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1.
Plant Biol (Stuttg) ; 25(1): 208-214, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36184888

RESUMEN

Galls display a multiplicity of traits, including colours, which are driven by pigment accumulation. Their conspicuousness has attracted researchers' attention and several hypotheses have been raised. However, plants themselves vary intra-specifically, including in their pigment concentrations. As galls are a result of host tissue development, colours may be a by-product of the host's own traits, being more conspicuous simply because the sites where galls develop already have the predisposition to accumulate more pigment. Here, we call this the host variation hypothesis. We test this hypothesis using the system of galls induced by Palaeomystella oligophaga on Macairea radula host plant. Using spectrophotometry, we calculated the Anthocyanin Reflectance Index (ARI) of gall projections, which are responsible for their characteristic colours. We tested the influence of occupant identity (galling insect or any natural enemy), gall volume, parenchyma thickness, height from the ground, ARI of leaf, ARI of gall surface and ARI of the respective stem. We corroborated the host variation hypothesis since the anthocyanin content in stems and in galls' projections were positively related. Moreover, anthocyanin in galls' projections was positively related to anthocyanin in the gall surface and negatively related to gall volume and parenchyma thickness. This shows that, besides the host specificities, galls' own traits may also be responsible for pigment accumulation, influencing their colours. In this study, using colour as an example, we show that although galls tend to be considered complex expressions of galling insects' stimuli, their traits may be simply influenced by previous and specific attributes of the host organs.


Asunto(s)
Melastomataceae , Mariposas Nocturnas , Animales , Tumores de Planta , Antocianinas , Plantas , Insectos , Interacciones Huésped-Parásitos
2.
Environ Entomol ; 51(6): 1166-1171, 2022 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-36178318

RESUMEN

The phylloxera Daktulosphaira vitifoliae (Fitch) is considered the main pest in vine crops in the world. One of the alternatives for pest management is the use of resistant rootstocks. In the present study, 14 vine genotypes comprised of 6 canopy cultivars (Bordô, Isabel, BRS Lorena, Cabernet Sauvignon, Magnólia, and Chardonnay), 4 commercial rootstocks (Paulsen 1103, SO4, IAC 766, and IAC 572), and 4 promising rootstocks for pest management (1111-21, 548-44, 548-15, and IBCA-125) were evaluated for resistance to infestation the of root form of pest. For each genotype, the number of eggs, nymphs, and adults present in the roots were evaluated at 15, 20, 25, 30, and 35 d after egg infestation. In addition, the feeding place (lignified or nonlignified root), the presence or absence of tuberosities and nodosities, and the total fecundity of females were evaluated. The highest survival rates of nymphs and adults were observed in Cabernet Sauvignon, BRS Lorena, Chardonnay, and IBCA-25 in lignified roots, with the formation of tuberosities characterizing the materials as susceptible. In contrast, SO4, Paulsen 1103, IAC 572, IAC 766, 548-44, 548-15, Magnólia, and 1111-21 provided the least nymph and adult survival over time in nonlignified roots present in the nodosities, characterizing the materials as resistant. In addition, the lowest fecundity was observed in the roots of Magnólia (16 eggs). According to the results, it was verified that the cultivar Magnolia and the selections 548-15 and 1111-21 present reduced infestation and survival of nymphs of D. vitifoliae in the roots. This fact demonstrates the potential of the materials to be used as new resistant rootstocks or sources of insect resistance.


Asunto(s)
Hemípteros , Vitis , Femenino , Animales , Hemípteros/genética , Brasil , Genotipo , Control de Plagas
3.
Environ Entomol ; 51(1): 210-215, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-34788395

RESUMEN

The grapevine phylloxera Daktulosphaira vitifoliae (Fitch) is the pest insect of greatest importance in grapevine. The objective of study was to evaluate the occurrence of overwintering eggs in seedlings of 'Paulsen 1103' (Vitis berlandieri × Vitis rupestris) and evaluate the biology and fertility life table of D. vitifoliae on five grape cultivars: 'Bordô' (Vitis labrusca), 'Cabernet Sauvignon' (Vitis vinifera), 'BRS Lorena' (Vitis vinifera × Seyval [Seibell 5656-Rayon d'Or]), 'Magnolia' (Vitis rotundifolia), and 'Paulsen 1103'. In the field, overwintering eggs were found to be present in 78% of 'Paulsen 1103' seedlings, on the trunk of the seedlings. In the laboratory, phylloxera was found to complete the biological cycle (egg to adult) in roots of 'BRS Lorena', 'Bordô', and 'Cabernet Sauvignon'. Nymphs did not complete development on roots of 'Paulsen 1103' and 'Magnolia', with 100% first instar mortality. Adult females feeding on 'Bordô' roots showed the lowest total fecundity (20.9 eggs per female), differing from insects feeding on 'Cabernet Sauvignon' roots (207.8 eggs per female). Based on the fertility life table, roots of 'Cabernet Sauvignon' provided the best reproduction rate (Ro = 219), intrinsic rate of increase (rm = 0.197 d) and time between generations (T = 21.5 d). The presence of overwintering eggs on the trunk of the rootstock 'Paulsen 1103' may promote the survival and dispersal of the insect. Lignified roots of the rootstock 'Paulsen 1103' and the cultivar 'Magnolia' do not allow the development of D. vitifoliae, with 'Cabernet Sauvignon' being the most suitable for the development of the insect.


Asunto(s)
Hemípteros , Vitis , Animales , Biología , Brasil , Femenino , Fertilidad , Tablas de Vida , Reproducción
4.
Rev. biol. trop ; 69(1)2021.
Artículo en Inglés | LILACS, SaludCR | ID: biblio-1507824

RESUMEN

Introduction: The enemy hypothesis postulates that gall traits protect galling insects against natural enemies. Galls show a huge range of sizes, colors and ornaments, which vary even intraspecifically. However, galling insects are targets of various organisms that attack them directly or indirectly. In this context, to consider only one gall trait to investigate gall structure acting against only one guild of enemies can conceal an understanding of the community-level interactions. Objective: Herein, we take these ideas into consideration to investigate the conspicuous galls induced by Palaeomystella oligophaga Becker and Adamski 2008 (Lepidoptera) on Macairea radula (Bonpl.) (Melastomataceae) as a model system. We characterize this system through categorization of the different enemy guilds present in the community. We identified them to the lowest taxonomic level possible and determined the kind of interaction responsible for galling insects' deaths. Considering the enemy hypothesis and the selection of secondary characteristics, we also aimed to determine which of the multiple gall traits influence the survival success of galling insects in a multi-enemy context. Methods: We inspected galls and characterized the enemy guilds affecting the galling insect and the mortality rates produced by each one of them. Next, we tested whether the distinct gall traits measured (parenchyma thickness, color, projections) promote galling insect survival with respect to each enemy. Results: The mortality induced by indirect enemies (organisms that interact with gall tissues and can interact secondarily with galling insect) was 47.3 %, being higher than that caused by parasitoids and predators (31.5 %). Despite the gall's structural complexity, live galling insects showed the smallest occurrence (21.2 %). Parenchyma thickness was negatively related to Calliephialtes parasitoids, Gelechiidae cecidophages and predation signals. Conclusions: We demonstrated that the attacks to gall tissues by the cecidophages represented the highest threat to P. oligophaga survival, being higher than the mortality caused by direct enemies. That is, the gall traits were not as efficient as supposed to protect the galling insect from the attack of natural enemies. Nevertheless, we also demonstrated that parenchyma thickness can be negatively related to some organisms, especially direct enemies. Other traits hypothesized as defensive (e.g. projections, coloration) may simply play no role.


Introducción: La hipótesis del enemigo postula que las características de la agalla protegen al agallero contra los enemigos naturales. Las agallas muestran una gran variedad de tamaños, colores y adornos, que varían incluso de forma intraespecífica. Sin embargo, los agalleros son objetivos de varios organismos que los atacan directa o indirectamente. En este contexto, considerar solo una característica para investigar la estructura de la agalla actúando contra un solo gremio de enemigos puede ocultar una comprensión de las interacciones a nivel comunitario. Objetivos: Para investigar las ideas presentadas usamos las agallas conspicuas inducidas por Palaeomystella oligophaga Becker y Adamski 2008 (Lepidoptera) en Macairea radula (Bonpl.) (Meslastomataceae) como sistema modelo. Describimos este sistema a través de la categorización de los diferentes gremios enemigos presentes en la comunidad. Los identificamos al nivel taxonómico más bajo posible y determinamos el tipo de interacción responsable de la muerte de los agalleros. Teniendo en cuenta la hipótesis del enemigo y la selección de características secundarias, también buscamos determinar cuáles de las múltiples caracteristicas de la agalla influyen en el éxito de supervivencia de los agalleros en un contexto de enemigos múltiples. Métodos: Inspeccionamos las agallas y caracterizamos los gremios enemigos que afectan al agallero y las tasas de mortalidad producidas por cada uno de ellos. Luego, probamos si las distintas caracteristicas de las agallas medidas (grosor del parénquima, color, proyecciones) promueven la supervivencia de los agalleros con respecto a cada enemigo. Resultados: La mortalidad indirecta inducida por los cecidofagos fue del 47.3 %, superior a la causada por los parasitoides y los depredadores (31.5 %). Apesar de la complejidad estructural de la agalla, los agalleros vivos mostraron la menor presencia (21.2 %). El grosor del parénquima se relacionó negativamente con los parasitoides de Calliephialtes, los cecidófagos de Gelechiidae y la depredación. Conclusiones: Demostramos que los ataques a los tejidos biliares por cecidófagos representaron la mayor amenaza para la supervivencia de P. oligophaga. Esto es interesante porque, de acuerdo con la hipótesis del enemigo, la estructura de las agallas debería proporcionar protección para los insectos agalleros en lugar de atraer a los insectos que se alimentan de la agalla misma. Sin embargo, también demostramos que el grosor del parénquima puede estar relacionado negativamente con algunos organismos, especialmente los enemigos directos. Otras caracteristicas hipotéticas como defensivas (por ejemplo, proyecciones, coloración) pueden simplemente no desempeñar ningún papel.


Asunto(s)
Animales , Conducta Predatoria , Insectos , Lepidópteros/crecimiento & desarrollo , Antocianinas/análisis
5.
Plant Biol (Stuttg) ; 22(5): 917-923, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32485039

RESUMEN

Although the production of extranuptial nectar is a common strategy of indirect defence against herbivores among tropical plants, the presence of extranuptial nectaries in reproductive structures is rare, especially in ant-plants. This is because the presence of ants in reproductive organs can generate conflicts between the partners, as ants can inhibit the activity of pollinators or even castrate their host plants. Here we evaluate the hypothesis that the ant-plant Miconia tococa produces nectar in its petals which attracts ants and affects fruit set. Floral buds were analysed using anatomical and histochemical techniques. The frequency and behaviour of floral visitors were recorded in field observations. Finally, an ant exclusion experiment was conducted to evaluate the effect of ant presence on fruit production. The petals of M. tococa have a secretory epidermis that produces sugary compounds. Nectar production occurred during the floral bud stage and attracted 17 species of non-obligate ants (i.e. have a facultative association with ant-plants). Ants foraged only on floral buds, and thus did not affect the activity of pollinators in the neighbouring open flowers. The presence of ants in the inflorescences increased fruit production by 15%. To our knowledge, the production of extranuptial nectar in the reproductive structures of a myrmecophyte is very rare, with few records in the literature. Although studies show conflicts between the partners in the ant-plant interaction, ants that forage on M. tococa floral buds protect the plant against floral herbivores without affecting bee pollination.


Asunto(s)
Hormigas , Flores , Melastomataceae , Néctar de las Plantas , Simbiosis , Animales , Flores/anatomía & histología , Melastomataceae/anatomía & histología , Melastomataceae/fisiología , Polinización
6.
Plant Biol (Stuttg) ; 22(5): 761-768, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32544284

RESUMEN

The partial or complete loss of chlorophylls, or albinism, is a rare phenomenon in plants. In the present study, we provide the first report of the occurrence in albino Delonix regia seedlings and describe the morpho-physiological changes associated with albinism. Wild-type (WT) and albino seedlings were characterized. Leaflets samples were processed following common procedures for analysis with light, scanning and transmission electron microscopy. The chlorophyll a fluorescence parameters and the carbohydrate, lipid and soluble protein content were also determined in leaf and cotyledon samples of both albino and WT seedlings. Albino seedlings showed reduced growth. They also had lower chlorophyll and protein content in foliar tissues than WT seedlings, in addition to lower concentrations of lipids and carbohydrates stored in cotyledons. The chloroplasts of albino seedlings were poorly developed, with an undefined internal membrane system and the presence of plastoglobules. Wild-type seedlings had a uniseriate and hypoestomatic epidermis. The mesophyll was dorsiventral, consisting of a layer of palisade parenchyma and two to four layers of spongy parenchyma. In albino seedlings, the spongy parenchyma was compact, with few intercellular spaces, and the thickness of the mesophyll was larger, resulting in increased thickness of the leaf blade. Albino seedlings had higher stomatal density and number of pavement cells, although the stomata had smaller dimensions. In addition to the partial loss of chlorophylls, albino D. regia showed changes at physiological and structural levels, demonstrating the crucial nature of photosynthetic pigments during the development and differentiation of plant leaf tissues/cells.


Asunto(s)
Clorofila , Fabaceae , Plantones , Clorofila/genética , Clorofila/metabolismo , Cloroplastos/metabolismo , Fabaceae/anatomía & histología , Fabaceae/fisiología , Fotosíntesis/fisiología , Hojas de la Planta/fisiología , Plantones/fisiología
7.
Neotrop Entomol ; 49(2): 292-301, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31907799

RESUMEN

The present study evaluated the lethal toxicity and oviposition deterrence of ethanolic extracts of Annona mucosa Jacq., Annona muricata L., and Annona sylvatica A. St.-Hil on Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) compared with those of a limonoid-based bioinsecticide (Azamax™ 1.2 EC-azadiractin +3-tigloyl-azadiractol) and a synthetic spinosyn-based insecticide (Delegate™ 250 WG-spinetoram). In addition, the efficacy of the selected toxic bait formulations was evaluated by mixing them with food attractants (Anamed™, 3% Biofruit and 7% sugarcane molasses). In the topical application and ingestion bioassays (2000 mg L-1), the aqueous emulsion of the A. mucosa extract caused greater than 80% mortality of A. fraterculus adults in a similar manner to the spinosyn-based synthetic insecticide. Concentration-response curves were performed for the most promising treatments and showed an activity level dependent on the mode of contamination, exposure time, and applied concentration. In bioassays with and without choice, the A. mucosa (77%), A. muricata (51%), A. sylvatica (60%), Azamax™ (74%), and Delegate™ 250 WG (100%) significantly reduced the number of punctures and galleries in grape berries. In combination with the food attractants Anamed™, 3% Biofruit, and 7% sugarcane molasses, the emulsion of the A. mucosa extract had a residual effect similar to that of the spinetoram insecticide, with a mortality rate of over 80% of A. fraterculus adults up to 14 days after application (DAA) in the absence of rain. Thus, acetogenin-rich formulations, especially from A. mucosa seeds, are useful alternatives for the integrated management of A. fraterculus in agricultural orchards.


Asunto(s)
Acetogeninas/química , Annona/química , Insecticidas/administración & dosificación , Extractos Vegetales/química , Tephritidae , Animales , Femenino , Oviposición , Pruebas de Toxicidad
8.
Vaccine ; 37(43): 6415-6425, 2019 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-31519445

RESUMEN

Hepatitis B virus causes acute and chronic infections in millions of people worldwide and, since 1982, a vaccine with 95% effectiveness has been available for immunization. The main component of the recombinant hepatitis B vaccine is the surface antigen protein (HBsAg). In this work, the effect of pH, ionic strength and temperature on the native state of the HBsAg antigen were studied by a combination of biophysical methods that included small angle X-ray scattering, synchrotron radiation circular dichroism, fluorescence and surface plasmon resonance spectroscopies, as well as in vivo and in vitro potency assays. The native conformation, morphology, radius of gyration, and antigenic properties of the HBsAg antigen demonstrate high stability to pH treatment, especially in the pH range employed in all stages of HBsAg vaccine production and storage. The HBsAg protein presents thermal melting point close to 56 °C, reaching a more unfolded state after crossing this point, but it only experiences loss of vaccine potency and antigenic properties at 100 °C. Interestingly, a 6-month storage period does not affect vaccine stability, and the results are similar when the protein is kept under refrigerated conditions or at room temperature (20 °C). At frozen temperatures, large aggregates (>200 nm) are formed and possibly cause loss of HBsAg content, but that does not affect the in vivo assay. Furthermore, HBsAg has a well-ordered secondary structure content that is not affected when the protein is formulated with silica SBA-15, targeting the oral delivery of the vaccine. The combined results from all the characterization techniques employed in this study showed the high stability of the antigen at different storage temperature and extreme values of pH. These findings are important for considering the delivery of HBsAg to the immune system via an oral vaccine.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/química , Antígenos de Superficie de la Hepatitis B/inmunología , Estabilidad Proteica , Temperatura , Animales , Dicroismo Circular , Femenino , Fluorescencia , Vacunas contra Hepatitis B/química , Vacunas contra Hepatitis B/inmunología , Virus de la Hepatitis B/química , Concentración de Iones de Hidrógeno , Inmunogenicidad Vacunal , Ratones , Ratones Endogámicos BALB C , Desnaturalización Proteica , Dióxido de Silicio/química , Resonancia por Plasmón de Superficie , Potencia de la Vacuna
9.
Neotrop Entomol ; 48(5): 866-872, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31372828

RESUMEN

The Hindustan citrus mite, Schizotetranychus hindustanicus Hirst (Acari: Tetranychidae), is a quarantine pest present in the state of Roraima, Brazil. This mite, which was described in India in 1924, was reported in 2002 in Venezuela and spread to Roraima, where it was reported in 2008, and to Colombia, where it was reported in 2010. Its possible spread to other regions of Brazil is a threat to Brazilian citriculture. This study reports the current distribution of S. hindustanicus and potential predators of this pest and other mites associated with citrus in Roraima. A survey was conducted in August and September 2015 in the 15 municipalities of the state. In each municipality, orchards and citrus plants in backyards and public areas along highways and in urban areas were sampled. Samples of leaves and fruits were collected to identify the mite and its natural enemies. Schizotetranychus hindustanicus was found in all 15 municipalities in the state of Roraima. In total, 308 associated mites were found, with S. hindustanicus being the most abundant phytophagous mite, followed by Brevipalpus yothersi Baker. Amblyseius aerialis (Muma) was the most abundant predator, followed by Iphiseiodes zuluagai Denmark and Muma and Euseius concordis (Chant). The broad dispersal of S. hindustanicus in Roraima increases the risks of this pest reaching the main citrus-producing regions in Brazil.


Asunto(s)
Distribución Animal , Tetranychidae , Animales , Brasil
10.
Oper Dent ; 44(4): 396-404, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30517069

RESUMEN

OBJECTIVE: To evaluate the effect of different photoinitiator systems on photopolymerizing resin cements through ceramic veneers with different thickness on microshear bond strength (µSBS), flexural strength (FS), and ultimate tensile strength (UTS) and verify the light attenuation through these ceramic veneers. METHODS AND MATERIALS: Four photopolymerizing experimental resin cements were produced with the same resin matrix and associated with four different photoinitiator systems: camphorquinone (CQ), diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), Ivocerin, and TPO + Ivocerin. Eighty disc-shaped ceramic veneers (IPS Empress Esthetic, Ivoclar Vivadent) were fabricated (10-mm diameter) in two different thicknesses: 0.7 and 1.5 mm. A previously characterized multiwave LED (Bluephase G2, Ivoclar Vivadent) was standardized for 40 seconds of photoactivation. Light transmittance through each ceramic veneer thickness (n=5) was measured using a spectrometer (USB 2000, Ocean Optics). The µSBS of each resin cement (n=15) to the ceramic veneer was evaluated using 0.5-mm cylinders with 0.7-mm diameters photoactivated through the different ceramic veneer thicknesses. Samples for FS and UTS tests were made either with or without ceramics veneers (0.7 and 1.5 mm) fixed to the light-curing tip. Data were submitted to two-way analysis of variance and the Tukey test (α=0.05). RESULTS: The multiwave LED emitted higher irradiance into the blue wavelength spectra than into the violet wavelength spectra (p=0.0001). Light transmittance through the ceramic veneers was reduced in a systematic manner based on thickness regardless of the wavelength spectra emitted from the multiwave LED (p=0.00037). The µSBS was reduced in a systematic manner based on thickness regardless of the photoinitiator system (p<0.05). However, resin cements with CQ and Ivocerin showed higher bond strength values in comparison to the resin cement with TPO regardless of the ceramic veneer thickness (p<0.05). The FS and UTS means decreased (p<0.05) with the interposition of 0.7- and 1.5-mm ceramic veneers for all resin cements. The resin cement containing only TPO showed the lowest FS and UTS means (p<0.05) for all ceramic veneers. CONCLUSIONS: The thickness of the ceramic veneers reduced the irradiance of the multiwave LED in all wavelength spectra. Ivocerin alone or associated with TPO showed to be an effective alternative photoinitiator to substitute for CQ. The resin cement containing only TPO had lower bond strength values in comparison to resin cements with CQ, Ivocerin, and Ivocerin + TPO.


Asunto(s)
Coronas con Frente Estético , Cementos de Resina , Cerámica , Color , Porcelana Dental , Ensayo de Materiales
11.
J Insect Physiol ; 84: 103-113, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26620152

RESUMEN

Biologists who study insect-induced plant galls are faced with the overwhelming diversity of plant forms and insect species. A challenge is to find common themes amidst this diversity. We discuss common themes that have emerged from our cytological and histochemical studies of diverse neotropical insect-induced galls. Gall initiation begins with recognition of reactive plant tissues by gall inducers, with subsequent feeding and/or oviposition triggering a cascade of events. Besides, to induce the gall structure insects have to synchronize their life cycle with plant host phenology. We predict that reactive oxygen species (ROS) play a role in gall induction, development and histochemical gradient formation. Controlled levels of ROS mediate the accumulation of (poly)phenols, and phytohormones (such as auxin) at gall sites, which contributes to the new cell developmental pathways and biochemical alterations that lead to gall formation. The classical idea of an insect-induced gall is a chamber lined with a nutritive tissue that is occupied by an insect that directly harvests nutrients from nutritive cells via its mouthparts, which function mechanically and/or as a delivery system for salivary secretions. By studying diverse gall-inducing insects we have discovered that insects with needle-like sucking mouthparts may also induce a nutritive tissue, whose nutrients are indirectly harvested as the gall-inducing insects feeds on adjacent vascular tissues. Activity of carbohydrate-related enzymes across diverse galls corroborates this hypothesis. Our research points to the importance of cytological and histochemical studies for elucidating mechanisms of induced susceptibility and induced resistance.


Asunto(s)
Insectos/fisiología , Células Vegetales/parasitología , Tumores de Planta/parasitología , Plantas/parasitología , Adaptación Fisiológica , Animales , Interacciones Huésped-Parásitos , Reguladores del Crecimiento de las Plantas/fisiología
12.
Neotrop Entomol ; 42(3): 230-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23949804

RESUMEN

The analysis on nine inventories on the richness and diversity of galling herbivores in Brazil accounted for 806 gall systems occurring in 443 host-plant species from 74 plant families. This checklist of the Brazilian gall morphotypes proposes seven standardized morphotypes and five additional shapes that group the majority of the three-dimensional shapes reported in literature. Criteria are proposed to standardize the terminology, and a critical analysis is provided aiming to avoid possible inconsistencies in order to generate easily comparable data in future inventories. The morphotypes are herein catalogued in alphabetical order, accompanied by a conceptual definition, an illustration, and examples that best represent the shape. It is proposed that the inventories should present at least the (1) host-plant species, (2) galling herbivore species or its identification to the lowest possible taxonomic level, (3) host-plant galled organ and gall position, (4) gall morphotype, (5) gall color and registration of indumentum when present, (6) gall phenological and developmental data, (7) association with other trophic levels, and (8) additional information, such as dimension, and number of chamber(s).


Asunto(s)
Lista de Verificación , Tumores de Planta , Plantas/anatomía & histología , Brasil
13.
Arq. bras. med. vet. zootec ; 65(4): 1084-1090, Aug. 2013. ilus, tab
Artículo en Inglés | LILACS | ID: lil-684464

RESUMEN

The aim of this study is to evaluate the possible alterations in radiodensity of the hepatic parenchyma and spleen resulting from the corticotherapy with prednisone, correlating these findings with serum biochemical hepatic transaminase activity. A clinical trial was performed on eight healthy dogs with the intent of evaluating possible hepatic alterations after prednisone therapy using quantitative computed tomography. All animals received prednisone orally at a dose of 2mg/kg of weight for 30 days. The radiodensity of the liver and spleen was determined before and after the period that the medication was administered. An increase in the radiodensity of the hepatic parenchyma between the initial and final experimental stages was observed. In the present study the existence of early hepatic alterations were verified, which are compatible with glycogen storage.


O objetivo deste estudo é avaliar as possíveis alterações na radiodensidade do parênquima hepático e esplênico decorrentes da corticoterapia com prednisona, correlacionando estes achados com níveis séricos de transaminase bioquímicas hepáticas. Um ensaio clínico foi realizado em oito cães sadios com o objetivo de avaliar possíveis alterações hepáticas após a terapia com prednisona por meio de tomografia computadorizada quantitativa. Todos os animais receberam prednisona por via oral na dose de 2mg / kg de peso por 30 dias. A radiodensidade do fígado e do baço foi determinada antes e após o período em que a medicação foi administrada. Foi observado aumento da radiodensidade do parênquima hepático entre os estágios iniciais e finais do experimento. No presente estudo, foi verificada a existência de alterações hepáticas precoces, que são compatíveis com o acúmulo de glicogênio.


Asunto(s)
Animales , Perros , Evaluación de Síntomas/métodos , Edema/patología , Perros/clasificación
14.
Arq. bras. med. vet. zootec ; 65(4): 1253-1256, Aug. 2013. ilus, tab
Artículo en Inglés | LILACS | ID: lil-684487

RESUMEN

Este estudo caracteriza a radiodensidade do córtex renal de 10 cães e 10 gatos adultos, clinicamente saudáveis, por meio de exames de tomografia computadorizada helicoidal. Em cada rim, a radiodensidade renal foi estimada pelo valor médio das três regiões de interesse na região cortical, selecionados no polo cranial, polo caudal e hilo renal. A radiodensidade média do córtex renal nos cães e nos gatos foi, respectivamente, 28,4±4,7 e 22,4±3,6 unidades Hounsfield (HU). Verificou-se que os gatos possuem córtex renal hipoatenuante quando comparado com cães, um fato que está associado à maior deposição de conteúdo lipídico nos rins felinos. A diferença na radiodensidade encontrada entre o córtex renal de cães e de gatos é importante para uma correta interpretação dos achados renais no exame tomográfico.


Asunto(s)
Animales , Perros/fisiología , Corteza Renal/anatomía & histología , Gatos/fisiología , Riñón/anatomía & histología , Tomografía/métodos
15.
Zootaxa ; 3734: 317-30, 2013 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-25277915

RESUMEN

A new gall-inducing genus and species of felt scales (Hemiptera: Coccoidea: Eriococcidae) found on the leaves and twigs of Matayba guianensis (Sapindaceae) in Brazil is described: Bystracoccus Hodgson gen n. and B. mataybae Hodgson, Isaias & Oliveira sp. n.  This is the first record of an eriococcid inducing leaf and stem galls on Sapindaceae and is only the second example of a member of the Eriococcidae to induce stem galls in which the insects diapause during the dry (winter) season.  Only the adult female, second-instar female and crawler are known.  The species overwinters as the first-instar nymph in pit galls on the twigs but spends the rest of the year associated with two-chambered galls on the leaves.  It has recently become clear that South America has a rich felt-scale insect fauna many of which induce galls. It has proved very difficult to place this new genus in a family as it appears to fall between the Eriococcidae and Beesoniidae but is here placed in the eriococcids based on the similarity of the first-instar nymphs and the abundance of this family in the Neotropics.  However, the dorsum of the abdomen of the mature adult female becomes heavily sclerotised, forming a round plug-like structure that completely fills the gall orifice.  This structure shows remarkable morphological similarities to that of the beesoniid Danumococcus parashoreae Takagi & Hodgson found on Parashorea tomentella (Dipterocarpaceae) in Sabah, Malaysia, with which it is compared along with other eriococcid genera known from South America.


Asunto(s)
Hemípteros/clasificación , Enfermedades de las Plantas/parasitología , Tumores de Planta/parasitología , Sapindaceae/parasitología , Estructuras Animales/anatomía & histología , Animales , Brasil , Ecosistema , Femenino , Hemípteros/anatomía & histología , Hemípteros/crecimiento & desarrollo , Masculino , Ninfa/anatomía & histología , Ninfa/clasificación , Ninfa/crecimiento & desarrollo , Hojas de la Planta/parasitología
16.
J Biosci ; 37(6): 1079-88, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23151797

RESUMEN

We correlated root growth inhibition with aluminium (Al(3+)) localization and toxicity symptoms in rice roots using seedlings of two genotypes (tolerant and sensitive) that were exposed to different AlCl(3) concentrations. Al(3+) localization was evaluated by hematoxylin in primary roots and by morin in cross-sections of the root tips. Neutral invertase enzyme activity and callose (1 -- 3, beta-D-glucan) accumulation were observed and compared with Al(3+) accumulation sites. Root growth was inhibited by Al(3+) in a concentration-specific manner and proportional to the increase of hematoxylin staining, being more pronounced in the sensitive genotype. Morin staining showed the presence of Al(3+) deep within the roots of the sensitive genotype, indicating that the metal was able to penetrate beyond the first few cell layers. In the tolerant genotype, Al(3+) penetration was restricted to the first two cell layers. Ruptures in exodermis and epidermis layers by lateral root protrusions in both genotypes allowed Al3+ to enter into the roots. More intense activity of invertase in roots of the tolerant genotype was also observed, which could be related to greater root growth of this cultivar when submitted to Al(3+) stress. Moreover, Al(3+)-induced callose accumulation was a late response occurring in the same areas where Al(3+) was present.


Asunto(s)
Aluminio/metabolismo , Aluminio/toxicidad , Oryza/efectos de los fármacos , Raíces de Plantas/efectos de los fármacos , Oryza/enzimología , Oryza/crecimiento & desarrollo , Raíces de Plantas/enzimología , Raíces de Plantas/crecimiento & desarrollo , beta-Fructofuranosidasa/metabolismo
17.
Arq. bras. med. vet. zootec ; 64(3): 593-598, June 2012. ilus, tab
Artículo en Portugués | LILACS | ID: lil-640122

RESUMEN

Estabeleceram-se valores de média radiodensidade do osso trabecular das vértebras lombares de 16 gatos adultos, hígidos, por meio da tomografia computadorizada quantitativa (TCQ). O valor médio de radiodensidade do osso trabecular da segunda vértebra lombar foi de 436,1±42,1 unidades Hounsfield, com distribuição não homogênea da radiodensidade no corpo vertebral.


The radiodensity of the trabecular bone of the lumbar vertebrae in 16 healthy adult cats was studied using quantitative computed tomography (QCT). The average radiodensity of the trabecular bone of the second lumbar vertebra was 436.1±42.1 Hounsfield units. However, there was a nonhomogeneous radiodensity distribution of the vertebral body.

18.
Arq. bras. med. vet. zootec ; 64(3): 766-768, June 2012.
Artículo en Portugués | LILACS | ID: lil-640145

RESUMEN

Quantitative computed tomography was used to determine the radiodensity of bony plates. The CT scans provided information regarding radiodensity of bony plates and allowed to verify the uniformity of bone mineral density in their scope. The proposed methodology should be considered as another tool for determining the resistance of these biomaterials.

19.
Neotrop Entomol ; 41(4): 315-23, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23950068

RESUMEN

The coconut mite, Aceria guerreronis Keifer, is one of the main pests of coconut palms (Cocos nucifera) in northeastern Brazil. The objective of this study was to evaluate the levels of the coconut mite and other mites on coconut palms in the state of São Paulo and to estimate the possible role of predatory mites in the control of this pest. The effect of cultivated genotypes and sampling dates on the mite populations was also estimated. We sampled attached fruits, leaflets, inflorescences, and fallen fruits. The coconut mite was the main phytophagous mite found on attached and fallen fruits, with average densities of 110.0 and 20.5 mites per fruit, respectively. The prevalent predatory mites on attached and fallen fruits were Proctolaelaps bulbosus Moraes, Reis & Gondim Jr. and Proctolaelaps bickleyi (Bram), both Melicharidae. On leaflets, the tenuipalpids Brevipalpus phoenicis (Geijsks) and Tenuipalpus coyacus De Leon and the tetranychid Oligonychus modestus (Banks) were the predominant phytophagous mites. On both leaflets and inflorescences, the predominant predatory mites belonged to the Phytoseiidae. Neoseiulus baraki (Athias-Henriot) and Neoseiulus paspalivorus (De Leon), predators widely associated with the coconut mite in northeastern Brazil and several other countries, were not found. The low densities of the coconut mite in São Paulo could be related to prevailing climatic conditions, scarcity of coconut plantations (hampering the dispersion of the coconut mite between fields), and to the fact that some of the genotypes cultivated in the region are unfavorable for its development.


Asunto(s)
Cocos/parasitología , Ácaros/fisiología , Animales , Brasil
20.
Arq. bras. med. vet. zootec ; 63(6): 1547-1552, dez. 2011. tab
Artículo en Portugués | LILACS, VETINDEX | ID: lil-608981

RESUMEN

Realizou-se a detecção do gene de Staphylococcus aureus, de enterotoxinas e de resistência à meticilina com extração de DNA feita diretamente de amostras de leite. Das 200 amostras estudadas, 145 (72,5%) amplificaram o gene femA, e estas foram analisadas quanto à presença dos genes sea, seb, sec e mecA. Os genes das enterotoxinas mais prevalentes foram: sea (60%), seb (37,9%) e sec (6,9%). Foram encontradas 18 amostras de leite (11,0 %) com S. aureus portadores do gene mecA. A detecção de S. aureus diretamente do leite, sem a necessidade de isolamento bacteriano e a caracterização do potencial enterotoxigênico, demonstra que a técnica de PCR é muito útil para estudos epidemiológicos das infecções estafilocócicas da glândula mamária. O alto percentual (72,5%) de amostras de leite positivas para a presença do gene femA sugere que S. aureus constitui um dos principais agentes causadores de infecções intramamárias na microrregião de Sete Lagoas-MG e que seu potencial enterotoxigênico e presença do gene mecA, que identifica o S. aureus resistente à meticlina, representa um risco potencial à saúde pública.


This work was performed to detect the Staphylococcus aureus gene, enterotoxins resistance to methicillin with the extraction of DNA directly from milk samples. Of the 200 samples studied 145 (72.5%) amplified the femA gene, which were analyzed regarding the presence of sea, seb, sec and mecA genes. The most prevalent enterotoxins genes were: sea (60%), seb (37.9%) and sec (6.9%). 18 milk samples (11 %) had S. aureus carrying the mecA gene. The detection of S. aureus directly from the milk, with no need for bacterial isolation and the characterization of the enterotoxigenic potential demonstrate that the PCR technique is very useful for epidemiological studies of staphylococcal infections of the mammary gland. The high percentage (72.5%) of positive milk samples for the presence of the femA gene suggests that S. aureus constitutes of the main agents which cause intramammary infections in the micro region of Sete Lagoas-MG and that its enterotoxigenic potential and the presence of the mecA gene, which identifies the S. aureus resistant to methicillin, represent a potential risk to public health.


Asunto(s)
Resistencia a la Meticilina , Leche/microbiología , Enterotoxinas , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Reacción en Cadena de la Polimerasa
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