Mite fauna on transgenic soybean in an experimental station in western Bahia, Brazil

The aim of this study was to identify mite fauna associated with soybean crops and to report new species of the Monsoy 8349 IPRO variety in the municipality of Luís Eduardo Magalhães, western region of Bahia. Samplings were performed in an area with transgenic soybeans, subdivided into three treatments: T01, with no use of agricultural pesticides; T02, complete package of pesticides, except for acaricides; and T03, complete package of pesticides including acaricides. Twenty plants were selected per treatment at each sampling; one apical, one median, and one basal leaf were collected from each plant, totaling 60 leaves per treatment. A total of 1,292 mites were found, belonging to three families, five genera, and six species. The major phytophagous mite species found were Mononychellus planki McGregor and Tetranychus urticae Koch, while the major predatory mites found were Neoseiulus transversus Denmark & Muma and Euseius concordis Chant.

Phytophagous mites on genetically modified maize with Bacillus thuringiensis genes / Ácaros fitófagos em milho geneticamente modificado com genes de Bacillus thuringiensis

ABSTRACT: The study of non-target organisms such as mites, can provide information about the possible effects of transgenic maize cultivars on the arthropod community. This study aimed to evaluate the abundance of phytophagous mites in the area of Bt maize and evaluate the instantaneous population growth rate, and food preference of phytophagous mites on Bt maize. We registered the species occurrence and the number of adult mite individuals on four maize cultivars, one non-Bt 30F35, and three containing the proteins Cry1Ab (30F35 Yg), Cry1F (30F35 Hx) and Vip3a (Impacto Viptera). Cry proteins disrupt the midgut epithelium of insect pests. The food preference and instantaneous population growth rate (ri) were evaluated using the two-spotted spider mite Tetranychus urticae as model. The species Catarhinus tricholaenae and Aceria zeala were recorded. The Bt maize cultivars did not significantly affect the average number of C. tricholaenae and A. zeala mites compared to conventional cultivar. The population growth rates of T. urticae were similar for the different maize cultivars. T. urticae showed no preference between the leaf of Bt or conventional cultivars. Bt maize did not affect the abundance of species in phytophagous mite.

RESUMO: O estudo de organismos não-alvo, tais como ácaros, pode fornecer informações sobre os possíveis efeitos de cultivares de milho transgênico na comunidade de artrópodos. Este estudo teve como objetivo avaliar a abundância de ácaros fitófagos na área de milho Bt e avaliar a taxa de crescimento populacional instantânea e preferência alimentar de ácaros fitófagos em milho Bt. Registramos a ocorrência de espécies e número de indivíduos adultos de ácaros em quatro cultivares de milho, um não-Bt 30F35, e três contendo a proteína Cry1Ab (30F35 Yg), Cry1F (30F35 Hx) e VIP3A (Impacto Viptera). A preferência alimentar e taxa instantânea de crescimento populacional foram avaliadas utilizando fêmeas adultas do ácaro-rajado Tetranychus urticae. As espécies Catarhinus tricholaenae e Aceria zeala foram registradas. As cultivares de milho Bt não afetaram significativamente o número médio de ácaros C. tricholaenae e A. zeala em relação ao cultivar convencional. As taxas de crescimento populacional de T. urticae foram similares para os diferentes cultivares. T. urticae não mostrou preferência entre a folha de milho Bt ou cultivares convencionais. Sugere-se, então, que o milho Bt não afeta a abundância de espécies, preferência alimentar e taxa de crescimento de ácaros fitófagos.

Control of Tetranychus urticae Koch by extracts of three essential oils of chamomile, marjoram and Eucalyptus

<p><b>OBJECTIVE</b>To evaluate the acaricidal activity of extracts of three essential oils of chamomile, marjoram and Eucalyptus against Tetranychus urticae (T. urticae) Koch.</p><p><b>METHODS</b>Extracts of three essential oils of chamomile, marjoram and Eucalyptus with different concentrations (0.5%, 1.0%, 2.0%, 3.0% and 4.0%) were used to control T. urticae Koch.</p><p><b>RESULTS</b>The results showed that chamomile (Chamomilla recutita) represented the most potent efficient acaricidal agent against Tetranychus followed by marjoram (Marjorana hortensis) and Eucalyptus. The LC50 values of chamomile, marjoram and Eucalyptus for adults were 0.65, 1.84 and 2.18, respectively and for eggs 1.17, 6.26 and 7.33, respectively. Activities of enzymes including glutathione-S-transferase, esterase (α-esterase and β-esterase) and alkaline phosphatase in susceptible mites were determined and activities of enzymes involved in the resistance of acaricides were proved. Protease enzyme was significantly decreased at LC50 of both chamomile and marjoram compared with positive control. Gas chromatography-mass spectrometer (GC-MS) proved that the major compositions of Chamomilla recutita are α-bisabolol oxide A (35.251%), and trans-β-farersene (7.758%), while the main components of Marjorana hortensis are terpinene-4-ol (23.860%), p-cymene (23.404%) and sabinene (10.904%).</p><p><b>CONCLUSIONS</b>It can be concluded that extracts of three essential oils of chamomile, marjoram and Eucalyptus possess acaricidal activity against T. urticae.</p>

Ácaros (Arachnida: Acari) associados a plantas ornamentais tropicais na região litoral sul da Bahia / Mites (Arachnida: Acari) associated with tropical ornamental plants in the southern coastal region of Bahia, Brazil

Em razão da expansão do agronegócio de flores tropicais na região Litoral Sul da Bahia e da inexistência de estudos com ácaros associados a essas culturas na região foram realizadas coletas no período de setembro de 2006 a junho de 2007 em 34 espécies/cultivares de plantas ornamentais tropicais das famílias Costaceae, Heliconiaceae, Musaceae e Zingiberaceae de onze propriedades localizadas em seis municípios (13º 21' a 14º 58' de latitude Sul e 39º 04' a 39º 27' de longitude Oeste), com o objetivo de se determinar a composição de grupos funcionais nos cultivos analisando-se a comunidade no nível de família por meio de índices faunísticos. Os ácaros foram coletados, mensalmente, em folhas e inflorescências. Foram registradas 22 famílias. Mais da metade dos ácaros pertenceu a famílias predominantemente predadoras, com destaque para os fitoseídeos. Com base em índices faunísticos, as famílias Phytoseiidae e Tetranychidae atingiram os índices máximos de dominância, abundância, frequência e constância. Tetraniquídeos (Tetranychus aff. abacae Baker & Pritchard) foram registrados em Alpinia purpurata (Viell.) Schum, Etlingera elatior (Jack) R. M. Smith, Musa coccinea H.C. Andrews, Strelitzia reginae Aiton, Zingiber spectabilis Griffith, Heliconia latispatha Benth., Heliconia rivularis L. Emygd. & E. Santos, Heliconia rostrata Ruiz & Pavon, Heliconia wagneriana Petersen e nos cultivares de helicônias 'Nappi Yellow', 'Jacquinii', 'She', 'Golden Torch', 'Red Opal', 'Alan Carle', 'Fire Bird' e 'Nappi Red'. As espécies/cultivares com maior número de famílias de ácaros foram H. latispatha. H. rostrata. M. coccinea, 'Fire Bird', E. elatior 'Vermelha', Z. spectabilis. E. elatior 'Rosa', A. purpurata 'Vermelha' e helicônias 'Alan Carle', 'Sassy' e 'She'. Não foram detectados nas plantas danos que causassem prejuízos econômicos aos produtores. As pequenas populações de fitófagos sugerem um eficiente controle natural por predadores, patógenos ou outros fatores.

Due to the expansion of the tropical flower agribusiness in the southern coastal region of Bahia State, Brazil, and the lack of studies on mites associated to these cultures in the region, mite surveys were conducted from September 2006 to June 2007 in 34 species/cultivars of ornamental plants of the families Costaceae, Heliconiaceae, Musaceae and Zingiberaceae on 11 properties located in 6 counties (13º 21' to 14º 58' of south latitude and 39º 04' to 39º 27' of west longitude) with the aim of determining the composition of functional groups in the field through the analysis of the community at the family level using faunistic indexes. Mites were collected monthly from leaves and inflorescences. Twenty-two families were recorded. More than half of the mites pertained to predominantly predatory families, mainly to phytoseiids. Based on faunistic indexes, the families Phytoseiidae and Tetranychidae showed the maximum indexes of dominance, abundance, frequency and constancy. Tetranychids (Tetranychus aff. abacae Baker & Pritchard) were reported on Alpinia purpurata (Viell.) Schum, Etlingera elatior (Jack) R. M. Smith, Musa coccinea H.C. Andrews, Strelitzia reginae Aiton, Zingiber spectabilis Griffith, Heliconia latispatha Benth., Heliconia rivularis L. Emygd. & E. Santos, Heliconia rostrata Ruiz & Pavon, Heliconia wagneriana Petersen and on the cultivars of heliconia 'Nappi Yellow,' 'Jacquinii,' 'She,' 'Golden Torch,' 'Red Opal,' 'Alan Carle,' 'Fire Bird' and 'Nappi Red.' The species/cultivars with the largest number of mite families were H. latispatha. H. rostrata. M. coccinea, 'Fire Bird,' E. elatior 'Vermelha,' Z. spectabilis. E. elatior 'Rosa,' A. purpurata 'Vermelha' and heliconias 'Alan Carle,' 'Sassy' and 'She.' No mite-induced economic losses on tropical flower cultures were observed. The low population levels of phytophagous mites suggest an efficient natural control by predators, pathogens and other factors.

Phytophagous mites (Tetranychoidea: Tetranychidae, Tenuipalpidae) from natural vegetations in Lara, Venezuela / Ácaros fitófagos (Tetranychoidea: Tetranychidae, Tenuipalpidae) de vegetación natural en Lara, Venezuela

Phytophagous mites from natural vegetation have been scarcely studied in Venezuela. Surveys were carried out from March 2007 to November 2008 to determine diversity of phytophagous mites inhabiting in different plant taxa in Iribarren, Jiménez, Palavecino, Morán and Crespo municipalities from Lara state, Venezuela. In each sampling site, a 500 m- transect was established and the most frequent plant species were sampled. In field, 15 leaves were examined for mite presence by using hand lens. In laboratory, plant material was examined under magnification and mite morpho-species belonging to tetranychid and tenuipalpid were picked up. A total of two tenuipalpid species and eight tetranychid species were identified. Tenuipalpid mites identified were Brevipalpus phoenicis (Geijskes) on Cassia siamea (Caesalpinaceae), Capparis linearis (Capparidaceae), Spathodea campanulata (Bignoniaceae), Randia sp. (Rubiaceae), Melicoccus bijugatus (Sapindaceae) and Tenuipalpus sp. was collected from Spondias mombin (Anacardiaceae). On the other hand, tetranychid included Tetranychus urticae Koch on Terminalia catappa (Combretaceae), Euphorbia pulcherrima (Euphorbiaceae) and Enterolobium cyclocarpum (Mimosaceae). Tetranychus cinnabarinus (Boisduval) on Lycopersicon sp. (Solanaceae), Ipomoea sp., Convolvulus sp. (Convolvulaceae) and Leonotis nepetifolia (Lamiaceae). Tetranychus desertorum Banks on Parthenium hysterophorus (Asteraceae). Eutetranychus banksi (McGregor) on C. siamea, Chlorophora tinctoria (Moraceae), Dalechampia sp. (Euphobiaceae) and Malpighia glabra (Malpighiaceae). Eotetranychus cf. willamettei on Sterculia apetala (Sterculiaceae). Oligonychus biharensis (Hirst) on Clitoria sp. (Papilionaceae) and Ziziphus cyclocardia (Rhamnaceae). Oligonychus sp. on S. campanulata and Neotetranychus gloriosus Estebanes & Baker on Croton sp. (Euphorbiaceae). In this study, B. phoenicis is recorded for the first time on C. siamea, S. campanulata, Randia...

Los ácaros fitófagos de especies vegetales no cultivadas han sido poco estudiados en Venezuela. Desde marzo 2007 hasta noviembre del 2008, se realizaron muestreos para determinar la diversidad de ácaros fitófagos habitantes de diferentes taxa vegetales en los municipios Iribarren, Jiménez, Palavecino, Morán y Crespo en el estado Lara, Venezuela. En cada sitio de muestreo, se trazó una transecta de 500 m de longitud donde fueron muestreadas las plantas más frecuentes. En el campo, 15 hojas fueron examinadas para determinar la presencia de ácaros con el uso de una lupa de mano. En el laboratorio, el material vegetal fue examinado bajo aumento de una lupa estereoscopio para seleccionar las morfo-especies de tetraníquidos y tenuipálpidos. Se identificaron dos especies de Tenuipalpidae y ocho de Tetranychidae. Los ácaros tenuipálpidos identificados fueron Brevipalpus phoenicis (Geijskes) sobre Cassia siamea (Caesalpinaceae), Capparis linearis (Capparidaceae), Spathodea campanulata (Bignoniaceae), Randia sp. (Rubiaceae), Melicoccus bijugatus (Sapindaceae) y Tenuipalpus sp. fue colectado sobre Spondias mombin (Anacardiaceae). Por otra parte, las especies de tetraníquidos incluyeron a Tetranychus urticae Koch sobre Terminalia catappa (Combretaceae), Euphorbia pulcherrima (Euphorbiaceae) y Enterolobium cyclocarpum (Mimosaceae). Tetranychus cinnabarinus (Boisduval) sobre Lycopersicon sp. (Solanaceae), Ipomoea sp., Convolvulus sp. (Convolvulaceae) y Leonotis nepetifolia (Lamiaceae). Tetranychus desertorum Banks sobre Parthenium hysterophorus (Asteraceae). Eutetranychus banksi (McGregor) sobre C. siamea, Chlorophora tinctoria (Moraceae), Dalechampia sp. (Euphorbiaceae) y Malpighia glabra (Malpighiaceae). Eotetranychus cf. willamettei sobre Sterculia apetala (Sterculiaceae), Oligonychus biharensis (Hirst) sobre Clitoria sp. (Papilionaceae) y Ziziphus cyclocardia (Rhamnaceae). Oligonychus sp. sobre S. campanulata y Neotetranychus gloriosus Estebanes...

Association Between Sensitization to Outdoor Spider Mites and Clinical Manifestations of Asthma and Rhinitis in the General Population of Adults

It has been demonstrated that spider mites such as the two-spotted spider mite (Tetranychus urticae) are important allergens for fruit farmers. A total of 2,467 adults (795 metropolitan urban, 788 non-metropolitan urban, and 884 rural subjects) were enrolled. They responded to the questionnaire, and underwent methacholine bronchial provocation tests as well as skin prick tests to locally common aeroallergens including the two-spotted spider mite. The prevalences of asthma and rhinitis as reported on the questionnaire were 7.8% and 16.4% of adults aged 20-35, 9.4% and 24.7% of those 36-50, and 17.7% and 21.7% of those older than 50, respectively. Among the older group, the two-spotted spider mite was the most common sensitizing allergen, although it was second of that of house dust mites among the other two age groups. Sensitization to the two-spotted spider mite was significantly associated with the prevalence of asthma and rhinitis among the younger age group, and associated with the prevalence of rhinitis among the older age group. The twospotted spider mite might be a common sensitizing allergen in the general population of adults, and sensitization to this mite may play a role in the manifestation of asthma and rhinitis symptoms during adulthood.