Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 29
Filter
1.
Braz. j. biol ; 78(3): 429-435, Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-951570

ABSTRACT

Abstract This study reports the first assessment of endophytic fungi isolated from strawberry leaves and selection of isolates for the control of Duponchelia fovealis, a new pest of strawberries. A total of 400 strawberry leaves of the cultivar 'Albion' were collected in four commercial farms. Leaves were disinfected, cut in fragments, and placed on Petri dishes containing potato dextrose agar media with tetracycline and incubated for 30 days. Following this time, 517 fungal colonies were isolated, and thirteen genera were identified: Cladosporium, Aspergillus, Nigrospora, Fusarium, Trichoderma, Chaetomium, Alternaria, Paecilomyces, Penicillium, Ulocladium, Bipolaris, Diaporthe, and Phoma. Eight isolates belonging to the genera Aspergillus, Diaporthe, Paecilomyces, and Cladosporium were selected for pathogenicity bioassays against third instar larvae of D. fovealis. Isolates of Paecilomyces induced the highest mortality rates.


Resumo Este trabalho apresenta a primeira contribuição no isolamento de fungos endofíticos de folhas de morangueiro e na seleção de isolados para controle de Duponchelia fovealis, uma nova praga do morangueiro. Foram coletadas 400 folhas da cultivar 'Albion' em quatro lavouras comerciais de morangueiro. As folhas foram desinfetadas, cortadas em fragmentos e depositadas em placas de Petri contendo Ágar Batata Dextrose como meio, em conjunto com tetraciclina e incubados durante 30 dias. Um total de 517 colônias fúngicas e treze gêneros foram isolados: Cladosporium, Aspergillus, Nigrospora, Fusarium, Trichoderma, Chaetomium, Alternaria, Paecilomyces, Penicillium, Ulocladium, Bipolaris, Diaporthe e Phoma. Oito isolados pertencentes aos gêneros Aspergillus, Diaporthe, Paecilomyces e Cladosporium foram selecionados para os bioensaios de virulência contra larvas de 3º instar de D. fovealis. Isolados de Paecilomyces causaram as maiores taxas de mortalidade.


Subject(s)
Animals , Plant Diseases/prevention & control , Paecilomyces/pathogenicity , Pest Control, Biological/methods , Lepidoptera/microbiology , Plant Diseases/parasitology , Paecilomyces/isolation & purification , Paecilomyces/physiology , Plant Leaves/parasitology , Fragaria/parasitology , Larva/growth & development , Larva/microbiology , Lepidoptera/growth & development
2.
Braz. j. biol ; 78(4): 636-643, Nov. 2018. tab, graf
Article in English | LILACS | ID: biblio-951591

ABSTRACT

Abstract In this study, we report the first records and morphological characterization of galls in a Cerrado area in western Bahia, Brazil. The data were collected monthly over two hours between March and September 2015. Fifteen gall morphotypes were found in twelve plant species distributed among seven families. The plant family with the greatest richness of galls was Fabaceae (n = 8). The following gall morphologies were found: globoid, lenticular, marginal leaf roll, conical, cylindrical, fusiform, spherical and pocket shaped. Cecidomyiidae induced globoid, lenticular, conical, fusiform, spherical and cylindrical morphotypes. In addition, species of microhymenoptera belonging to the Eulophidae, Eurytomidae and Encyrtidae families were found. Marginal leaf roll and pocket-shaped galls induced by Thysanoptera were also verified. Springtails were also identified as a successor. Undescribed species of Schizomyia and Lopesia were recorded in B. cupulata and Andira humilis, respectively.


Resumo Nesse trabalho são apresentadas informações sobre a ocorrência e a caracterização morfológica de galhas induzidas por insetos em uma área de Cerrado do Oeste da Bahia, Brasil. Os materiais foram coletados mensalmente durante duas horas entre Março e Setembro de 2015. Foram encontrados quinze morfotipos de galhas em doze espécies vegetais, distribuídas em sete famílias. A família de planta com maior riqueza de galhas foi Fabaceae (n = 8). Com relação à morfologia externa, foram encontradas galhas com forma globoide, lenticular, enrolamento marginal, cônica, cilíndrica, fusiforme, esférica e bolso. Quanto à fauna associada às galhas, os morfotipos globoide, cônico, lenticular, fusiforme, esférico e cilíndrico foram induzidos por Cecidomyiidae. Além disso, espécies de microhimenópteros pertencentes às famílias Eulophidae, Eurytomidae e Encyrtidae foram encontrados. A indução de galhas por Thysanoptera, nos morfotipos enrolamento marginal e formato de bolso, também foi detectada. Espécies de colembôlos foram identificadas como sucessoras. Espécies não descritas de Schizomyia e Lopesia foram registradas em Bauhinia cupulata e Andira humilis, respectivamente.


Subject(s)
Animals , Plant Tumors/parasitology , Plant Leaves/parasitology , Host-Parasite Interactions/physiology , Insecta/physiology , Oviposition/physiology , Brazil , Insecta/classification
3.
Braz. j. biol ; 76(3): 787-795, tab, graf
Article in English | LILACS | ID: lil-785051

ABSTRACT

Abstract Thirty-one morphotypes of insect galls and two flower damages were found on 16 families, 22 genera and 24 plant species in Restinga de Marambaia (Barra de Guaratiba, Rio de Janeiro, RJ). Fabaceae and Myrtaceae were the plant families with the greatest richness of insect galls (4 and 6 morphotypes, respectively), and the greatest number of galled plants (four and three species, respectively). Galls were mostly found on leaves and stems (77% and 10%, respectively). The galling insects are represented by Diptera, Lepidoptera, and Hemiptera. The majority of the galls (81%) were induced by gall midges (Cecidomyiidae: Diptera).


Resumo Foram encontrados 31 morfotipos de galhas de insetos e dois danos em flores em 16 famílias, 22 gêneros e 24 espécies de plantas, na Restinga de Marambaia (Barra de Guaratiba, Rio de Janeiro, RJ). Fabaceae e Myrtaceae foram as famílias de plantas com maior riqueza de galhas (4 e 6 morfotipos, respectivamente) e maior número de espécies com galhas (quatro e três espécies, respectivamente). As galhas predominaram nas folhas e caules (77% e 10%, respectivamente). Os insetos galhadores estão representados por Diptera, Lepidoptera e Hemiptera. A maioria das galhas (81%) foi induzida por Cecidomyiidae (Diptera).


Subject(s)
Animals , Plant Tumors/parasitology , Plants/parasitology , Host-Parasite Interactions/physiology , Insecta/physiology , Plant Tumors/classification , Brazil , Plant Stems/parasitology , Plant Leaves/parasitology , Myrtaceae/parasitology , Diptera/classification , Diptera/physiology , Hemiptera/classification , Hemiptera/physiology , Insecta/classification , Fabaceae/parasitology , Lepidoptera/classification , Lepidoptera/physiology
4.
Rev. biol. trop ; 64(3): 1209-1222, jul.-sep. 2016. tab, ilus
Article in English | LILACS | ID: biblio-958207

ABSTRACT

AbstractTreehoppers are known for their substrate-borne communication and some of them also for their subsocial behavior. Following a more general study of the natural history and substrate-borne signal repertoire of the treehopper Ennya chrysura, the objective of this paper was to explore in greater depth the signals and other behaviors associated specifically to egg-guarding. Theese were studied both in natural and laboratory conditions between July, 2000 and March, 2004. The spatial distribution of egg guarding females was studied in the natural population; recording equipment and playback experiments were used in the laboratory and then analyzed digitally. Under natural conditions (San Antonio de Escazú, Costa Rica), female E. chrysura guard their egg masses and egg-guarding was associated with lower parasitism of the eggs from the wasps Gonatocerus anomocerus and Schizophragma sp. (Mymaridae). Females tended to place their eggs close to other egg-guarding females and they produced substrate-borne vibrations when disturbed. An aggregated pattern under natural conditions was confirmed by calculating dispersion indices from egg-clutch data obtained from 66 leaves in the field. The disturbance signal was characterized from laboratory recordings of substrate-borne vibrations of 10 egg-guarding females. Experiments conducted in the laboratory with 18 egg-guarding females showed that those which were previously exposed to the disturbance signal of another female moved slightly or vibrated more during playbacks and that they reacted more quickly and exhibited more deffensive behaviors in response to a tactile stimulus. The signals produced while defending against egg parasites may therefore function as an alarm and favor aggregating behavior of egg-guarding females. Rev. Biol. Trop. 64 (3): 1209-1222. Epub 2016 September 01.


ResumenDespués de un estudio más general sobre la historia natural y la comunicación por vibraciones de sustrato del membrácido Ennya chrysura, este artículo explora con mayor profundidad los comportamientos específicamente relacionados con el cuido de los huevos. En condiciones naturales (San Antonio de Escazú, Costa Rica), las hembras de E. chrysura con frecuencia protegen sus masas de huevos, y el cuido está asociado con un menor porcentaje de parasitismo causado por las avispas parasitoides de huevos Gonatocerus anomocerus and Schizophragma sp. (Mymaridae). Las hembras tendían a poner sus huevos en la cercanía de otras hembras con huevos, y producían vibraciones de sustrato en respuesta a disturbios. Se confirmó un patrón agregado bajo condiciones naturales, calculando índices de dispersión a partir del número de masas de huevos en 66 hojas. La señal fue descrita a partir de grabaciones hechas en el laboratorio con 10 hembras que protegían sus huevos. Los experimentos conducidos con 18 hembras mostraron que aquellas que fueron expuestas a la señal de disturbio de otra hembra, se movieron ligaramente o vibraron más durante el experimento, y reaccionaron a un estímulo táctil más rápidamente y con un mayor número de comportamientos defensivos. Las señales producidas durante la defensa de huevos podrían entonces funcionar como alarma, y favorecer la agrupación con otras hembras que también protegen sus huevos.


Subject(s)
Animals , Male , Female , Ovum/parasitology , Behavior, Animal/physiology , Hemiptera/physiology , Appetitive Behavior , Reference Values , Social Behavior , Time Factors , Vibration , Sex Factors , Statistics, Nonparametric , Plant Leaves/parasitology , Clutch Size , Animal Distribution/physiology
5.
Indian J Exp Biol ; 2014 Dec; 52(12): 1201-1205
Article in English | IMSEAR | ID: sea-153812

ABSTRACT

Wild crucifers namely Arabidopsis thaliana, Brassica fruticulosa, B. rugosa, B. spinescens, B. tournefortii, Camelina sativa, Capsella bursa-pastoris, Crambe abysinnica, Cronopus didymus, Diplotaxis assurgens, D. gomez-campoi, D. muralis, D. siettiana, D. tenuisiliqua, Enatharocarpus lyratus, Lepidium sativum and Sinapis alba along with five cultivated Brassica species including B. rapa (BSH-1), B. juncea (Rohini), B. napus (GSC-6), B. carinata (DLSC-2) and Eruca sativa (T-27) were screened against mustard aphid Lipaphis erysimi (Kalt.) with a standardized technique under definite level of aphid pressure developed using specially designed cages. Observations have revealed that B. fruticulosa, B. spinescens, Camelina sativa, Crambe abysinnica and Lepidium sativum were resistant to mustard aphid L. erysimi with aphid infestation index (AII) ≤1. Capsella bursa-pastoris was highly susceptible to bean aphid, Aphis fabae during its vegetative stage (with 100% mortality). Other genotypes were found in the range of ‘susceptible’ to ‘highly susceptible’ with AII ranging 3-5.


Subject(s)
Animals , Aphids/physiology , Brassicaceae/classification , Brassicaceae/growth & development , Brassicaceae/parasitology , Disease Resistance , Host-Parasite Interactions , Plant Diseases/parasitology , Plant Leaves/growth & development , Plant Leaves/parasitology , Species Specificity
6.
Rev. biol. trop ; 62(2): 819-827, Jun.-Aug. 2014. ilus, graf, tab
Article in Spanish | LILACS | ID: lil-715474

ABSTRACT

Rice cultivars are affected directly and indirectly by the insect sogata. The mechanical damage or direct loss, is produced after feeding and ovoposition on the young leaves tissues, while the indirect damage is produced after the transmission of the Rice hoja blanca virus. We studied the morpho-anatomic structures associated with the resistance of the mechanical damage produced by the insect, in six rice cultivars, including controls for resistance and susceptibility (Makalioka and Bluebonnet 50), during August 2011, in Fundacion Danac, Venezuela. Samples were taken from leaf 3, where cuticle thickness, presence of macrohair, microhair and silica bodies in the second third of the leaf was evaluated. A significant difference to thickness of the cuticle, the presence of microhair in the leaves, and presence of silica bodies was observed among cultivars, determining a significant correlation among the number of macrohair and microhair in the adaxial leaf blade with the presence of silica bodies, and thickness of the cuticle and number of posed insects. Thickness of the cuticle and presence of silica bodies in the intercostals space of microhair and macrohair showed to be the variables most related to mechanical damage and resistance mechanism.


El arroz es afectado directa e indirectamente por el insecto sogata. El daño directo o mecánico es debido a la postura de huevos y alimentación del tejido foliar por parte del insecto y el daño indirecto que ocurre es por la trasmisión del virus de la hoja blanca del arroz. El ensayo fue conducido en la Fundación DANAC en agosto 2011, con la finalidad de evaluar las estructuras morfoanatómicas asociadas con la resistencia al daño mecánico en seis cultivares de arroz que incluyen a los testigos de resistencia y susceptibilidad (Bluebonnet 50 y Makalioka). En el tercio medio de la tercera hoja, se evaluaron las variables grosor de la cutícula, presencia de macropelos, micropelos y cuerpos silíceos. Se observaron diferencias significativas entre los cultivares para el grosor de cutícula, número de micropelos y presencia de cuerpos silíceos, se determinó una correlación significativa entre el número de macro-pelos y micropelos en la cara adaxial con la presencia de cuerpos silíceos y el grosor de la cutícula y el número de insectos posados a las 96h. El grosor de la cutícula y la presencia de cuerpos silíceos en los espacios intercostales de los micropelos y macropelos mostraron ser los caracteres más relacionados con la resistencia al daño mecánico y los mecanismos de resistencia al insecto.


Subject(s)
Animals , Hemiptera/physiology , Oryza/parasitology , Plant Epidermis/parasitology , Plant Leaves/parasitology , Host-Parasite Interactions , Hemiptera/classification , Oryza/cytology , Plant Epidermis/cytology , Plant Leaves/cytology , Venezuela
7.
Bol. latinoam. Caribe plantas med. aromát ; 12(2): 162-175, mar. 2013. ilus, tab
Article in Spanish | LILACS | ID: lil-722789

ABSTRACT

Total phenols, total tannins, proanthocyanidins, total flavonoids and total hydroxycinnamic acids of healthy leaves and galls of Schinus longifolius (Lindl.) Speg. (Anacardiaceae) infected by Calophya mammifex (Hemiptera - Calophyidae) were analized. The gall presents a qualitative and quantitative change in the polyphenols analysed, with a reduction of phenols, tannins, flavonoids and hydroxycinnamic acids and an increased content of proanthocyanidins, whose monomer yielded cyanidin after acid cleavage. An anatomical survey was performed and clusters of sclereids and an increased vascular development respect of the healthy leaf were found. An histochemical survey showed a differential expression of polyphenolic compounds in their tissues. C. mammifex could use the gall as a shelter against adverse weather conditions and predators, and also provide food with less potentially harmful compounds in the early stages of its development.


Se analizaron los fenoles totales, taninos totales, proantocianidinas, flavonoides totales y ácidos hidroxicinámicos totales de hojas sanas y agallas de Schinus longifolius (Lindl.) Speg. (Anacardiaceae) infectado por Calophya mammifex (Hemiptera - Calophyidae). La agalla presenta una variación cuali-cuantitativa de los polifenoles estudiados, con una disminución de los fenoles, taninos, flavonoides y ácidos hidroxicinámicos y un aumento en el contenido de proantocianidinas, cuyo monómero se transforma en cianidina luego del clivaje ácido. Se realizó además un análisis anatómico de la agalla donde se encontraron acúmulos de esclereidas y un mayor desarrollo vascular respecto de la hoja sana y un ensayo histoquímico que mostró una expresión diferencial de metabolitos polifenólicos en sus tejidos. C. mammifex utiliza la agalla como refugio contra las condiciones climáticas adversas y predadores y provee además de alimento con menos compuestos potencialmente perjudiciales en las etapas tempranas de su desarrollo.


Subject(s)
Anacardiaceae/parasitology , Anacardiaceae/chemistry , Hemiptera/physiology , Plant Leaves/chemistry , Polyphenols/analysis , Phenols/analysis , Histocytochemistry , Plant Leaves/parasitology , Proanthocyanidins , Polyphenols/metabolism , Tannins/analysis
8.
Braz. j. biol ; 73(1): 179-184, Feb. 2013. ilus
Article in English | LILACS | ID: lil-671377

ABSTRACT

The larvae of the southern beet webworm Herpetogramma bipunctalis (Fabricius, 1794) damage the leaves of species in the plant genus Rubus. The present study investigated the biology of H. bipunctalis and developed a protocol for raising H. bipunctalis under laboratory conditions. On the basis of the biological data, we devised a life table. In order to develop the rearing procedures, we determined which oviposition substrate and blackberry cultivar were the most appropriate for larval development. The mean durations of the egg, larval, and pupal stages were 5.59 days, 26.37 days, and 13.37 days, respectively, and the corresponding survival rates were 80.83%, 49.07%, and 83.23%. The mean pupal weight was 0.0491 g for males and 0.0536 g for females. The mean life cycle (egg-to-adult) period was 45.33 days, and overall survival to adulthood was 33.01%. H. bipunctalis females laid a mean of 252.63 eggs over a mean of 13.60 days of oviposition; the mean pre-oviposition period was 2.67 days. Mean female and male life spans were 17.51 and 19.25 days, respectively, and the sex ratio was 0.51. The life-table data indicated that H. bipunctalis can reproduce 57.9 times per generation. Each cage contained one blackberry leaf placed on a paper towel. This method allowed us to obtain the greatest number of eggs. The larval stage was shorter for insects reared on leaves of the Guarani cultivar than for those reared on leaves of the Xavante cultivar (22.63 vs. 26.37 days). These basic data can aid in establishing strategies for the management of H. bipunctalis on blackberry farms.


Lagartas de Herpetogramma bipunctalis (Fabricius, 1794) causam danos nas folhas da amoreira-preta (Rubus spp.). O objetivo deste trabalho foi estudar sua biologia e desenvolver uma técnica de criação, em condições de laboratório. Com os dados de biologia, foi elaborada uma tabela de vida de fertilidade. Para o estudo da técnica de criação, foram determinados o substrato para obtenção de ovos e a cultivar de amoreira-preta mais adequada para o desenvolvimento larval. A duração dos estágios de ovo, lagarta e pupa foram de 5,59, 26,37 e 13,37 dias, com sobrevivência de 80,83, 49,07 e 83,23%, respectivamente. O peso das pupas foi 0,0491 g para machos e 0,0536 g para fêmeas. O ciclo biológico (ovo-adulto) foi de 45,33 dias, com sobrevivência total de 33,01%. As fêmeas colocaram, em média, 252,63 ovos durante 13,60 dias, com um período de pré-oviposição de 2,67 dias. A longevidade média de fêmeas e machos foi de 17,51 e 19,25 dias, respectivamente, e a razão sexual, de 0,51. Por meio da tabela de vida de fertilidade, determinou-se uma capacidade de aumento de 57,9 vezes a cada geração. Gaiolas revestidas com papel toalha e com a presença de folhas de amoreira-preta propiciaram a obtenção de uma maior quantidade de ovos. A duração do estágio larval para os insetos alimentados com folhas de amoreira-preta cv. Guarani (22,63 dias) foi menor do que aqueles alimentados com folhas da cv. Xavante (26,37 dias). Estas informações são básicas e auxiliarão em futuros estudos, visando ao estabelecimento de estratégias de manejo de H. bipunctalis em amoreira-preta.


Subject(s)
Animals , Female , Male , Lepidoptera/growth & development , Plant Leaves/parasitology , Rosaceae/parasitology , Lepidoptera/physiology , Life Cycle Stages/physiology , Oviposition/physiology , Reproduction/physiology , Sex Ratio
9.
Braz. j. biol ; 72(4): 915-918, Nov. 2012. tab
Article in English | LILACS | ID: lil-660389

ABSTRACT

The purpose of this study was to elaborate a preliminary list of the mite species associated with rubber trees in the municipality of Santana, in the state of Amapá, Brazil. Two collections of rubber tree leaves were conducted on May 2nd and June 5th , 2010. Twenty-five plants were sampled at random. Three leaves were collected per plant, from the lower third of the crown. The samples were placed in paper bags, packed in an isothermal box chilled gel-based pulp plant (Gelo-X®), and transported to the Entomology Laboratory at Embrapa Amapá, in Macapá. The leaflets were examined under a stereomicroscope, and the mites found on the adaxial and abaxial surfaces of the leaves were collected with a stilet, mounted on microscope slides in Hoyer's medium, and later identified. We collected a total of 1,722 mites of 10 families: Acaridae, Cunaxidae, Eriophyidae, Iolinidae, Phytoseiidae, Stigmaeidae, Tarsonemidae, Tenuipalpidae, Tydeidae, and Winterschmidtiidae, in addition to unidentified species of the suborders Oribatida and Astigmatina. The family Phytoseiidae represented only 2.90% of specimens collected, but showed the highest species richness (5 species). The only representative of Tenuipalpidae was Tenuipalpus heveae Baker, 1945, but 81.13% of the mites collected in this study belonged to this species.


O objetivo deste estudo foi elaborar uma lista preliminar das espécies de ácaros associadas à seringueira, no município de Santana, Estado do Amapá. Foram realizadas duas coletas de folhas de seringueira, nos dias 2 de maio e 5 de junho de 2010. Foram tomadas aleatoriamente 25 plantas, de cada uma das quais foram coletadas três folhas, no terço inferior da copa. As amostras foram acondicionadas em sacos de papel, mantidas em caixa isotérmica refrigerada com gel à base de celulose vegetal (Gelo-X®) e transportadas até o Laboratório de Entomologia da Embrapa Amapá, em Macapá. A triagem dos folíolos foi realizada com o auxílio de estereomicroscópio. Os ácaros encontrados nas faces adaxial e abaxial das folhas foram capturados com um estilete, montados em lâminas de microscopia em meio de Hoyer e, posteriormente, identificados. Foram coletados 1.722 ácaros, pertencentes a dez famílias: Acaridae, Cunaxidae, Eriophyidae, Iolinidae, Phytoseiidae, Stigmaeidae, Tarsonemidae, Tenuipalpidae, Tydeidae e Winterschmidtiidae, além de espécies não identificadas das subordens Oribatida e Astigmatina. A família Phytoseiidae representou apenas 2,90% do total de espécimes coletados, porém apresentou a maior riqueza em espécies (cinco espécies). A família Tenuipalpidae, embora representada apenas por Tenuipalpus heveae Baker, 1945, apresentou o maior número de espécimes capturados (81,13%).


Subject(s)
Animals , Hevea/parasitology , Mites/classification , Brazil , Plant Leaves/parasitology
10.
Rev. bras. plantas med ; 13(2): 215-222, 2011. ilus
Article in English | LILACS | ID: lil-596397

ABSTRACT

Melia azedarach (cinnamon) and Azadirachta indica (neem) have a variety of biologically active ingredients against virus, bacteria and protozoan parasites; however, little is known about their action on Toxoplasma gondii intracellular development. Toxoplasma gondii infects all eukaryotic cells, where it establishes and multiplies inside a modified vacuole called the parasitophorous vacuole until the cell ruptures, re-infecting other cells and establishing the infection. There are no efficient chemotherapies for the elimination of T. gondii, minimizing side effects. In this study, we performed in vitro assays with neem and cinnamon aqueous extracts against the intracellular development of T. gondii tachyzoites. After treatment with neem and cinnamon for 24 h, the percentage of infected cells and the number of intracellular parasites drastically decreased. This effect was concentration-dependent. During the incubation of the extracts, progressive morphological and ultrastructure alterations led to intense vesiculation and complete elimination of the parasite from the intracellular medium. However, during the treatment with extracts, no morphological effects were observed in the structure of the host cell. These results suggest that the aqueous extracts of neem and cinnamon were capable of interfering with and eliminating the intracellular development of Toxoplasma gondii.


Melia azedarach (canela) e Azadirachta indica (nim) apresenta grande variedade de ingredientes biologicamente ativos contra vírus, bactérias e protozoários, mas nenhum efeito sobre o desenvolvimento intracelular do Toxoplasma gondii é conhecido. Toxoplasma gondii infecta todos os tipos de células Eucarióticas, onde se estabelece no meio intracelular em vacúolo modificado conhecido como vacúolo parasitóforo. Neste vacúolo ocorre a replicação levando a ruptura da célula hospedeira e reinfecção de novas células, perpetuando a infecção. A quimioterapia utilizada não é capaz de eliminar o parasita além de induzir fortes efeitos colaterais. Neste estudo, nós demonstramos o efeito in vitro de extratos aquosos da canela e nim sobre o desenvolvimento intracelular do taquizoíto do Toxoplasma gondii. Após tratamento de nim e canela por 24 h, a porcentagem de infecção e o número de taquizoítos intracelulares decaiu drasticamente. Este efeito foi concentração-dependente. Durante incubação dos extratos, uma progressiva desorganização morfológica e ultraestrutural levaram a formação de intensa vesiculação e completa destruição do parasita, que passou a uma estrutura amorfa, antes da completa eliminação do meio intracelular. No entanto durante o tratamento com os extratos, efeitos morfológicos não foram observados nas estruturas da célula hospedeira. Estes resultados sugerem que os extratos aquosos de nim e canela foram capazes de interferir e eliminar o desenvolvimento intracelular do Toxoplasma gondii.


Subject(s)
Azadirachta/analysis , Intracellular Space/parasitology , Plant Extracts/chemistry , Plant Leaves/parasitology , In Vitro Techniques , Toxoplasma/parasitology , Azadirachta/parasitology , Cinnamomum zeylanicum/parasitology , Cytotoxins/physiology , Cytotoxins/chemistry
11.
Neotrop. entomol ; 39(4): 543-548, July-Aug. 2010. graf
Article in Portuguese | LILACS | ID: lil-558839

ABSTRACT

The effects of increasing plant diversity on the population of the coffee leaf-miner Leucoptera coffeella (Guérin-Mèneville) were investigated in two organic coffee production systems. One system consisted of coffee intercropped with banana trees (shaded system) and the other one of coffee intercropped with pigeon pea (unshaded system). The increase in plant diversity on both systems was achieved via introduction of green manures such a perennial pea nut, sunn hemp and Brazilian lucerne. The population of L. coffeella, predation and parasitism of L. coffeella mines were biweekly evaluated during eight months. The increase in plant diversity on both systems did not affect the attack of L. coffeella on coffee leaves and the mine parasitism rate. However, there was a positive and significant relationship between increasing plant diversity and coffee leaf mine predation by wasps on unshaded coffee system and a negative relationship on shaded coffee system.


Subject(s)
Animals , Coffea/parasitology , Lepidoptera/physiology , Plant Leaves/parasitology
12.
Braz. j. biol ; 70(1): 103-109, Feb. 2010. ilus, tab
Article in English | LILACS | ID: lil-539738

ABSTRACT

Folivore cerrado caterpillars are found on their host species in low frequencies, which vary between plants and throughout the year. We analysed the effects of climatic variation and of the characteristics of two host species (Miconia, Melastomataceae) on caterpillar abundance. The work was carried out in a cerrado sensu stricto area in Brasília, Federal District, Brazil, from May 1998 to September 1999. One hundred plants of each species were inspected monthly. All caterpillars found were collected and raised in the laboratory with Miconia leaves as food sources. Climatic data for the study area and plant characteristics such as local density, spatial distribution, foliar phenology, leaf pilosity and nutritional content were used to test the effects on caterpillar abundance. Less than 10 percent of the plants had larvae. Caterpillars were more frequent and abundant in M. pohliana, which was also present at higher densities than M. ferruginata. Low caterpillar frequency in host plants and an abundance peak during the dry season are consistent patterns for different cerrado Lepidoptera larvae. This abundance peak, however, is not coincident with higher leaf production in host species. We suggest that M. pohliana's higher local density and better leaf digestibility can account for the higher abundance of caterpillars in this species.


No cerrado, as lagartas de Lepidoptera, folívoras externas, são encontradas em baixas frequências e variam entre plantas e ao longo do ano. Este trabalho teve como objetivo analisar os efeitos das variações climáticas e das características das plantas (Miconia, Melastomataceae) na abundância das lagartas. O estudo foi feito no cerrado sensu stricto, Brasília, DF, de maio de 1998 a setembro de 1999. Mensalmente, 100 plantas de cada espécie foram vistoriadas. Todas as lagartas foram coletadas e criadas. Foram correlacionados com os resultados obtidos da abundância de lagartas, os dados climáticos e as seguintes características das plantas: densidade local, distribuição espacial, fenologia, pilosidade e conteúdo nutricional foliar. Menos de 10 por cento das plantas tinham lagartas. As lagartas foram mais frequentes e abundantes em M. pohliana que também foi a espécie de planta com maior densidade na área. A frequência baixa de lagartas em plantas do cerrado é um padrão bastante consistente, assim como o pico de abundância desses imaturos na estação seca. Entretanto, esse pico de abundância não coincide com a produção de folhas em nenhuma das espécies de plantas. A maior densidade local e digestibilidade das folhas de M. pohliana são os fatores que mais explicam a abundância de lagartas nessa espécie.


Subject(s)
Animals , Feeding Behavior/physiology , Lepidoptera/physiology , Melastomataceae/parasitology , Host-Parasite Interactions/physiology , Population Density , Plant Leaves/parasitology , Seasons
13.
Neotrop. entomol ; 39(1): 108-114, Jan.-Feb. 2010. tab, ilus
Article in English | LILACS | ID: lil-540946

ABSTRACT

The leafminer Liriomyza huidobrensis Blanchard is considered a key pest for potatoes in Argentina. Population dynamics and leaf damage caused by the leafminer on seven selected potato processing varieties were assessed at Balcarce during the 2002 and 2003 growing seasons. Adult population dynamic was monitored using yellow sticky traps, while leaf damage (punctures and mines) was assessed using a damage index scale from low to severe. Liriomyza huidobrensis adults were present throughout the growing season and the population increased along crop development. The same was true for all varieties regarding larval damage, being low on early crop stages and severe late in the season. Varieties were grouped in two different categories according to damage scale index. Shepody, Kennebec, Frital and Innovator showed a higher damage index when compared with Santana, Ranger Russet and Russet Burbank, which exhibited a lower damage. Moreover, it could be assumed that damage was related to the foliage greenness, with light green colored varieties (Shepody, Kennebec, Frital and Innovator) being more attractive and affected by L. huidobrensis.


Subject(s)
Animals , Diptera/physiology , Plant Leaves/parasitology , Solanum tuberosum/parasitology , Population Dynamics
14.
Assiut University Bulletin for Environmental Researches. 2010; 13 (1): 35-44
in English | IMEMR | ID: emr-97543

ABSTRACT

This study was conducted throughout whole year of 2009 on lantana hedges bordering farms at cultivated land and newly reclaimed area in Assiut Governorate. The survey revealed the presence of four insect species [Aphis nasturtii Kaltenbach Bemisia tabaci [Gennadius]; Empoasca decipiens Paoli; Scolothrips Iongicornis Priesner], and two mite species [Tetranychus urticae Koch and Amblyseius sp.] on lantana leaves in the two studied areas. Additionally, eleven soil mite species belonging to ten families [Caloglyphus sp. Acaridae; Euphthiracarus sp. Euphthiracaridae; Galumna sp. Galumnidae; Sterroppia sp., Oppiella sp. Oppiidae; Ololaelaps bregetovae Laelapidae; Lasioseius quinisetosus Ascidae; Parasitus sp. Parasitidae; Acaropsella notchi Cheyletidae; Pediculochelus sp. Pediculochelidae and Spinibdeila sp. Bdellidae] were recorded. The population density of A. nasturtii, B. tabaci E. decipiens and Amblyseius sp, was more abundant at newly reclaimed area, while T. urticae and S. longicornis were more abundant at cultivated land. Also, the newly reclaimed area harbored higher numbers of soil mites than that of cultivated land. The Cryptostigmata species exhibited the higher number followed by Astigmata and Mesostigmata, while low numbers of the Prostigmata were recorded in the cultivated land and newly reclaimed area


Subject(s)
Insecta , Plant Leaves/parasitology , Soil/analysis , Insecta , Mite Infestations/epidemiology , Aphids/parasitology , Acaridae/parasitology
15.
Rev. biol. trop ; 57(1/2): 293-302, March-June 2009. ilus
Article in English | LILACS | ID: lil-637719

ABSTRACT

Gall inducing insects most frequently oviposit in young tissues because these tissues have higher metabolism and potential for differentiation. However, these insects may also successfully establish in mature tissues as was observed in the super-host Copaifera langsdorffii. Among C. langsdorffii gall morphotypes, one of the most common is a midrib gall induced by an undescribed species of Cecidomyiidae. Following this ‘host plant and gall-inducing insect’ model, we addressed two questions: 1) Do the age of the tissues alter the gall extended phenotype? 2) Do gall morphological and anatomical features influence the adaptive value of the galling insect? For anatomical and histometrical studies, transverse sections of young and mature, galled and ungalled samples were prepared. Galls in young leaflets presented higher potential for cell division and greater nutritive reserves, whereas galls in mature leaflets perhaps provide more protection against natural predators and desiccation. Host organ age at the time of oviposition may influence plant cell fates and consequently the interpretation of the adaptive value of insect galls. Rev. Biol. Trop. 57 (1-2): 293-302. Epub 2009 June 30.


Subject(s)
Animals , Fabaceae/parasitology , Plant Leaves/parasitology , Plant Tumors/parasitology , Fabaceae/anatomy & histology , Fabaceae/classification , Host-Parasite Interactions , Insecta/physiology , Plant Leaves/anatomy & histology , Plant Leaves/cytology , Time Factors
16.
Neotrop. entomol ; 38(1): 126-132, Jan.-Feb. 2009. ilus, tab
Article in Portuguese | LILACS | ID: lil-510411

ABSTRACT

Avaliou-se a influência da face foliar, do comportamento geotrópico do inseto e do tipo de tricoma foliar sobre a oviposição de Bemisia tabaci (Genn.) biótipo B em folhas de tomateiro. Para avaliação desses efeitos foram realizados vários ensaios nos quais as fêmeas foram confinadas em caixas de acrílico. Folíolos de tomateiro foram fixados no topo e na base das caixas, de tal forma a permitir o acesso dos insetos às faces adaxial e abaxial de maneira isolada e concomitante (com e sem chance de escolha). Os insetos sempre depositaram maior número de ovos quando a superfície foliar se encontrava no topo da caixa e, de maneira geral, preferiram depositar seus ovos na face abaxial dos folíolos. Para avaliar o efeito do tipo de tricoma (glandular e não-glandular) sobre a oviposição de B. tabaci, a face abaxial dos folíolos de tomateiro foi oferecida a cerca de 30 fêmeas para oviposição em cada caixa de acrílico. Foram oferecidos folíolos previamente lavados com etanol a 70 por cento (de forma a eliminar os exsudatos glandulares) e sem lavagem prévia. A maior parte da oviposição ocorreu ao lado dos tricomas não-glandulares, demonstrando que o inseto discrimina o tipo de tricoma.


The objective of this work was to evaluate the influence of the leaf surface, the insect geotropic behavior and the type of foliar trichome on Bemisia tabaci (Genn.) biotype B oviposition on tomato leaves. Bemisia tabaci females were confined in acrylic boxes in which tomato leaflets were fixed at the bottom and top part of the boxes to allow insects to access the leaf surface to be tested (adaxial and/or abaxial) in both no-choice and free choice tests. Oviposition was always higher when the leaf was offered at the top of the box and preferably at the abaxial leaf surface. The effects of leaf trichomes (glandular and non glandular) on B. tabaci oviposition was evaluated by offering the abaxial surface of tomato leaflets to females after a 70 percent ethanol wash to remove glandular exsudates against a control treatment (without a ethanol wash). Oviposition was concentrated mostly near to non glandular trichomes, showing whitefly females can discriminate among the trichomes.


Subject(s)
Animals , Behavior, Animal , Hemiptera/anatomy & histology , Solanum lycopersicum/parasitology , Oviposition , Plant Leaves/parasitology
17.
Braz. j. biol ; 68(4): 831-836, Nov. 2008. graf, tab
Article in English | LILACS | ID: lil-504502

ABSTRACT

Variations in specific foliar mass and water content, nitrogen, soluble carbohydrates and tannins were studied during the growth and maturation processes of the Xylopia aromatica leaves, to determine the effects of such alterations on the herbivory of Stenoma scitiorella caterpillars. This work was carried out in the physiognomy of the typical cerrado of the Parque Estadual de Vassununga, Gleba Pé-de Gigante, Santa Rita do Passa Quatro, São Paulo State, Brazil. While nutritional quality (water and nitrogen) decreases during expansion and maturation of Xylopia aromatica leaves, the chemical (tannins) and physical (sclerophylly) defenses are raised. In agreement with the observations on herbivory, the results support the hypothesis that the reduction in palatability and increase in chemical defenses of Xylopia aromatica leaves account for the caterpillars' preference for young expanding leaves.


Com o objetivo de avaliar os efeitos do crescimento e do amadurecimento de folhas de Xylopia aromatica sob o ataque de lagartas de Stenoma scitiorella, foram estudados a variação da área, massa foliar específica, bem como os teores de água, nitrogênio, hidratos de carbono e taninos durante estes processos. O trabalho foi desenvolvido numa fisionomia de cerrado stricto sensu na Gleba Pé-de-Gigante do Parque Estadual de Vassununga, localizado no município de Santa Rita do Passa Quatro, Estado de São Paulo, Brasil. A expansão e o amadurecimento das folhas de Xylopia aromatica resultaram na redução da qualidade nutricional e no aumento de defesas químicas e físicas. Concordando com as observações realizadas sobre a herbivoria, os resultados permitem supor que a redução na palatabilidade das folhas pode explicar a preferência das lagartas por folhas jovens ainda no início do processo de expansão.


Subject(s)
Animals , Food Preferences/physiology , Lepidoptera/physiology , Plant Leaves/growth & development , Xylopia/growth & development , Plant Leaves/chemistry , Plant Leaves/parasitology , Time Factors , Taste/physiology , Xylopia/chemistry , Xylopia/parasitology
18.
J Environ Biol ; 2008 Mar; 29(2): 249-52
Article in English | IMSEAR | ID: sea-113896

ABSTRACT

Macroinvertebrate colonization and breakdown of Pongamia pinnata and Morinda tinctoria leaves were studied in an astatic pond in Madura College, Madurai. Morinda tinctoria leaves broke down fasterthan the leaves of P. pinnata. Breakdown capacities of astatic pond cannot be attributed to colonization of macroinvertebrates. Instead, microbial processing, and abiotic fragmentation are suggested as factors controlling breakdown rates. Tanypus sp (midgelarva) was abundant in leaf bags during the experimental period. This midge-larva appeared to use litter accumulations as a microhabitat that provided shelter and a rich supply of food in the form of organic matter Their abundance and regular occurrence of two leaves suggest that midge larvae enhance leaf fragmentation and possibly mediate the incorporation of organic matter in pond sediments once the plant tissue is sufficiently macerated.


Subject(s)
Animals , Ecosystem , Fresh Water , India , Invertebrates/growth & development , Millettia/parasitology , Morinda/parasitology , Plant Leaves/parasitology , Time Factors
19.
Rev. bras. entomol ; 52(1): 57-61, 2008. ilus, graf, tab
Article in Portuguese | LILACS | ID: lil-481212

ABSTRACT

Clusia hilariana é uma das espécies de plantas mais abundantes no Parque Nacional, desempenhando um papel importante na dinâmica sucessional desse ecossistema de restinga. Esse trabalho apresenta a composição e aspectos ecológicos das espécies de larvas de mariposas encontradas em C. hilariana. Em 40 plantas, mensalmente vistoriadas, foram obtidas quatorze espécies de lepidópteros. Chloropaschia granitalis foi a espécie de larva mais abundante alimentando-se nessa espécie de planta.


Clusia hilariana is one of the most abundant plant species in the National Park playing important role at the sucessional dynamic of the restinga ecosystem. This paper presents the composition and ecological aspects of caterpillars species found on C. hilariana. From 40 plants monthy inspected, fourteen species of Lepidoptera were obtained. Chloropaschia granitalis (Pyralidae) was the most abundant species feeding on this plant species.


Subject(s)
Animals , Plant Leaves/parasitology , Lepidoptera/growth & development , Lepidoptera/physiology , Tropical Climate , Brazil , Host-Parasite Interactions , Larva
20.
Rev. bras. entomol ; 51(2): 210-216, 2007. ilus, tab, graf
Article in English | LILACS | ID: lil-458098

ABSTRACT

Plant trichomes can difficult the attachment and movement of small insects. Here, we examine the hypothesis that the success on the use of densely haired hosts by two cassidine species is determined by differential morphology and behavior. Larvae of Gratiana graminea (Klug, 1829) and Gratiana conformis (Boheman, 1854) move on the leaf surface of their host, Solanum guaraniticum Hassl by anchoring their tarsungulus on the trichome rays or by inserting the tarsungulus tip directly into epidermis. This kind of movement is only possible due to a similar tarsungulus shape among the species. Tarsungulus growth pattern is also similar between species, being relatively small on the posterior aperture, matching the diameter of the host plant trichome rays. The tarsungulus shape associated with differences on ontogenetic growth and attachment pattern allow these two Cassidinae larvae to efficiently move on the pubescent leaf surface of their host.


Os tricomas foliares podem dificultar a fixação e o movimento de pequenos insetos. Neste trabalho, testamos a hipótese de que o sucesso na exploração de plantas com folhas densamente cobertas por tricomas é determinado pela morfologia e comportamento diferenciados em duas espécies de cassidíneos. As larvas de Gratiana graminea (Klug, 1829) e Gratiana conformis (Boheman, 1854) se movem sobre a superfície foliar de sua hospedeira, Solanum guaraniticum Hassl através do ancoramento de seus tarsúngulos no raio dos tricomas estrelados da planta ou da inserção da ponta desta estrutura diretamente na epiderme. Tais tipos de movimento só são possíveis devido à forma dos tarsúngulos, a qual é similar nas duas espécies. O padrão de crescimento dos tarsúngulos das espécies estudadas é também similar e apresenta-se relativamente menor na abertura posterior, correspondente ao diâmetro dos raios dos tricomas estrelados. A forma dos tarsúngulos, associada às diferenças no seu padrão de crescimento permite às larvas destas duas espécies de Cassidinae se moverem com eficiência sobre a superfície pubescente de sua planta hospedeira.


Subject(s)
Animals , Male , Female , Coleoptera/growth & development , Plant Leaves/anatomy & histology , Plant Leaves/physiology , Plant Leaves/parasitology , Solanum
SELECTION OF CITATIONS
SEARCH DETAIL