wide range of economic crops. Fungal toxins are thought to play a crucial part in the pathogenicity process during insect infestation. The bioinsecticides' synergy could help to control the invasive pest more safely and effectively. <b>Materials and Methods:</b> Suspensions of Beauveroz (<i>Beauveria</i> <i>bassiana</i>) and Metarhoz-P (<i>Metarhizium anisopliae</i>), were evaluated as to their virulence against <i>T.</i> <i>absoluta</i> larvae at 3 different doses. As a comparison, Abamectin was utilized as a positive control, while water was used as a negative control. <b>Results:</b> All the commercial compounds caused significant mortality among <i>T.</i> <i>absoluta</i> larvae, with approximately 52% mortality after 5 days of the treatment. Over 5 days, mortality of <i>T.</i> <i>absoluta</i> larvae when exposed to a combined treatment of <i>B.</i> <i>bassiana</i>, <i>M.</i> <i>anisopliae</i> and Abamectin reached 92%. The results under field conditions, showed significant differences (p<0.001) among these products while adding the surfactants increased the mortality larvae. Combined treatments of these 3 commercial compounds showed a synergistic effect acceded the effect obtained using each compound alone. Bio-pesticides, <i>B.</i> <i>bassiana</i> and <i>M.</i> <i>anisopliae</i> formulations caused mortality rates among <i>T.</i> <i>absoluta</i> larvae similar to the Abamectin treatment. <b>Conclusion:</b> Observations indicated that both fungus candidates and Abamectin proved effective against <i>T. absoluta</i> larvae. The combined use showed a high potentiality indicating a positive synergistic effect.

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In nature, insects concurrently face multiple environmental stressors, a scenario likely increasing with climate change. Integrated stress resistance (ISR) thus often improves fitness and could drive invasiveness, but how physiological mechanisms influence invasion has lacked examination. Here, we investigated cross-tolerance to abiotic stress factors which may influence range limits in the South American tomato pinworm-a global invader that is an ecologically and socially damaging crop pest. Specifically, we tested the effects of prior rapid cold- and heat-hardening (RCH and RHH), fasting, and desiccation on cold and heat tolerance traits, as well as starvation and desiccation survivability between T. absoluta life stages. Acclimation effects on critical thermal minima (CTmin ) and maxima (CTmax ) were inconsistent, showing significantly deleterious effects of RCH on adult CTmax and CTmin and, conversely, beneficial acclimation effects of RCH on larval CTmin . While no beneficial effects of desiccation acclimation were recorded for desiccation tolerance, fasted individuals had significantly higher survival in adults, whereas fasting negatively affected larval tolerances. Furthermore, fasted and desiccation acclimated adults had significantly higher starvation tolerance, showing strong evidence for cross-tolerance. Our results show context-dependent ISR traits that may promote T. absoluta fitness and competitiveness. Given the frequent overlapping occurrence of these divergent stressors, ISR reported here may thus partly elucidate the observed rapid global spread of T. absoluta into more stressful environments than expected. This information is vital in determining the underpinnings of multistressor responses, which are fundamental in forecasting species responses to changing environments and management responses.

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The South American pinworm Tuta absoluta (Meyrick) (Family: Gelechiidae) is one of the most devastating lepidopteran pests in the developing countries of South America, Africa, and Asia. This pest is classified as the most serious threat for tomato production worldwide. In the present study, we analyzed RNAi-mediated control through exogenously applied dsRNA delivery on tomato. The dsRNA treatments were made to target the juvenile hormone binding protein and the v-ATPase B. Both mRNA targets were cloned, validated by sequencing, and used to produce each dsRNA. After treatments the relative transcript expression was analyzed using qRTPCR to assess to efficacy of RNAi. A leaf-dip assay was used to provide late 2nd instar larvae three feeding access periods: 24, 48, and 72 h, to evaluate the effect of gene silencing of each target. Larvae were fed tomato leaves coated with five different RNAi concentrations (10, 20, 30, 40, and 50 micrograms/centimeter-squared), that suppressed two genes (juvenile hormone protein, JHBP, and vacuolar-type adenosine triphosphatase enzyme, v-ATPase). Treatments with dsRNA showed a significant increase in mortality at 24, 48, and 72 h after ingestion (P < 0.01, α = 0.05), along with reduced leaf damage, and increased feeding deterrence. The results suggest that these two RNAi products may provide a suitable treatment for control of this and other lepidopteran pests.

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The tomato leaf miner, Tuta absoluta is a destructive pest of tomato. The leaf-mining activities of its larvae can cause significant yield losses. Real-time quantitative polymerase chain reaction (RT-qPCR) is commonly used to measure gene expression, and the selection of stable reference genes for calibration and standardization is critical for accurate use of RT-qPCR. We studied the stable expression of nine common housekeeping genes in T. absoluta. These were examined at different developmental stages, in larval tissues, as well as those induced by exposure to 20E and insecticides. Four dedicated algorithms (geNorm, BestKeeper, NormFinder, and ΔCt method) and online tool (RefFinder) were used to analyze and rank the tested reference genes. Based on the standardized gene expression data of target gene ecdysone receptor (EcR), the applicability of specific reference genes was verified. The results clarify that the optimal internal reference genes vary greatly under different experimental conditions. GAPDH and RPS11 were the best reference genes for developmental stages; RPL28 and RPL10 for different tissues; EF1α and RPL28 for 20E treatment; EF1α and RPL7A for insecticide treatments. The most suitable reference genes in all experimental conditions are EF1α and RPL28.

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The tomato leaf miner, Tuta absoluta (Meyrick), is the most important pest for tomato production in Iran. The effect of flubendiamide and thiocyclam hydrogen oxalate insecticides was assessed on cellular energy allocation (CEA) of the third instar larvae of T. absoluta ingesting six different tomato cultivars. Plant leaves were treated with LC50 concentration of both insecticides and their energy available (Ea), energy consumption (Ec), and CEA were calculated. The results showed that total energy reserves (protein, carbohydrate, and lipid budgets) were significantly reduced after exposure to insecticides and tomato secondary metabolites. The larvae fed on Riogrande and Super Chief cultivars showed the least amount of energy available after treatment with both insecticides. The highest rate of oxygen consumption was observed in larvae fed on Calj, Super Luna, and Super strain B after treatment with flubendiamide. The amount of CEA decreased in treated larvae compared to untreated larvae. This reduction was statistically higher in treated larvae that fed on Riogrande and Super strain B cultivars. Reduction in CEA is probably due to the expenses of dealing with detoxification of insecticides and plant metabolites. CEA is a suitable and primary biomarker for the effects of cultivars and insecticides as integrate and summarizes insect energy allocation in variable situations.

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The EFSA Panel on Plant Health performed a pest categorisation of Liriomyza bryoniae (Diptera: Agromyzidae) for the EU. L. bryoniae (the tomato leaf miner; EPPO code: LIRIBO) is a polyphagous Palaearctic species which probably originates from southern Europe, where it occurs commonly outdoors and has now spread to many parts of central and northern Europe, where it is only found in greenhouses. The species is also reported in North Africa and in several countries in Asia. L. bryoniae can have multiple overlapping generations per year. Eggs are inserted in the leaves of host plants. Three larval instars feed internally within leaves and stems of field vegetables. Pupation generally takes place in the soil and very occasionally on the upper or lower surfaces of the leaves. L. bryoniae is regulated in the EU by Commission Implementing Regulation (EU) 2019/2072 (Annex III) in specific protected zones only (the Republic of Ireland and Northern Ireland in the United Kingdom). However, L. bryoniae is not specifically mentioned in any of the annexes of Commission Implementing Regulation 2019/2072 concerning controls regarding certain protected zones. The wide current geographic range of L. bryoniae, both in open fields and greenhouses, suggests that it is able to establish in most areas in the EU, including the protected zones, where its hosts are present and where impact would be possible both in open fields as well as greenhouses. All criteria for consideration as a potential protected zone quarantine pest are met. Besides, being L. bryoniae widely distributed in the EU and being plants for planting the primary pathway it could also qualify as regulated non-quarantine pest (RNQP).

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Tuta absoluta Meyrick originates in South America and is now one of the most important insect pests of Solanaceae in different parts of the world, including Africa. Its control has relied primarily on chemical insecticides, which are associated with negative ecological effects. In the present study, essential oils of Ocimum gratissimum and O. kilimandscharicum were tested for repellence and fumigant toxicity on the adult stages under laboratory conditions. The oil of O. gratissimum was more repellent, but its toxicity was comparable with that of O. kilimandscharicum. The major constituents of O. gratissimum were methyl eugenol (39.5%) and eugenol (29.7%). Those of O. kilimandscharicum were camphor (47.1%) and 1.8-cineole (19.3%). Eugenol (LC50 of 0.24 µl/ml, 83.3%, RI50 = 0.15) and camphor (LC50 of 0.23 µl/ml, 89.5%, RI50 = 0.13) were more toxic (at 1 µl/ml for 24 h) and repellent than the other constituents. The results show potential of the essential oils for use in integrated management of the tomato pest.

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Tomato leaf miner (TLM), Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the most destructive tomato pests worldwide. We tested quantity and quality of tomato fruits after simultaneous use of two biological control agents, the predatory mirid bug Nesidiocoris tenuis (Reuter) and the egg parasitoid Trichogramma brassicae Bezdenko against TLM. We varied the timing of predator releases (before or after pest establishment) and the number of parasitoids released (ten or 30 females per week per m2). The highest number of fruits per cage, percentage of undamaged fruits, total yield weight, and undamaged yield weight were all obtained with predator-in-first treatments, with or without parasitoid releases. Furthermore, measures of fruit quality were also highest in predator-in-first treatments, including, highest percentage of water, greatest proportional fresh weight of carbohydrates, most lycopene, most ß-carotene, most flavonoids, and highest total chlorophyll. Thus, our findings support a predator-in-first augmentation approach for management of TLM.

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In response to attack by herbivorous insects, plants produce semiochemicals for intra- and interspecific communication. The perception of these semiochemicals by conspecifics of the herbivore defines their choice for oviposition and feeding. We aimed to investigate the role of herbivore-induced plant volatiles (HIPVs) by Tuta absoluta larvae on the oviposition choice of conspecific females on tomato plants. We performed two- choice and non-choice bioassays with plants damaged by larvae feeding and intact control plants. We also collected headspace volatiles of those plants and tested the response of female antennae on those blends with Gas Chromatography- Electro-Antennographical Detection (GC-EAD). In total 55 compounds were collected from the headspace of T. absoluta larvae-infested plants. Our results show that female moths preferred to oviposit on intact control plants instead of damaged ones. Herbivory induced the emission of hexanal, (Ζ)-3-hexen-1-ol, (E)-ß-ocimene, linalool, (Z)-3-hexenyl butanoate, methyl salicylate, indole, nerolidol, guaidiene-6,9, ß-pinene, ß-myrcene, α-terpinene, hexenyl hexanoate, ß-elemene, ß-caryophyllene and (Ε-Ε)- 4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT), one unidentified sesquiterpene and three unknown compounds. In Electroantennographic (EAG) assays, the antennae of T. absoluta females responded to hexanal, (Ζ)-3-hexen-1-ol, methyl salicylate and indole. The antennae of T. absoluta females exhibited a dose-response in EAG studies with authentic samples. Strong EAG responses were obtained for compounds induced on damaged tomato plants, as well as in nonanal, a compound emitted by both infested and control plants. These compounds could be utilized in integrated pest management of T. absoluta.

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BACKGROUND: The spatial distribution of insects is due to the interaction between individuals and the environment. Knowledge about the within-field pattern of spatial distribution of a pest is critical to planning control tactics, developing efficient sampling plans, and predicting pest damage. The leaf miner Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is the main pest of tomato crops in several regions of the world. Despite the importance of this pest, the pattern of spatial distribution of T. absoluta on open-field tomato cultivation remains unknown. Therefore, this study aimed to characterize the spatial distribution of T. absoluta in 22 commercial open-field tomato cultivations with plants at the three phenological development stages by using geostatistical analysis. RESULTS: Geostatistical analysis revealed that there was strong evidence for spatially dependent (aggregated) T. absoluta eggs in 19 of the 22 sample tomato cultivations. The maps that were obtained demonstrated the aggregated structure of egg densities at the edges of the crops. Further, T. absoluta was found to accomplish egg dispersal along the rows more frequently than it does between rows. CONCLUSION: Our results indicate that the greatest egg densities of T. absoluta occur at the edges of tomato crops. These results are discussed in relation to the behavior of T. absoluta distribution within fields and in terms of their implications for improved sampling guidelines and precision targeting control methods that are essential for effective pest monitoring and management. © 2017 Society of Chemical Industry.

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The tomato leaf miner Tuta absoluta is one of the most devastating pests for tomato crops. Digestive proteases and ß-glucosidase enzymes were investigated using general and specific substrates and inhibitors. Maximal ß-glucosidase and proteolytic activities occurred at temperature and pH optima of 30 and 40°C, 5 and 10-11 unit of pH, respectively. Zymogram analysis showed the presence of distinguished ß-glucosidase exhibiting a specific activity of about 183 ± 15 µmol min-1 mg-1. In vitro inhibition experiments suggested that serine proteases were the primary gut proteases. Gel based protease inhibition assays demonstrated that the 28 and 73 kDa proteases might be trypsin-like and chymotrypsin-like enzymes, respectively. Overall gut trypsin-like and chymotrypsin-like activities were evaluated to be about 27.2 ± 0.84 and 1.68 ± 0.03 µmol min-1 mg-1, respectively. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis showed that T. absoluta gut serine proteases are responsible for Bacillus thuringiensis Cry insecticidal proteins proteolysis. Additionally, bioassays showed that T. absoluta larvae development was more affected by the ß-glucosidases inhibitor (D-glucono-δ-lactone) than the serine proteases inhibitor (soybean trypsin inhibitor). These results are of basic interest since they present interesting data of ß-glucosidases and gut serine proteases of T. absoluta larvae.

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BACKGROUND: Previous studies have indicated the control potential of entomopathogenic nematodes (EPNs) against Tuta absoluta. Here, the potential of Steinernema feltiae, S. carpocapsae and Heterorhabditis bacteriophora is studied when applied against larvae of T. absoluta inside leaf mines in tomato leaf discs by means of an automated spray boom. RESULTS: The studied EPN species were effective against all four larval instars of T. absoluta but caused higher mortality in the later instars (e.g. fourth instar: 77.1-97.4% mortality) than in the first instars (36.8-60.0% mortality). Overall, S. feltiae and S. carpocapsae yielded better results than H. bacteriophora. Steinernema carpocapsae and H. bacteriophora performed better at 25 °C (causing 55.3 and 97.4% mortality respectively) than at 18 °C (causing 12.5 and 34.2% mortality respectively), whereas S. feltiae caused 100% mortality at both temperatures. Under optimal spraying conditions and with the use of Addit and Silwet L-77 adjuvants, a reduced dosage of 6.8 infective juveniles (IJs) cm(-2) yielded equally good control as a recommended dosage of 27.3 IJs cm(-2) . CONCLUSION: Under laboratory conditions, S. feltiae and S. carpocapsae showed good potential against the larvae of T. absoluta inside tomato leaf mines. Results need to be confirmed in greenhouse experiments. © 2015 Society of Chemical Industry.

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BACKGROUND: Phthalic and anthranilic diamides comprise a new insecticide class recently registered in Brazil to control Lepidoptera such as Tuta absoluta (Meyrick). Therefore, the baseline of susceptibility was determined for eight representative field populations of this species to establish a resistance monitoring programme. The potential for cross-resistance as well as detoxification metabolism was assessed in order to fine-tune the resistance management programme. RESULTS: Brazilian populations were very susceptible to chlorantraniliprole (LC50 values varied from 3.17 to 29.64 µg AI L(-1) ), cyantraniliprole (LC50 values varied from 8.61 to 28.95 µg AI L(-1) ) and flubendiamide (LC50 values varied from 94 to 230 µg AI L(-1) ), with respective resistance ratios of 9.33-, 3.36- and 2.45-fold between most susceptible and tolerant populations. Anthranilic diamides showed significant correlations between log LC50 values among themselves, suggesting a high risk of cross-resistance. However, the log LC50 values of T. absoluta to phthalic diamide did not show any correlation with anthranilic diamides. Cytochrome- P450-dependent monooxygenase activity showed a weak correlation with log LC50 values of T. absoluta populations to anthranilic diamides, which suggests a potential route for evolving resistance to anthranilic diamides. CONCLUSION: The diamides were highly effective against T. absoluta, with populations showing a homogeneous response to them. Cross-resistance is very likely between anthranilic diamides in T. absoluta. Populations of this pest may evolve resistance by increasing cytochrome- P450-dependent monooxygenases.

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A traça Tuta absoluta (Meyrick) é o inseto-praga que mais compromete a produção do tomateiro. Basear o seu controle no uso de inseticidas sintéticos pode comprometer a cultura em termos econômicos e ambientais. Como alternativa de controle, o óleo de nim foi aplicado em folhas de tomateiro, avaliando os efeitos inseticida e antialimentar por ação sistêmica e translaminar. No ensaio para avaliar a ação translaminar, o óleo diluído em água foi aplicado na superfície adaxial dos folíolos, em concentrações de 0,5, 1, 5 e 10%. A mortalidade observada variou entre 49 e 100%, e o tamanho médio das minas, entre 1,62 e 0,34 cm. Nos tratamentos representados por água e água + emulsificante (5%), a mortalidade não ultrapassou 20%, com tamanho médio das minas de 1,63 cm. O estudo da ação sistêmica foi realizado ao aplicar o óleo de nim na superfície adaxial e abaxial de todas as folhas das plantas, à exceção daquelas em que as lagartas foram infestadas. Neste ensaio, o óleo foi aplicado nas concentrações de 1, 2,5 e 5%, diluídos em água e emulsificante. Observou-se que a mortalidade foi maior que 90% quando o óleo foi aplicado nas concentrações de 2,5 e 5%, sendo o tamanho médio das minas inferior a 1,0 cm. Não ocorreu mortalidade nos tratamentos controle, mas o tamanho das minas foi, em média, de 1,96 cm. Desta maneira ficou evidenciado que o óleo de nim apresenta efeito inseticida e antialimentar sobre lagartas de T. absoluta, com a propriedade de ser incorporado e translocado através das folhas de tomateiro.(AU)

The leaf miner Tuta absoluta (Meyrick) is the pest that mostly jeopardizes tomato production. The use of synthetic pesticides for its control can affect the crop economically and environmentally. As an alternative form of control, neem oil was applied on tomato leaves in order to assess antifeedant and insecticidal effects by systemic and translaminar action. In experiment for translaminar action, oil diluted in water was applied to the adaxial surface of leaflets at concentrations of 0.5, 1, 5 and 10%. The mortality rate ranged between 49 and 100%, and the average size of the mines, between 1.62 and 0.34 cm. In treatments represented by water and water + emulsifier (5%), mortality did not surpass 20%, with the average size of mines reaching 1.63 cm. The study of systemic action was performed by applying neem oil to the adaxial and abaxial surfaces of all leaves, except those that were infested by caterpillars. In this assay, the oil was applied at concentrations of 1, 2.5 and 5%, being diluted in water and emulsifiers. We observed that the mortality rate exceeded 90% when the oil was applied at concentrations of 2.5 and 5%, and the average size of mines was smaller than 1.0 cm. There was no mortality in the control treatments, but the mine size was on average 1.96 cm. Therefore, it is clear that the neem oil has an insecticidal and anti-food effect on T. absoluta caterpillars, and is possible to be incorporated and applied on tomato leaves.(AU)

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The activity of Metarhizium anisopliae and Beauveria bassiana towards eggs and larvae of Tuta absoluta (Meyrick) was evaluated. Our data showed that the isolates were pathogenic to both developmental stages tested and the eggs were more susceptible than the 1st instars. The isolates URPE-6 and URPE-19 of M. anisopliae were more pathogenic to eggs and larvae, respectively. The compatibility of these two isolates with the insecticides chlorfenapyr, spinosad, indoxacarb, abamectin, and neem were evaluated. Spinosad and indoxacarb were compatible with the two M. anisopliae isolates in all tested concentrations. At the average recommended concentration, chlorfenapyr was compatible to URPE-6 and abamectin to UFPE-19. The use of entomopathogenic fungi associated with compatible insecticides may be a useful alternative to control T. absoluta.

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