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Although food is produced in aquaponics systems worldwide, no information is available on the occurrence of insect pests and natural enemies in aquaponic lettuce, Lactuca sativa L. In this study, a survey was carried out in an aquaponic system combining lettuce with lambari, Astyanax altiparanae (Garutti & Briski), aiming to determine the insect pests and natural enemies associated with this system. We also determined the predominant insect species and the effect of meteorological factors on their populations. Insect abundance was estimated by visual sampling during 13 cultivation cycles, totaling 27 sampling dates. The meteorological factors considered were air temperature and relative humidity, and their effects were determined using the Pearson correlation. The thrips Frankliniella schultzei (Trybom) and Caliothrips phaseoli (Hood) and the aphid Aphis spiraecola (Patch) predominated. Ambient temperature and relative humidity were essential factors affecting C. phaseoli and F. schultzei. The natural enemies found on the lettuce plants were the thrips Franklinothrips vespiformis (Crawford) and Stomatothrips angustipennis (Hood) and the ladybugs Cycloneda sanguinea L., Eriopis connexa (Germar), and Hippodamia convergens (Guérin-Méneville). These results constitute the first step for a lettuce-integrated pest-management program in aquaponics systems.

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The peanut thrips, Enneothrips enigmaticus (Thysanoptera: Thrypidae), is an important pest of the peanut (Arachis hypogaea) in South America. Due to concerns about the environment and human health induced by the extensive use of pesticides in the management control of pests, environmentally and friendlier tactics must be targeted. Thus, this study investigates, for the first time, the behavior of Xylocoris sordidus (Hemiptera: Anthocoridae) as a biological control agent for E. enigmaticus. The methodology included no-choice tests to assess whether the predation rate varies according to the developmental stage of the prey, as well as the predator's developmental stage with the highest predation capacity. Additionally, an analysis of the functional response of adult and 5th instar nymphs of X. sordidus exposed to different densities of E. enigmaticus nymphs (1, 2, 4, 8, 16, and 32) was conducted. The results confirm the predation of peanut thrips by X. sordidus, with a higher predation rate in the nymphal stages of the prey. There was no difference in predation capacity between predator nymphs and adults, and exhibiting a type II functional response. Therefore, the potential of X. sordidus as a biological control agent for E. enigmaticus is confirmed, showing the importance of adopting measures to preserve this predator in peanut crops.

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Past research has characterized the induction of plant defenses in response to chewing insect damage. However, little is known about plant responses to piercing-sucking insects that feed on plant cell-contents like thrips (Caliothrips phaseoli). In this study, we used NMR spectroscopy to measure metabolite changes in response to six days of thrips damage from two field-grown soybean cultivars (cv.), known for their different susceptibility to Caliothrips phaseoli. We observed that thrips damage reduces sucrose concentration in both cultivars, while pinitol, the most abundant leaf soluble carbohydrate, is induced in cv. Charata but not in cv. Williams. Thrips did not show preference for leaves where sucrose or pinitol were externally added, at tested concentration. In addition, we also noted that cv. Charata was less naturally colonized and contained higher levels of trigonelline, tyrosine as well as several compounds that we have not yet identified. We have established that preference-feeding clues are not dependent on the plants major soluble carbohydrates but may depend on other types of compounds or leaf physical characteristics.

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Abstract Field survey study was conducted season (2017). Soybeans and weeds were weekly sampled randomly. Thrips adults were identified and counted. Detection of the virus isolate and the natural incidence was determined using; Mechanical transmission, host range, DAS-ELISA, RT-PCR. The natural incidence thrips individuals was detected depending on the SVNV% in thrips individuals and weeds hosts. Ten thrips species were associated with soybean plants in the field. The most abundant species was T. tabaci, average 256.5 average no.of individuals, followed by F. occidentalis (142.5 average no. of individuals), then N. variabilis (86.6/ average no. of individuals). Fourteen thrips species occurred on 5 legumes field crops and 41 weed plant species within soybean field. The highest average number 40.6.of individuals were recorded on Ammi majus. While the lowest one 3.3 average no. of individuals were on Urtica urens. Only 21diagnostic plant species were susceptible to infection with SVNV. G. max and Vigna radiate, were the highest percentage of infection 80% followed by V. unguilata & N. benthamiana, 75%. Egyptian isolate of Soybean vein necrosis virus (SVNV) in this study showed a high degree of similarity and it is closely related to TSWV from Egypt (DQ479968) and TCSV from USA (KY820965) with nucleotide sequence identity of 78%. Four thrips species transmitted SVNV (F. fusca 4.0%, F. schultzei 4.3%, F. tritici 3.3% and N. variabilis 68.0% transmission). Both C. phaseoli and M. sjostedti can acquire the virus but unable to transmit it. The following species; T. tabaci, F. occidentalis, S. dorsallis and T. palmi cannot acquire or transmit SVNV. The incidence of SVNV in the field started by the end of July then increased gradualy from 12.7 to 71.3% by the end of the season. In conclusion, few thrips individuals invaded soybean crops are enough to transmit high rate of SVNV within the crop. Furthermore, several vector species are also abundant on weeds, which are the major sources of soybean viruses transmitted to the crops. This information might be important for control and reduce the incidence of SVNV infection.

Resumo O estudo de pesquisa de campo foi realizado na temporada (2017). A soja e as ervas daninhas foram amostradas semanalmente de forma aleatória. Tripes adultos foram identificados e contados. A detecção do vírus isolado e a incidência natural foram determinadas usando transmissão mecânica, gama de hospedeiros, DAS-ELISA, RT-PCR. A incidência natural de tripes em indivíduos foi detectada dependendo da % de SVNV em tripes e hospedeiros infestantes. Dez espécies de tripes foram associadas a plantas de soja no campo. A espécie mais abundante foi T. tabaci, com média de 256,5 número médio de indivíduos, seguida por F. occidentalis (142,5) e N. variabilis (86,6 / número médio de indivíduos). Catorze espécies de tripes ocorreram em 5 culturas de leguminosas e 41 espécies de plantas daninhas dentro de campos de soja. O maior número médio de 40,6 indivíduos foi registrado em Ammi majus. Enquanto o mais baixo, 3,3 número médio de indivíduos, foi no Urtica urens. Apenas 21 espécies de plantas diagnosticadas foram suscetíveis à infecção com SVNV. G. max e Vigna radiate foram os maiores percentuais de infecção, 80%, seguidos por V. unguilata e N. benthamiana, 75%. O isolado egípcio neste estudo mostrou um alto grau de similaridade e está intimamente relacionado ao TSWV do Egito (DQ479968) e ao TCSV dos EUA (KY820965), com identidade de sequência de nucleotídeos de 78%. Quatro espécies de tripes transmitiram SVNV (F. fusca 4,0%, F. schultzei 4,3%, F. tritici 3,3% e N. variabilis 68,0% de transmissão). Tanto C. phaseoli quanto M. sjostedti podem adquirir o vírus, mas não podem transmiti-lo. As seguintes espécies, T. tabaci, F. occidentalis, S. dorsallis e T. palmi não podem adquirir ou transmitir SVNV. A incidência de SVNV no campo, iniciada no final de julho, aumentou gradativamente de 12,7 para 71,3% no final da temporada. Em conclusão, poucos indivíduos de tripes invadiram a cultura da soja e são suficientes para transmitir alta taxa de SVNV dentro da cultura. Além disso, várias espécies de vetores também abundam em ervas daninhas, que são as principais fontes dos vírus da soja transmitidos às lavouras. Essas informações podem ser importantes para controlar e reduzir a incidência de infecção por SVNV.

RESUMO

Abstract Field survey study was conducted season (2017). Soybeans and weeds were weekly sampled randomly. Thrips adults were identified and counted. Detection of the virus isolate and the natural incidence was determined using; Mechanical transmission, host range, DAS-ELISA, RT-PCR. The natural incidence thrips individuals was detected depending on the SVNV% in thrips individuals and weeds hosts. Ten thrips species were associated with soybean plants in the field. The most abundant species was T. tabaci, average 256.5 average no.of individuals, followed by F. occidentalis (142.5 average no. of individuals), then N. variabilis (86.6/ average no. of individuals). Fourteen thrips species occurred on 5 legumes field crops and 41 weed plant species within soybean field. The highest average number 40.6.of individuals were recorded on Ammi majus. While the lowest one 3.3 average no. of individuals were on Urtica urens. Only 21diagnostic plant species were susceptible to infection with SVNV. G. max and Vigna radiate, were the highest percentage of infection 80% followed by V. unguilata & N. benthamiana, 75%. Egyptian isolate of Soybean vein necrosis virus (SVNV) in this study showed a high degree of similarity and it is closely related to TSWV from Egypt (DQ479968) and TCSV from USA (KY820965) with nucleotide sequence identity of 78%. Four thrips species transmitted SVNV (F. fusca 4.0%, F. schultzei 4.3%, F. tritici 3.3% and N. variabilis 68.0% transmission). Both C. phaseoli and M. sjostedti can acquire the virus but unable to transmit it. The following species; T. tabaci, F. occidentalis, S. dorsallis and T. palmi cannot acquire or transmit SVNV. The incidence of SVNV in the field started by the end of July then increased gradualy from 12.7 to 71.3% by the end of the season. In conclusion, few thrips individuals invaded soybean crops are enough to transmit high rate of SVNV within the crop. Furthermore, several vector species are also abundant on weeds, which are the major sources of soybean viruses transmitted to the crops. This information might be important for control and reduce the incidence of SVNV infection.

Resumo O estudo de pesquisa de campo foi realizado na temporada (2017). A soja e as ervas daninhas foram amostradas semanalmente de forma aleatória. Tripes adultos foram identificados e contados. A detecção do vírus isolado e a incidência natural foram determinadas usando transmissão mecânica, gama de hospedeiros, DAS-ELISA, RT-PCR. A incidência natural de tripes em indivíduos foi detectada dependendo da % de SVNV em tripes e hospedeiros infestantes. Dez espécies de tripes foram associadas a plantas de soja no campo. A espécie mais abundante foi T. tabaci, com média de 256,5 número médio de indivíduos, seguida por F. occidentalis (142,5) e N. variabilis (86,6 / número médio de indivíduos). Catorze espécies de tripes ocorreram em 5 culturas de leguminosas e 41 espécies de plantas daninhas dentro de campos de soja. O maior número médio de 40,6 indivíduos foi registrado em Ammi majus. Enquanto o mais baixo, 3,3 número médio de indivíduos, foi no Urtica urens. Apenas 21 espécies de plantas diagnosticadas foram suscetíveis à infecção com SVNV. G. max e Vigna radiate foram os maiores percentuais de infecção, 80%, seguidos por V. unguilata e N. benthamiana, 75%. O isolado egípcio neste estudo mostrou um alto grau de similaridade e está intimamente relacionado ao TSWV do Egito (DQ479968) e ao TCSV dos EUA (KY820965), com identidade de sequência de nucleotídeos de 78%. Quatro espécies de tripes transmitiram SVNV (F. fusca 4,0%, F. schultzei 4,3%, F. tritici 3,3% e N. variabilis 68,0% de transmissão). Tanto C. phaseoli quanto M. sjostedti podem adquirir o vírus, mas não podem transmiti-lo. As seguintes espécies, T. tabaci, F. occidentalis, S. dorsallis e T. palmi não podem adquirir ou transmitir SVNV. A incidência de SVNV no campo, iniciada no final de julho, aumentou gradativamente de 12,7 para 71,3% no final da temporada. Em conclusão, poucos indivíduos de tripes invadiram a cultura da soja e são suficientes para transmitir alta taxa de SVNV dentro da cultura. Além disso, várias espécies de vetores também abundam em ervas daninhas, que são as principais fontes dos vírus da soja transmitidos às lavouras. Essas informações podem ser importantes para controlar e reduzir a incidência de infecção por SVNV.

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The functional responses of Chrysoperla carnea larvae were evaluated at different seven densities of the 3rd instar nymphs of Aphis craccivora and Gynaikothrips ficorum in order to find out the relationship between predator densities and its prey by the, and also to find out their capability for biological control of aphids and thrips. Results revealed that all tested larval instars of Ch. carnea exhibited a type II response in relation to the prey. Moreover, the coefficients of attack rate (a) and handling time (Th) was differed among various growing instars of predator and for the prey species. The 3rd instar larvae of Ch. carnea manifested the highest attacking rate (1.23 and 1.22) on the 3rd instar nymphs of A. craccivora and G. ficorum, respectively. In addition it exhibited the highest maximum predation (Na max) (50.00 and 52.63) on A. craccivora and G. ficorum nymphs, respectively as compared with the other treatments. Accordingly, Ch. carnea could be considered as a promising bio-control agent for A. craccivora and G. ficorum management.

As respostas funcionais de larvas de Chrysoperla carnea foram avaliadas em sete diferentes densidades de ninfas de 3º instar de Aphis craccivora e Gynaikothrips ficorum, a fim de descobrir a relação entre as densidades de predadores e suas presas, e sua capacidade de controle biológico de pulgões e tripes. Os resultados revelaram que todos os instares larvais testados de Ch. carnea apresentaram resposta de tipo II em relação à presa. Além disso, os coeficientes de taxa de ataque (a) e tempo de manejo (Th) diferiram entre os vários instares de crescimento do predador e para a espécie de presa. As larvas de 3º instar de Ch. carnea manifestaram a maior taxa de ataque (1,23 e 1,22) nas ninfas de 3º instar de A. craccivora e G. ficorum, respectivamente. Além disso, a maior taxa de predação máxima (Na máx.) (50,00 e 52,63) apresentou-se em ninfas de A. craccivora e G. ficorum, respectivamente, em comparação aos demais tratamentos. Assim, é possível concluir que o Ch. carnea pode ser considerado um agente de biocontrole promissor para o manejo de A. craccivora e G. ficorum.

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Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) is an invasive pest that is popularly known as chilli thrips. This insect pest has a wide range of hosts distributed across 72 plant families, causing damage to numerous crops of great economic importance. In the Americas, it is present in the USA, Mexico, Suriname, Venezuela, Colombia, and some Caribbean Islands. Knowing the regions which have environmentally suitable conditions for the survival of this pest is important for phytosanitary monitoring and inspection. Thus, our objective was to forecast the distribution potential of S. dorsalis with a focus on the Americas. Models were produced to design this distribution, in which the environmental variables used were made available in Wordclim version 2.1. The algorithms used for the modeling were the generalized additive model (GAM), generalized linear model (GLM), maximum entropy (MAXENT), random forest (RF), and Bioclim, in addition to the ensemble, which consisted of the grouping of the algorithms used. The metrics used to evaluate the models were area over the curve (AUC), true ability statistics (TSS), and Sorensen score. All models had satisfactory results (> 0.8) for all metrics used. In North America, the model showed favorable regions on the west coast of the USA and east coast near New York. In South America, the potential distribution of the pest is significant, encompassing regions in all countries. It is concluded that S. dorsalis has suitable areas for the occurrence in the three American subcontinents and, in particular, a large part of South America.

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Sampling plans are an essential part of integrated pest management programs. Sequential sampling plans enable rapid and low-cost assessment of pest densities. Thrips are emerging pests in soybean crops, and the main method used in pest control is chemical. In soybean crops, insecticides are applied mainly using tractors or airplanes. Thus, this work aimed to determine sequential sampling plans for thrips in soybean crops with insecticide applications using a tractor or airplane. Data were collected in 56 soybean fields, and each field was 20 ha. Sampling plans were determined and validated. The lower (m0) and upper (m1) limits of the sequential sampling plans were: m0 = 1.72 and m1 = 3.43 (by tractor applications) and, m0 = 2.27 and m1 = 4.53 thrips. sample-1 (by airplane applications). The slope (S) and the lower (h0) and upper (h1) intercepts of the sequential sampling plans were: S = 2.42, h0 = -5.79, and h1 = 5.79 (by tractor applications) and, S = 3.19, h0 = -6.83, and h1 = 6.83 (by airplane applications). Sequential sampling plans allowed for correct decisions to be made in all situations using a maximum of 10 samples. The sequential plan reduced the sampling effort by over 87% compared to conventional sampling plans. Therefore, these control decision-making systems have proven feasible and advantageous for implementing integrated pest management programs for controlling thrips species in soybean crops.

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Heliothrips haemorrhoidalis is a polyphagous thrips species that has been reported as a potential pest in strawberry cultivation in Brazil. Since it has only recently emerged as a pest species in production areas, understanding seasonal trends in the species' activity is particularly important for designing management strategies. Therefore, this study aims to investigate the influence of climate factors (temperature and relative humidity) and six strawberry cultivars ('Albion', 'Aromas', 'Camino Real', 'Monterey', 'Portola', and 'San Andreas') on the population dynamics of H. haemorrhoidalis during the 2018-2019 and 2019-2020 growing seasons in southern Brazil. The greatest peak in thrips populations in the cultivars assessed occurred between January and March (summer) in both growing seasons. The relationship between the incidence of H. haemorrhoidalis and temperature was observed to be negative during the autumn, spring, and summer months but positive during winter. Relative humidity levels above 70% had a negative influence on the abundance of insects. Populations of H. haemorrhoidalis varied between the cultivars as follows: 'Aromas' > 'Monterey' > 'San Andreas' > 'Albion' > 'Camino Real' > 'Portola'. Cross-sections of strawberry leaves showed that 'Monterey' had the highest density of nonglandular trichomes/mm2 (7.26), while 'Portola' cultivar, the greatest predominance of glandular trichomes/mm2 (12.67), which may have contributed to the incidence of H. haemorrhoidalis. The demographic information presented on H. haemorrhoidalis in strawberry cultivars provides a starting point to better understand the insect's population dynamics. These results also indicate that climatic conditions are a limiting factor for the development of H. haemorrhoidalis.

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Pseudophilothrips ichini is a recently approved biological control agent for the highly invasive Brazilian peppertree in Florida, USA. Prior to approval for field release in 2019, thrips colonies used for host specificity testing were produced and maintained in small cylinders to fit in restricted quarantine spaces. This next segment in the classical biological control pipeline is mass production and distribution of P. ichini. To accomplish this, we developed novel techniques to expand from small colony maintenance to large-scale production. We first quantified the productivity of the small cylinders, each containing a 3.8 L potted plant and producing an average of 368 thrips per generation. Given the amount of maintenance the cylinders required, we investigated larger cages to see if greater numbers of thrips could be produced with less effort. Acrylic boxes (81.5 × 39.5 × 39.5 cm) each contained two 3.8 L plants and produced an average of 679 thrips per generation. The final advancement was large, thrips-proof Lumite® screen cages (1.8 × 1.8 × 1.8 m) that each held six plants in 11.4 L pots and produced 13,864 thrips in as little as 5 wk. Screen cages and cylinders had the greatest thrips fold production, but screen cages required ten times less labor per thrips compared to either cylinders or boxes. The efficiency of these large screen cages ensured sustained mass production and field release capacity in Schinus-infested landscapes. The screen cage method is adapted and used by collaborators, and this will expand the literature on beneficial thrips mass rearing methods.

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Thrips hawaiiensis (Morgan) is a flower-inhabiting thrips with a wide range of host plants, but little is known regarding its biological and ecological characteristics on vegetable hosts. Here, we evaluated the development, survival, and oviposition of T. hawaiiensis on five vegetable species (Capsicum annuum, Solanum melongena, Cucurbita moschata, Lablab purpureus, and Brassica oleracea), and constructed its life tables on these vegetables. There were significant differences in the development of T. hawaiiensis on the five vegetables, and the developmental times from egg to adult were 12.19 days, 11.59 days, 11.12 days, 10.78 days, and 10.51 days on C. moschata, B. oleracea, L. purpureus, C. annuum, and S. melongena, respectively. There were also significant differences in T. hawaiiensis' survival rate on these plants, with S. melongena (71.00%) > C. annuum (67.33%) > L. purpureus (63.33%) > B. oleracea (57.00%) > C. moschata (49.33%). The greatest and lowest fecundity levels of T. hawaiiensis were found on S. melongena (44.28) and C. moschata (30.16), respectively. T. hawaiiensis had the greatest net reproductive rate on S. melongena (19.22), followed by C. annuum (16.11), L. purpureus (15.17), B. oleracea (11.10), and C. moschata (8.47), and the intrinsic rate of increase showed a similar trend, with values of 0.140, 0.125, 0.121, 0.112, and 0.093, respectively. Thus, S. melongena and C. moschata were the most and least suitable hosts for the population development of T. hawaiiensis among the five tested vegetable hosts. This study could provide important information for the key control of T. hawaiiensis on different crops.

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The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. Momordica fruits originating from countries where Thrips palmi is known to occur qualify as high risk plants. This Scientific Opinion covers the introduction risk for T. palmi posed by fruits of Momordica charantia L. imported from Honduras, taking into account the available scientific information, including the technical information provided by the National Service of Agrifood Health and Safety (SENASA) of Honduras. The risk mitigation measures proposed in the technical dossier from Honduras were evaluated taking into account the possible limiting factors. An expert judgement is given on the likelihood of pest freedom taking into consideration the potential pest pressure in the field, the risk mitigation measures acting on the pest in the field and in the packinghouse, including uncertainties associated with the assessment. For T. palmi on M. charantia fruits from Honduras, an expert judgement is given on the likelihood of pest freedom following the evaluation of the risk mitigation measures acting on T. palmi, including any uncertainties. The Expert Knowledge Elicitation indicated, with 95% certainty that between 9,406 and 10,000 M. charantia fruits per 10,000 will be free from T. palmi.

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The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. M. charantia fruits originating from countries where Thrips palmi is known to occur qualify as high-risk plants. This Scientific Opinion covers the introduction risk for T. palmi posed by fruits of Momordica charantia L. imported from Suriname, taking into account the available scientific information, including the technical information provided by the National Plant Protection Organization of Suriname. The risk mitigation measures proposed in the technical dossier from Suriname were evaluated taking into account the possible limiting factors. An expert judgement is given on the likelihood of pest freedom taking into consideration the potential pest pressure in the field, the risk mitigation measures acting on the pest in the field and in the packinghouse, including uncertainties associated with the assessment. For T. palmi on M. charantia fruits from Suriname, an expert judgement is given on the likelihood of pest freedom following the evaluation of the risk mitigation measures acting on T. palmi, including any uncertainties. The Expert Knowledge Elicitation indicated, with 95% certainty that between 8,652 and 10,000 M. charantia fruits per 10,000 will be free from T. palmi.

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The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. Momordica fruits originating from countries where Thrips palmi is known to occur qualify as high risk plants. This Scientific Opinion covers the introduction risk for T. palmi posed by fruits of Momordica charantia L. imported from Mexico, taking into account the available scientific information, including the technical information provided by the National Service of Health, Safety and Agrifood Quality (Senasica) of Mexico. The risk mitigation measures proposed in the technical dossier from Mexico were evaluated taking into account the possible limiting factors. An expert judgement is given on the likelihood of pest freedom taking into consideration the potential pest pressure in the field, the risk mitigation measures acting on the pest in the field and in the packinghouse, including uncertainties associated with the assessment. For T. palmi on M. charantia fruits from Mexico, an expert judgement is given on the likelihood of pest freedom following the evaluation of the risk mitigation measures acting on T. palmi, including any uncertainties. The Expert Knowledge Elicitation indicated, with 95% certainty that between 9,492 and 10,000 M. charantia fruits per 10,000 will be free from T. palmi.

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The organic banana is one of the most popular products worldwide and its popularity is mainly due to its excellent nutritional properties and tasty flavor. Peru is considered one of the major producers and exporters of this product, being the city of Piura the main region with most of the national agro-producers. It is also considered a key factor in the development of the economy of this region as it creates job opportunities because of the productive chain required in the process (harvest, post-harvest, and export). The main problem faced by producers is the existence of pests such as Red spot thrips, Black Sigatoka, and others, which affect the production and the quality of the final product. Therefore, this article aims to propose an alternative solution, using the 4.0 Industry technology as well as the installation of an IoT sensor network in banana plantations in order to develop a model which estimates the classification of the pest incidence level based on Machine learning techniques, making use of the atmospheric variables measured with the IoT sensor network as input data. In the research, we have used The Support Vector Machine techniques, which have successfully achieved models with a high level of accuracy. The implementation of this system aims to help producers improve the management of pest control by scheduling spraying dates more effectively, optimizing not only the quality of the product but also reducing costs.

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After the revision of the genus Holopothrips provided by Lindner et al. (2018), the specimens of Holopothrips kept in the CIRAD/CBGP collection collected in Guadeloupe were re-examined. Two species previously identified as Holopothrips tenuis and Holopothrips sp. are described here as H. brevisetus sp. n. and H. guadeloupensis sp. n. Holopothrips ananasi is here removed from the list of species reported to Guadeloupe after re-examination of labelled specimens. Information on all the species of Holopothrips found in Guadeloupe, and an identification key to the species of Holopothrips recorded from the Caribbean are provided.

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Spatial distribution studies of insect pests make it possible to determine their colonization and dispersal patterns. Watermelon (Citrullus lanatus (Thunb.) Matsum. et Nakai) is among the most frequently consumed fruits in the world, and the common blossom thrips, Frankliniella schultzei (Trybom) (Thysanoptera: Thripidae), is one of the most important insect pests of this plant. The objective of this study was to determine the spatial distribution of F. schultzei in commercial watermelon crops using geostatistics. The studied F. schultzei populations presented an aggregated distribution. The colonization of thrips began at the borders of the crops, especially in the areas located in the opposite direction to that of the prevailing winds. The highest densities of thrips occurred in crops that had cucurbits in the surrounding areas. When monitoring for F. schultzei populations, greater attention should be given to sampling that part of the crop located in the opposite direction to that of the prevailing winds because this is where colonization begins. Even at low densities, the aggregation points of thrips in the crop should be located and controlled so that they do not cause damage. In sampling programs for F. schultzei, samples should be taken at distances greater than 9 m apart because this is the distance up to which densities of this species show spatial dependence. Planting watermelon crops close to other cucurbits should be avoided, as these alternate hosts may act as a source of infestation by this pest.

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Abstract Frankliniella zucchini transmits zucchini lethal chlorosis virus, causal agent of lethal chlorosis of zucchini squash. The characteristics of relationship between this virus with its vector have not been studied, one of the reasons being the lack of a method for rearing the thrips for laboratory studies. This work proposes a system for the rearing of F. zucchini on fresh virus free zucchini 'Caserta' fruits, offering a practical and efficient alternative for the supply of a large number of insects for later study of virus/vector relationship. In addition, to aid in the identification of this species of thrips, the immature and adult forms obtained from the colony were described.

RESUMO

Thysanoptera-induced galls commonly culminate in simple folding or rolling leaf gall morphotypes. Most of these galls are induced by members of the suborder Tubulifera, with only a few species of the suborder Terebrantia being reported as gall inducers. The Terebrantia, as most of the gall inducers, manipulates the host plant cellular communication system, and induces anatomical and biochemical changes in its host plant. In an effort to keep its homeostasis, the host plant reacts to the stimuli of the galling insect and triggers chemical signaling processes. In contrast to free-living herbivores, the signaling processes involving galling herbivores and their host plants are practically unknown. Current investigation was performed into two steps: first, we set the structural profile of non-galled and galled leaves, and looked forward to find potential alterations due to gall induction by an undescribed species of Nexothrips (suborder Terebrantia) on Myrcia splendens. Once oil glands had been altered in size and number, the second step was the investigation of the chemical profile of three tissue samples: (1) non-galled leaves of a control individual, (2) non-galled leaves of galled plants, and (3) galls. This third sample was divided into two groups: (3.1) galls from which the inducing thrips were manually removed and (3.2) galls macerated with the inducing thrips inside. The chemical profile was performed by gas chromatography/ mass spectrometric detector after headspace solid-phase extraction. The galling activity of the Nexothrips sp. on M. splendens culminates in mesophyll compactness interspersed to diminutive hypersensitive spots, development of air cavities, and the increase in size and number of the secretory glands. Seventy-two compounds were completely identified in the volatile profile of the three samples, from which, sesquiterpenes and aldehydes, pertaining to the "green leaf volatile" (GLVs) class, are the most abundant. The rare event of gall induction by a Terebrantia revealed discrete alterations toward leaf rolling, and indicated quantitative differences related to the plant bioactivity manipulated by the galling thrips. Also, the content of methyl salicylate has varied and has been considered a potential biomarker of plant resistance stimulated as a long-distance effect on M. splendens individuals.