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Mealybugs are agricultural pests occurring all over the world. The Sao Francisco Valley is one of the most productive regions regarding the cultivation of fruit crops in Brazil, demanding a proper phytosanitary management that can be obtained through the biological control of pests. Fortnight samples of mealybugs associated with roots, trunk, leaves and fruits of grapevines, pear, apple, persimmon, guava and Barbados cherry were performed in commercial farms in the sub-medium Sao Franciso Valley, Brazil, during twelve months. In order to identify mealybugs based on morphological characteristics from adult female specimens, samples were stored in Eppendorf tubes containing ethanol 70%, labeled and then identified. A total of 10,189 mealybugs, including nymphs and adult females were collected, with the highest number of specimens found in grapevines. The second most affected crop was persimmon, followed by pear. The lowest infestation was observed in guava, apple and Barbados cherry. Pseudococcidae evidenced preference for fruits. The following mealybugs were observed in the sub-medium region of the Sao Francisco Valley: Planococcus sp., Planococcus citri, Phenacoccus solenopsis, Dysmicoccus brevipes, Maconellicoccus hirsutus, Ferrisia virgata and Pseudococcus elisae. Made available in DSpace on 2022-10-21T14:09:14Z (GMT). No. of bitstreams: 1 Mealybugs-on-fruit-crops-in-the-Sao-Franciso-Valley-2021.pdf: 406403 bytes, checksum: 63dd9e1ae8377c4a52b1fca53ddbdcd3 (MD5) Previous issue date: 2021

Diadiplosis multifila was recently discovered feeding on Planococcus citri eggs in vineyards in the semi-arid northeast region of Brazil. The objective of the present paper was to study the biology of D. multifila in P. citri under constant temperatures of 22, 25, 28, and 31 °C. We evaluated its embryonic stage, egg viability, development period, survival of larva and pupa, longevity, average number of eggs, and sex ratio. D. multifila completed its life cycle in all temperatures except for 31 °C. The length of the embryonic period ranged from 4 to 7 days. The larval stage was longer at a temperature of 22 °C (8.6 days) and shorter at 28 °C (6.4). The pupal stage exhibited durations of 12.9, 10.4, and 8.2 days for temperatures of 22, 25, and 28 °C, respectively. The average viability in the larval stage was 97% and 83% in the pupal stage. The total life cycle took 16.7 (28 °C), 20 (25 °C), and 27 (22 °C) days to complete. The adults lived for approximately 2 days and the females produced on average 34, 25, and 19 eggs at temperatures of 22, 25, and 28 °C, respectively. The sex ratio varied from 0.46 to 0.54. Made available in DSpace on 2020-02-20T18:08:47Z (GMT). No. of bitstreams: 1 BiologyofDiadiplosismultifila2019.pdf: 353466 bytes, checksum: 295e222ff095994d4c65f2c9aeb652f7 (MD5) Previous issue date: 2019

Pseudococcidae species, also known as mealybugs, comprises a complex of pests in various cultivated and non-cultivated plant species, among which fruit plants are most affected by both direct and indirect damage. The incidence of these pest species has been constant in productive environments, causing significant losses due to sap suction, virus transmission, and damage to fruit quality. Thus, this study aimed to know and investigate the population dynamics of natural enemies of Pseudococcidae in different fruit plants cultivated in the semiarid region of Brazil. For this, mealybugs associated with roots, stems, leaves, and fruits of vine, pear, apple, persimmon, guava, and acerola trees were collected biweekly in 14 properties in the São Francisco Valley region, from July 2016 to June 2017. These mealybugs were properly separated for the removal of their predators and the emergence of parasitoids associated with them (Pseudococcidae). Coccophagus sp., Aenasius sp., Anagyrus kamali, Anagyrus sp. 1, Anagyrus sp. 2, Anagyrus sp. 3, Anagyrus sp. 4, Coccidoxenoides perminutus, Gyranusoidea indica, Leptomastix dactylopii, Prochiloneurus sp., Aprostocetus sp., and Signiphora sp. were identified as parasitoids and Diadiplosis multifila, Cryptolaemus montrouzieri, Tenuisvalvae notata, Cycloneda sanguinea, and Hippodamia convergens were identified as predators, in addition to unidentified species of Coccinellidae and Chrysopidae. Made available in DSpace on 2022-10-21T14:09:29Z (GMT). No. of bitstreams: 1 Biodiversity-of-Natural-Enemies-of-Pseudococcidae-in-the-Semiarid-Region-of-Brazil-2020.pdf: 210030 bytes, checksum: 1fbe49af51d5d23a9451c64e981f624a (MD5) Previous issue date: 2020

The objective of this work was to evaluate the lethal and sublethal toxicity of hexane and methanolic extracts from the leaves of Annona vepretorum (Annonaceae) on Tetranychus urticae (Acari: Tetranychidae). The methanolic extract toxicity was evaluated by Potter tower application (topical + residual effect) and by immersion of Canavalia ensiformis leaf disks in the extract solution (residual contact effect). The hexane extract toxicity was evaluated exclusively through residual contact effect. Sublethal effects of the methanolic extract were evaluated through LC50 on the females. Mite preference for feeding and oviposition was evaluated by multiple choice tests, between the control and the extract concentrations, using the hexane and methanolic extracts. Estimated LC50 for the methanolic extract was 10.96 mg mL-1 for the topic + residual effect and 22.07 mg mL-1 for the residual effect. Estimated LC50 for the hexane extract was 50.61 mg mL-1. The methanolic extract at the previously estimated CL50 interfered in the fecundity and longevity of females, differing significantly from the control treatment. In the multiple choice tests, for both extracts, mites showed a significant preference for the control, both for feeding and oviposition. Annona vepretorum has acaricide effect and constitutes a botanical source with great potential for controlling T. urticae. Resumo: O objetivo deste trabalho foi avaliar a toxicidade letal e subletal dos extratos hexânico e metanólico das folhas de Annona vepretorum (Annonaceae) sobre Tetranychus urticae (Acari: Tetranychidae). A toxicidade do extrato metanólico foi avaliada por meio da aplicação em torre de Potter (efeito tópico + residual) e por imersão de discos de folhas de Canavalia ensiformis na solução do extrato (efeito de contato residual). A toxicidade do extrato hexânico foi avaliada unicamente por meio do efeito de contato residual. Os efeitos subletais do extrato metanólico foram avaliados por meio da CL50 sobre as fêmeas. A preferência do ácaro por alimentação e oviposição foi avaliada por testes de múltipla escolha, entre o tratamento controle e as concentrações dos extratos, com os extratos hexânico e metanólico. A CL50 estimada do extrato metanólico foi de 10,96 mg mL-1 para o efeito tópico + residual e de 22,07 mg mL-1 para o efeito residual. A CL50 estimada para o extrato hexânico foi de 50,61 mg mL-1. O extrato metanólico na CL50 previamente estimada interferiu na fecundidade e na longevidade das fêmeas e diferiu significativamente do tratamento controle. Nos testes com múltipla escolha, para ambos os extratos, os ácaros apresentaram preferência significativa pelo controle, quanto à alimentação e à oviposição. Annona vepretorum apresenta efeito acaricida e constitui uma fonte botânica de grande potencial no controle de T. urticae.

From those of the mealybug family, the citrus mealybug, Planococcus citriRisso, 1813 (Hemiptera: Pseudococcidae) is frequently held responsible for various diseases occurring in vineyards. This is a first time report in Brazil, on the occurrence of a parasitoid controlling P. citri. In our search for the natural enemies of P. citri, bunches of grapes with the vine were collected every week for one month, in those regions where table grapes were produced, like Petrolina, Pernambuco, Brazil. In these samples, among the natural pest infestations Coccidoxenoides perminutusGirault, 1915 (Hymenoptera: Encyrtidae) was the only natural enemy species reported. In this research, we attempted to study the potential of parasitism as well as the strategies that this natural agent uses in pest control.

In vineyards, thrips are listed as pests in many countries in continental Europe and the United States, attacking fruits, flowers, leaves and buds. In Brazil, many species have been reported in vineyards. This work aimed to evaluate the best technique and sampling unit, and the number of samples required in a conventional plan for sampling thrips in a vineyard. The studies were carried out in areas of Vitis vinifera, cultivar Sugraone, without application of insecticides. An area of 2.240m2 was subjected to sample collection of leaves in different strata of 15 plants, and leaves on strata of branches for two subsequent years, totalizing 47 sampling dates. Furthermore, the sampling techniques of beating the inflorescence on a tray and whole inflorescence collection were also addressed. To calculate the sampling time, productive vineyards were used, with the varieties Sugraone and Thompson Seedless. Linear regressions of the relative densities as a function of absolute densities for thrips on branch per plant and leaves per branch were estimated. The technique of beating inflorescence on a tray was the one that best represented the results. The sampling unit that best represented the population was composed of one leaf collected from the median part of the branch. Thrips sampling should be conducted in 10 plants and 10 inflorescences per hectare to estimate the thrips population properly on plants and flowers, respectively. Index terms: Vitis vinifera. Thysanoptera. Sampling unit. Integrated pest management. TÉCNICA DE AMOSTRAGEM CONVENCIONALPARA TRIPES EM VIDEIRA RESUMO - Na cultura da videira, os tripes são mencionados como pragas em diversos países do continente Europeu e nos Estados Unidos, atacando frutos, flores, folhas e brotos. No Brasil, muitas espécies têm sido relatadas nesta cultura. Deste modo, o objetivo deste foi definir a melhor técnica, unidade amostral e o número de amostras exigidas em um plano convencional para a amostragem de tripes em uva. Os estudos foram realizados em áreas de Vitis vinifera, cultivar Sugraone, sem aplicação de inseticidas. Uma área de 2.240m2 foi submetida a coleta de amostras em diferentes estratos de folhas e ramos, em 15 plantas, durante dois anos, totalizando 47 datas de amostragem. Além disso, também foram abordadas as técnicas de amostragem de batida da inflorescência na bandeja e coleta da inflorescência. Para o cálculo do tempo de amostragem foram utilizados parreirais com as variedades Sugraone e Thompson Seedless. Foram estimadas equações de regressões lineares entre as densidades relativas e absolutas de tripes por folha e ramo. A técnica da batida da flor foi a mais adequada para a amostragem dos tripes em inflorescências. A unidade amostral composta por uma folha localizada no meio do ramo mediano da planta foi o plano de melhor representatividade. A amostragem deve ser realizada em 10 plantas e 10 inflorescências por hectare para detectar os tripes na folha e na flor da videira, respectivamente. Made available in DSpace on 2018-01-12T23:22:05Z (GMT). No. of bitstreams: 1 ArtigoTripes20171.pdf: 335576 bytes, checksum: b2f78d802ce8552faed48ad1d93bbb64 (MD5) Previous issue date: 2018-01-11

The Citrus mealybug Planococcus citri has a wide geographical distribution and has been described as a pest of economic importance in several crops. The present work determined the developmental and biological aspects of the Citrus mealybug in order to obtain information that may support the integrated pest management (IPM) of grapevine (Vitis vinifera L.) cv. Syrah in the Lower Basin of the Sao Francisco Valley region. The research was conducted at the Laboratory of Entomology of Embrapa Semiarid, Petrolina-PE, on leaves of grapevine kept in a controlled environment (25 ± 1°C, 60 ± 10% R. H. and a photoperiod of 12L:12D). The first two instars had higher mortality, indicating high susceptibility in these nymphal periods. The overall nymphal period of females and males is similar at 22.52 ± 0.46 and 23.5 ± 0.29 days, respectively, with viability of 39%. The adult longevity of females is nearly 30 times greater than that of males, indicating that females of P. citri are mainly responsible for damage and injury to grapevine. The sex ratio was 0.64, indicating that females make up the majority of the adult population of P. citri. We conclude that the species in question completes its lifecycle on leaves of grapevine and reaches the adult phase in a short time interval. Key words: Mealybugs, life cycle, grape.

The coccinellid Tenuisvalvae notata (Mulsant) (Coleoptera: Coccinellidae) has been observed recently in association with the striped mealybug Ferrisia virgata Cockerell (Hemiptera: Pseudococcidae) and the false cochineal scale Dactylopius opuntiae Cockerell (Hemiptera: Dactylopiidae) in the semiarid region of Pernambuco, Brazil. The latter species are important pests of cotton and prickly pear, respectively. In this study, we tested the two scale insects as prey for T. notata. In addition, eggs of Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) were tested as possible alternative prey for rearing T. notata. In this work, the survivorship, reproduction, and predation of T. notata were investigated. The coccinellid T. notata was able to complete development only on F. virgata with 83% larval and pupal viability. Females of T. notata fed F. virgata produced 7.6 eggs a day with an eclosion rate of 61.9%. No oviposition occurred while feeding on A. kuehniella eggs. The highest consumption rate of F. virgata occurred during the last larval instar. Our results support the use of T. notata as an agent for the biological control of F. virgata, a highly polyphagous pest worldwide.

O objetivo deste trabalho foi avaliar a eficiência da técnica de confusão sexual, com o feromônio sexual sintético composto (Z)-11-hexadecenal (Z11-16: Ald) a 1,8% e (Z)-13-octadecenal (Z13-18: Ald) a 1,8%, no controle da população de traça-dos-cachos, Cryptoblabes gnidiella (Lepidoptera: Pyralidae), em cultivares de videiras (Vitis vinifera) destinadas à produção de vinhos. Os experimentos foram realizados em duas localidades na região do Vale do São Francisco, em áreas comerciais de produção de uva para processamento, com as cultivares Cabernet Sauvignon, Petit Verdot, Tempranillo e Chenin Blanc. Os tratamentos avaliados foram os seguintes: confusão sexual com uso de liberadores Splat ("specialized pheromone and lure application technology"), aplicados com pistola manual a 500 pontos por hectare (2 g por ponto); e testemunha sem aplicação. O efeito da técnica sobre os adultos de C. gnidiella foi avaliado com uso de armadilha tipo Delta, iscada em um septo com 2 g de feromônio sintético da mesma formulação. Os danos nos cachos foram avaliados à colheita. O uso da técnica de confusão sexual reduziu a captura de adultos de C. gnidiella em mais de 59% na 'Tempranillo', 68% na 'Chenin Blanc', 80% na 'Cabernet Sauvignon' e 97% na 'Petit Verdot'. À época da colheita, os danos nos frutos foram reduzidos de 65 a 100% nas áreas tratadas. O feromônio sexual sintético é eficaz para reduzir o acasalamento de C. gnidiella em vinhedos, com o uso da técnica de confusão sexual. The objective of this work was to evaluate the efficiency of mating disruption technique, with the synthetic sex pheromone compound (Z)-11-hexadecenal (Z11-16: Ald) at 1.8% and (Z)-13-octadecenal (Z13-18: Ald) at 1.8%, for controlling the honeydew moth, Cryptoblabes gnidiella (Lepidoptera: Pyralidae), population in grape (Vitis vinifera) cultivars destined to wine production. The experiments were carried out in two locations in the region of São Francisco Valley, Brazil, in commercial production areas of grapes used for processing, with the cultivars Cabernet Sauvignon, Petit Verdot, Tempranillo, and Chenin Blanc. The evaluated treatments were: mating disruption using Splat (specialized pheromone and lure application technology) releasers, applied at 500 points per hectare (2 g per point); and a control without application. The effect of the technique was evaluated on adults of C. gnidiella using Delta type trap baited with 2 g of synthetic pheromone of the same formulation. The damage on grape clusters was evaluated at harvest. The use of mating disruption technique reduced the capture of adult C. gnidiella in more than 59% in 'Tempranillo', 68% in 'Chenin Blanc', 80% in 'Cabernet Sauvignon', and 97% in 'Petit Verdot'. At harvest, fruit damage was reduced from 65 to 100% in the treated areas. The synthetic sex pheromone is effective in reducing C. gnidiella mating in vineyards, using the mating disruption technique.

Thrips of the genus Frankliniella cause significant reduction on grape production. Little is known about its decision making approach in integrated pest management and information on thrips injuries to the vine is scarce, hindering the control of this pest. This study aimed to determine the species of thrips and injuries that cause damage to berries in seedless grapes clusters. The trial was conducted in an area cultivated with Vitis vinifera L., variety Thompson Seedless, using a randomized block design with five treatments and four replications. The treatments consisted of artificial infestation (zero, two, four and eight thrips per inflorescence), and treatment determined by the monitoring system of the grower. Each replication consisted of three plants with 10 inflorescences, which were artificially infested with thrips and covered with nonwoven fabric bags. During the cluster thinning, pre-harvest cleaning and harvest, the numbers of injuried berries and the berries with injuries were evaluated. The thrips species identified were: Frankliniella schultzei (Trybom), Frankliniella brevicaulis Hood, Frankliniella gemina Bagnall, Frankliniella gardeniae Moulton, and Frankliniella sp. A positive and significant correlation was observed between the number of injuries per fruit and the level of thrips infestation, obtained by the equation y = 2.55 + 48.54x (F= 59.98; P= 0.0001; r²= 0.51). The results suggest that the presence of a whitish halo around a small scar on fruit is associated with the presence of adult Frankliniella spp. Os tripes do gênero Frankliniella ocasionam perdas consideráveis à produção da videira. Informações sobre os danos ocasionados por esses insetos e a tomada de decisão em programas de manejo integrado em videira são escassos, dificultando o controle dessa praga. Neste trabalho, objetivou-se determinar as injúrias e as espécies de tripes que ocasionam danos em bagas de uva sem semente. O experimento foi conduzido em área comercial de Vitis vinifera L, cultivar Thompsom Seedless, em blocos ao acaso, com cinco tratamentos e quatro repetições. Os tratamentos foram: 0, 2, 4 e 8 tripes por inflorescência e o nível de controle do produtor determinado pelo monitoramento da área. Cada repetição foi constituída de três plantas com 10 inflorescências cada, as quais foram infestadas com tripes adultos e cobertas com saco de TNT TM (tecido não tecido). Durante o raleio, limpeza pré-colheita e colheita foram avaliados: o número de injúrias nas bagas e o número de bagas com injúrias. As espécies identificadas foram: Frankliniella schultzei (Trybom), Frankliniella brevicaulis Hood, Frankliniella gemina Bagnall, Frankliniella gardeniae Moulton e Frankliniella sp. Obteve-se correlação positiva e significativa entre o número de injúrias nas bagas e o nível de infestação de tripes: (y = 2,55 + 48,54x (F= 59,98; P= 0,0001; r²= 0,51). Os resultados sugerem que a presença de um halo esbranquiçado ao redor de uma pequena cicatriz, presente nas bagas, está associada à presença de adultos de Frankliniella spp.

Population growth and within-plant distribution of the striped mealybug Ferrisia virgata (Cockerell) (Hemiptera, Pseudococcidae) on cotton. The striped mealybug, Ferrisia virgata (Cockerell) (Hemiptera, Pseudococcidae), is a widely distributed and polyphagous pest species, which naturally occurs on cotton plants in Brazil. This study evaluated the establishment and population growth as well as the within-plant distribution of F. virgata on four cotton cultivars: CNPA 7H (white fibers), BRS Verde, BRS Safira, and BRS Rubi (colored fibers). The experiment was conducted in a complete randomized design with four treatments (cultivars) and 18 replications of each. Thus, cotton plants of each cultivar were infested with 100 newly hatched nymphs of F. virgata. The number of adult female mealybugs and the total number of mealybugs per plant were quantified, respectively, at 25 and 50 days after infestation. The developmental and pre-reproductive periods were also determined. Furthermore, we verified the distribution of F. virgata on the plant parts at 25 and 50 days after infestation. Ferrisia virgata showed similar growth of 412-fold in the four cotton cultivars studied. Also, the nymphs were spread on infested leaves; the secondgeneration nymphs were spread and established in all plant parts. Our results characterize F. virgata as having much potential as an important cotton pest in Brazil.

Mite pests are some of the major limiting factors affecting grape production in the world. Despite the economic importance of the grapevines and the damage to them caused by some of the phytophagous mites in northeast Brazil, little is known about the mite fauna associated with this crop. The present study aimed to identify the mite fauna associated with grapevine, to evaluate the fluctuation of the populations of the most frequent species of phytophagous mites and their associated predators over a 12-month period as well as their within-plant distribution. Considering all varieties sampled, Tetranychus urticae Koch and Oligonychus mangiferus (Rahman & Sapra) comprised 74% of phytophagous mites. Euseius citrifolius Denmark & Muma and Neoseiulus idaeus Denmark & Muma comprised more than 80% of Phytoseiidae mites. The population dynamics study was conducted in a vineyard of Sugraone and a vineyard of Itália Muscat varieties. In these fields, E. citrifolius occurred at low population levels throughout the year, whereas N. idaeus was found only when high densities of T. urticae were observed. Tetranychidae and Phytoseiidae showed the same pattern of within-plant distribution, being found in higher densities on basal and median leaves and rarely they were found on apical leaves.

Considered a generalist species among the coccinellids, the multicolored Asian lady beetle Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) feeds upon small arthropods and non-prey plant products, a practice which might enhance its ability to colonize various ecosystems but carries the potential to expose it to prey quality variation and insecticide use. Thus, we examined the effect of four different diets on the development, reproduction, and response to the insecticide lambda-cyhalothrin in this species. Three groups of larvae received laboratory-reared diets: (i) eggs of Anagasta kuehniella (Zeller) (Ak); (ii) eggs of Sitotroga cerealella (Olivier) (Sc); and (iii) eggs of A. kuehniella + S. cerealella at the proportion 1:1; and one group received wild-caught cotton aphids, Aphis gossypii Glover (Ag). Notwithstanding the generalist feeding behavior of H. axyridis, development and reproduction results were superior with diets of Ag or Ak compared with the diet combining 1:1 Ak + Sc or the diet of Sc eggs only. Furthermore, the Sc diet did not result in satisfactory development and reproduction. Despite this significant variation in biological responses, insecticide susceptibility studies using adults that had been reared on these diets showed no statistically significant differences in susceptibility to the lambda-cyhalothrin.

The coconut production system, in which the coconut mite Aceria guerreronis is considered a key pest, provides an interesting model for integration of biological and chemical control. In Brazil, the most promising biological control agent for the coconut mite is the phytoseiid predator Neoseiulus baraki. However, acaricides are widely used to control the coconut mite, although they frequently produce unsatisfactory results. In this study, we evaluated the simultaneous direct effect of dry residue contact and contaminated prey ingestion of the main acaricides used on coconut palms (i.e., abamectin, azadirachtin and fenpyroximate) on life-history traits of N. baraki and their offspring. These acaricides are registered, recommended and widely used against A. guerreronis in Brazil, and they were tested at their label rates. The offspring of the exposed predators was also evaluated by estimating the instantaneous rate of population increase (r i ). Abamectin compromised female performance, whereas fenpyroximate did not affect the exposed females (F0). Nonetheless, fenpyroximate strongly compromised the offspring (F1) net reproductive rate (R0), intrinsic rate of population growth (r i ), and doubling time (DT). In contrast, fenpyroximate did not have such effects on the 2nd generation (F2) of predators with acaricide-exposed grandparents. Azadirachtin did not affect the predators, suggesting that this acaricide can be used in association with biological control by this predatory species. In contrast, the use of abamectin and fenpyroximate is likely to lead to adverse consequences in the biological control of A. guerreronis using N. baraki.

In the Lower Middle Sao Francisco Valley, Tetranychus urticae Koch is controlled by the application of acaricides; however, the intensive use of these products in this region has caused control failures in the field. In the present study, concentration–response curves were constructed periodically to monitor the toxicity of abamectin to T. urticae in two vineyards over two years. Diagnostic concentrations of 1 mg and 9 mg of abamectin/L water were established based on the monitoring period to detect T. urticae resistance in different vineyards in the region. Concentration-response curves were obtained for abamectin, bifenthrin and carbosulfan for the populations considered resistant to abamectin. T. urticae were confined in arenas on cotyledonary leaf discs from jack bean (Canavalia ensiformis L.) that had been immersed in acaricide solution. Mite mortality was assessed after 48 h of exposure to the acaricides. The lethal concentration (LC) values varied over time in both of the vineyards studied, which was most likely a result of crop management. An additional 35 vineyards were sampled, and 20 additional populations were established. The results indicated that 45% of the populations exposed to the 9 mg/L abamectin diagnostic concentration experienced less than 80% mortality and were considered resistant to abamectin. The frequency of resistant mites ranged from 4.1% to 80.4%. The resistance ratio ranged from 2406-fold to 8272-fold compared to susceptible populations in the laboratory. Resistance to bifenthrin was also confirmed in the present study, though resistance to carbosulfan was not. No cross-resistance between abamectin and bifenthrin was observed though this requires further investigation.

Acaricides may interfere with a myriad of interactions among arthropods, particularly predator-prey interactions. The coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae), and its phytoseiid predator, Neoseiulus baraki (Athias-Henriot) (Acari: Phytoseiidae), provide an opportunity to explore such interference because the former is a key coconut pest species that requires both predation and acaricide application for its management. The objective of the present study was to assess the effect of the acaricides abamectin, azadirachtin and fenpyroximate on the functional response of N. baraki to A. guerreronis densities. The following prey densities were tested: 5, 10, 20, 40 and 80 preys. The type of functional response and prey handling time (Th) were not altered by the acaricides. However, the attack rate (a') was modified by abamectin and fenpyroximate, and the consumption peak was reduced by abamectin. All of the acaricides allowed for the maintenance of the predator in the field, but exposure to abamectin and fenpyroximate compromised prey consumption.

O objetivo deste trabalho foi avaliar a ocorrência de espécies de tripes em videira e a flutuação populacional, das espécies mais frequentes e abundantes, em diferentes fases fenológicas e sistemas de manejo. O experimento foi realizado em Petrolina, PE, em cinco parreirais - três da cultivar Sugraone (certificada, semiconvencional e convencional) e duas da cultivar Brasil (certificada e convencional). Foram coletadas folhas e inflorescências durante dois anos consecutivos (2008-2010), em 15 plantas. Foram realizadas análises de correlação entre as médias de infestação de tripes e os fatores meteorológicos temperatura, umidade relativa do ar e precipitação pluvial. O número médio de larvas e adultos de tripes foi comparado entre os sistemas de manejo e as fases fenológicas. Nas folhas, foram constatadas as espécies Heliothrips haemorrhoidalis, Retithrips syriacus, Selenothrips rubrocinctus, Frankliniella schultzei, Frankliniella sp. e Scolothrips sp., além de larvas de Aelothripidae. Nas inflorescências, foram identificadas apenas espécies de Thripidae, F. schultzei, F. brevicaulis, F. rodeos, F. gardeniae e Frankliniella sp. Não houve correlação de temperatura, umidade relativa e precipitação pluvial com o número médio de tripes. Existe um complexo de espécies de tripes na videira, e a fenologia da planta exerce influência na abundância desses insetos. The objective of this work was to evaluate the occurrence of thrips species and the population fluctuation, of the most frequent and abundant ones, in different management systems and phenological stages of grapevine. The experiment was carried out in Petrolina, PE, Brazil, in five vineyards - three with the cultivar Sugraone (certified, semi-conventional, and conventional) and two with the cultivar Brasil (certified and conventional). Leaves and flowers were collected during two subsequent years (2008-2010) from 15 plants. Correlation analyses were performed between the means of thrips infestation and the meteorological variables temperature, relative humidity, and rainfall. The average number of larvae and adult thrips was compared between the management systems and phenological stage. The thrips species found on leaves were: Heliothrips haemorrhoidalis, Retithrips syriacus, Selenothrips rubrocinctus, Frankliniella schultzei, Frankliniella sp., and Scolothrips sp., as well as nymphs of Aelothripidae. On flowers, only the Thripidae species was found: F. schultzei, F. brevicaulis, F. rodeos, F. gardenia, and Frankliniella sp. There was no correlation between temperature, relative air humidity, and rainfall with the average number of thrips. There is a thrips species complex on grapevine, and plant phenology affects the abundance of the insects.

RESUMO Planococcus citri é uma importante praga da videira, no submédio do Vale do São Francisco, e seu parasitismo por Coccidoxenoides perminutus, de ocorrência natural nesta região, foi estudado por meio da determinação dos parâmetros de resposta funcional. O experimento foi conduzido com ninfas de segundo ínstar dessa cochonilha, ofertadas nas densidades de 2, 4, 8, 14, 28, 40 e 50, empregando discos de folhas de videira (cv. Syrah). Fêmeas recém-emergidas e alimentadas do parasitoide foram confinadas com as ninfas por 24h. A taxa de parasitismo resultou em resposta funcional do tipo III, com os parâmetros tempo de manipulação (Th) e taxa de ataque (a’) de 0,9824h e 0,00718h-1, respectivamente. Observou-se correlação de 94,3% entre o parasitismo observado e o estimado pelo modelo de resposta funcional, com máximo de 27 e 24,44 ninfas parasitadas em 24h, respectivamente. A emergência de parasitoides de ninfas mumificadas variou entre 64 e 95%, em função das densidades estudadas. Os resultados mostraram que a resposta funcional de C. perminutus em ninfas de P. citri é do tipo III e que a taxa de emergência do parasitoide é influenciada pelas diferentes densidades de ninfas de P. citri oferecidas. Com base na resposta funcional determinada, C. perminutus apresenta potencial de controle da praga, contribuindo com informações para um futuro programa de controle biológico.

Worldwide, there remains a reliance on repeated chemical applications as a control strategy for the coconut mite, but these are impractical, not economical, and environmentally hazardous. In this study, the damage severity of Aceria guerreronis on coconut fruits was studied under different conditions to investigate the effects of bunch management on the amount of damage to newly produced bunches. The damage was evaluated using a diagrammatic scale under four different conditions: 1) plants with bunches removed; 2) bunches with the distal portion of the spikelet removed; 3) bunches sprayed monthly with abamectin (9 g a.i./ha); and 4) control plants. For each treatment, two fruits from bunches 1 to 6 (counted from the last open inflorescence) from 10 plants were randomly collected every month for 4 months. The removal of the distal portion of the spikelets had no effect on the damage level of new bunches but delayed the damage severity by ≈1 month. After the removal of all of the bunches, the damage severity was restored within 2 months to the newly produced bunches, whereas the chemical control with abamectin kept the A. guerreronis damage intensity at a low level. Thus, the removal of bunches or the distal portion of spikelets is not an effective practice for the control of A. guerreronis in areas with high levels of infestation.

Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae), também conhecida por traça-das-crucíferas, é uma praga importante de Brassicaceae, que pode ser encontrada em todos os continentes. A relação entre P. xylostella e as brassicáceas tem sido muito estudada uma vez que essa praga provoca grandes prejuízos em praticamente todas as regiões produtoras, no Brasil e no mundo. Também tem despertado grande interesse entre os pesquisadores o fato das brassicáceas utilizarem metabólicos secundários como defesa ao ataque de insetos generalistas, sendo que para especialistas, como P. xylostella, alguns desses metabólicos são incitantes de alimentação e oviposição. Na interação inseto-planta existem questões não compreendidas e que devem ser estudas, pois são diversas condições bióticas e abióticas que interagem nestes organismos, podendo promover alterações fisiológicas e nutricionais nas plantas, no desenvolvimento dos insetos e nas interações planta x herbívoro x parasitoide/predador. Assim, este trabalho objetivou estudar a influência de estresses hídricos em variedades de brássicas e seus reflexos nas plantas, no herbívoro especialista P. xylostella e no parasitoide Trichogramma pretiosum (Riley, 1879) (Hymenoptera: Trichogrammatidae). Foram efetuadas análises da composição química em folhas e da emissão de voláteis em três variedades (couve - Brassica oleracea var. acephala; brócolis - B. oleracea var. italica e repolho - B. oleracea var. capitata), em diferentes níveis de água no solo (50%, 70% e 100% da capacidade de campo), procurando-se determinar plantas comprovadamente com estresse hídrico. Também foi estudada a influência daquelas condições hídridas em parâmetros biológicos de desenvolvimento, de reprodução e de comportamento de P. xylostella, além da influência dos estresses hídricos na atratividade/repelência de T. pretiosum, parasitoide de ovos de P. xylostella. Com as variedades desenvolvidas nas três condições hídricas foram determinados: (a) nas plantas/folhas: taxa de peroxidação lipídica (MDA), porcentagem de proteína bruta na matéria seca, fibra em detergente neutro, fibra em detergente ácido, hemicelulose, lipídeos, teor de cera, proteínas insolúveis em detergente neutro, proteínas insolúveis em detergente ácido, proteínas disponíveis, matéria mineral, carboidratos totais e a emissão de voláteis; (b) com P. xylostella: consumo foliar, período larval, viabilidade larval, período pupal, viabilidade pupal, peso de pupas, razão sexual, ovos por fêmea, viabilidade de ovos, longevidade de fêmeas, longevidade de machos e tabela de vida de fertilidade, em laboratório e casa de vegetação, além da preferência para oviposição em testes com e sem chance de escolha; e (c) com T. pretiosum: teste de olfatometria com plantas nas três condições hídricas. Os resultados obtidos permitem concluir que: o déficit hídrico provoca estresse em couve, brócolis e repolho e em maior intensidade nas plantas cultivadas com menor quantidade de água disponível no solo; quantitativamente, a composição química das plantas (couve, brócolis e repolho) é alterada em função do estresse hídrico, principalmente quanto à proteína bruta e disponível, hemicelulose, lipídeos, proteínas ligadas à fibra em detergente ácido e neutro, matéria mineral e carboidratos totais; os parâmetros de desenvolvimento de P. xylostella são alterados, tanto em laboratório como em casa de vegetação, com as lagartas alimentando-se das plantas cultivadas nas diferentes condições hídricas de solo, refletindo significativamente na capacidade reprodutiva e na sobrevivência dos insetos; o estresse hídrico altera a emissão de voláteis em plantas de couve, em brócolis e repolho; a preferência de P. xylostella para oviposição, em testes com chance e sem chance, é influenciada pelo estresse hídrico em couve, brócolis e repolho; os testes de olfatometria mostram que o estresse hídrico influencia na escolha de T. pretiosum para oviposição, mais expressivamente em plantas com maiores índices de estresse hídrico Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae), also known as cruciferous moth, is an important pest of Brassicaceae, which can be found on all continents. The relationship between P. xylostella and brassicaceae has been much studied since this pest causes great damages in practically all the producing regions, in Brazil and in the world. It has also aroused great interest among researchers that brassicaceae use secondary metabolites as a defense against the attack of generalist insects, and for specialists, such as P. xylostella, some of these metabolites are prompting feeding and oviposition. In the interaction insect-plant there are questions not understood and that must be studied, because several biotic and abiotic conditions interact in these organisms, being able to promote physiological and nutritional changes in plants, in the development of insects and in the interactions plant x herbivore x parasitoid / predator. The objective of this work was to study the influence of water stresses on brassic varieties and their reflexes on plants, the P. xylostella herbivore and the Trichogramma pretiosum (Riley, 1879) (Hymenoptera: Trichogrammatidae) parasitoid. The chemical composition of leaves and the volatile emission were evaluated in three different varieties (kale - Brassica oleracea var. acephala; broccoli - B. oleracea var. italica and cabbage - B. oleracea var. capitata) in different soil water levels (50%, 70% and 100% of the field capacity), aiming to determine plants with water stress. The influence of these water conditions on biological development, reproduction and behavioral of P. xylostella, as well as the influence of water stress on the attractiveness / repellency of T. pretiosum parasitoid on P. xylostella eggs. The three varieties grown in the three water conditions and were determined: (a) in the plants / leaves: lipid peroxidation rate (MDA), percentage of crude protein in dry matter, neutral detergent fiber, acid detergent fiber, hemicellulose, lipids, wax, neutral detergent insoluble proteins, acid detergent insoluble proteins, available proteins, mineral matter, total carbohydrates and the emission of volatiles; (b) with P. xylostella: leaf consumption, larval period, larval viability, pupal period, pupal viability, pupal weight, sex ratio, eggs per female, egg viability, female longevity, male longevity and life table of fertility, laboratory and greenhouse, in addition to the preference for oviposition in tests with and without a choice; and (c) with T. pretiosum: tests of olfactometry with plants in the three water conditions. The results obtained allow us to conclude that: the water deficit causes stress in kale, broccoli and cabbage and in higher intensity in the plants cultivated with less amount of water available in the soil; quantitatively, the chemical composition of the plants (kale, broccoli and cabbage) is altered as a function of water stress, mainly as regards crude and available protein, hemicellulose, lipids, acid and neutral detergent fiber binding proteins, mineral matter and total carbohydrates; the development parameters of P. xylostella are altered, both in the laboratory and in the greenhouse, with caterpillars feeding on plants grown under different soil water conditions, significantly reflecting the reproductive capacity and survival of the insects; water stress changes the emission of volatiles in kale, broccoli and cabbage plants; the preference of P. xylostella for oviposition, in tests with chance and without chance, is influenced by water stress in kale, broccoli and cabbage; olfactometry tests show that water stress influences the choice of T. pretiosum for oviposition, more expressively in plants with higher rates of water stress