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Detection and characterization of Wolbachia infections in natural populations of aphids: is the hidden diversity fully unraveled?

Augustinos, Antonis A.; Santos-Garcia, Diego; Dionyssopoulou, Eva; Moreira, Marta; Papapanagiotou, Aristeidis; Scarvelakis, Marios; Doudoumis, Vangelis; Ramos, Silvia; Aguiar, António F.; Borges, Paulo A. V.; Khadem, Manhaz; Latorre, Amparo; Tsiamis, Geo
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em /12/2011 ENG
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Copyright © 2011 Augustinos et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.; Aphids are a serious threat to agriculture, despite being a rather small group of insects. The about 4,000 species worldwide engage in highly interesting and complex relationships with their microbial fauna. One of the key symbionts in arthropods is Wolbachia, an a-Proteobacterium implicated in many important biological processes and believed to be a potential tool for biological control. Aphids were thought not to harbour Wolbachia; however, current data suggest that its presence in aphids has been missed, probably due to the low titre of the infection and/or to the high divergence of the Wolbachia strains of aphids. The goal of the present study is to map the Wolbachia infection status of natural aphids populations, along with the characterization of the detected Wolbachia strains. Out of 425 samples from Spain, Portugal, Greece, Israel and Iran, 37 were found to be infected. Our results, based mainly on 16S rRNA gene sequencing, indicate the presence of two new Wolbachia supergroups prevailing in aphids...

Consumption of Cinara spp. (Hemiptera, Aphididae) by Cycloneda sanguinea (Linnaeus, 1763) and Hippodamia convergens Guérin-Méneville, 1842 (Coleoptera, Coccinellidae)

Cardoso,Josiane Teresinha; Lázzari,Sonia Maria Noemberg
Fonte: Sociedade Brasileira De Entomologia Publicador: Sociedade Brasileira De Entomologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2003 EN
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Adults and larvae of coccinellids were observed feeding on populations of the giant conifer aphids Cinara spp. on Pinus spp., in Southern Brazil. The objective of this research is to evaluate the consumption capacity of Cycloneda sanguinea (Linnaeus, 1763) and Hippodamia convergens Guérin-Méneville, 1842 (Coleoptera, Coccinellidae) on these aphid species, in order to obtain information for biological control programs. Ten larvae of each predator species were fed with aphids of small size (nymphs of 1st and 2nd instars), and 10 with aphids of medium size (nymphs of 3rd and 4th instars), maintained under 15ºC, 20ºC and 25ºC, 12 h photophase and 70 ± 10% relative humidity. The aphids were counted every 24 hours, replacing those that were consumed. The total consumption of Cinara by the larvae of C. sanguinea was not statistically different at the three temperatures: 325.5; 322.2 and 324.8 of small aphids and 121.3; 140.4 and 109.9 of medium ones, respectively at 15ºC, 20ºC and 25ºC. The consumption by H. convergens was higher than by C. sanguinea and increased noticeably with temperature: 444 aphids at 15ºC; 491.3 at 20ºC and 513.3 at 25ºC, considering the small aphids, and 187.1; 205.1 and 216.6 of medium aphids at the three temperatures. The small aphids weigh about half as much as medium ones and were preferred by all larval instars probably because they are easier to manipulate than the large ones. Both predators...

Predatory behavior of Pseudodorus clavatus (Diptera, Syrphidae) on aphids tended by ants

Bächtold,Alexandra; Del-Claro,Kleber
Fonte: Sociedade Brasileira De Entomologia Publicador: Sociedade Brasileira De Entomologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2013 EN
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Predatory behavior of Pseudodorus clavatus (Diptera, Syrphidae) on aphids tended by ants. In this study, we examined the interactions between myrmecophilous aphids, their ant-guards and a predatory syrphid species, Pseudodorus clavatus (F.). Larvae of this predator were found in the colonies of three aphid species: Aphis gossypii, A. spiraecola and Toxoptera sp., which were tended by eight ant species, especially Camponotus. Hoverfly larvae managed to infiltrate the aphid colonies and consume nymphs. Predator larvae exhibited inconspicuous movements and were not detected by ants which were commonly observed touching and antennating the larvae they come into contact. These results suggest that behavioral and chemical cues are involved in the infiltration and on the successful predation of syrphids upon aphids.

Richness and diversity of aphids (Homoptera, Aphididae) along an altitudinal gradient in the Serra do Mar, Paraná, Brazil

Lazzarotto,Crisleide Maria; Lázzari,Sonia Maria Noemberg
Fonte: Sociedade Brasileira de Zoologia Publicador: Sociedade Brasileira de Zoologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/1998 EN
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The lack of bioecological studies on aphids in regions with complex floristic and faunistic structure, such as the Atlantic Tropical Rain Forest, lead to the initiation of this research. The objectives were to determine species richness and diversity of aphids and to investigate the influence of altitude and environmental perturbations on aphid populations. The collections were made with yellow pan traps at 11 sites with altitudes from -10 m to 1000 m above sea level (a.s.l.), in the Serra do Mar, Paraná, Brazil, from December 1993 to December 1994. Richness and diversity of aphids were greatest at 85 m a.s.l. This site was characterized by three distinct floral communities: primary vegetation, secondaiy vegetation in successional stages, and secondary vegetation subject to regular mowing. No pattern in the number or kinds of species could be established along the altitudinal gradient. These results, indicate that several factors interact, but especially floristic composition and climatic conditions, to determine aphidofauna richness and diversity in this region of the Atlantic Tropical Rain Forest.

Ants defend aphids against lethal disease

Nielsen, Charlotte; Agrawal, Anurag A.; Hajek, Ann E.
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
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27.43%
Social insects defend their own colonies and some species also protect their mutualist partners. In mutualisms with aphids, ants typically feed on honeydew produced by aphids and, in turn guard and shelter aphid colonies from insect natural enemies. Here we report that Formica podzolica ants tending milkweed aphids, Aphis asclepiadis, protect aphid colonies from lethal fungal infections caused by an obligate aphid pathogen, Pandora neoaphidis. In field experiments, bodies of fungal-killed aphids were quickly removed from ant-tended aphid colonies. Ant workers were also able to detect infective conidia on the cuticle of living aphids and responded by either removing or grooming these aphids. Our results extend the long-standing view of ants as mutualists and protectors of aphids by demonstrating focused sanitizing and quarantining behaviour that may lead to reduced disease transmission in aphid colonies.

Detection and Characterization of Wolbachia Infections in Natural Populations of Aphids: Is the Hidden Diversity Fully Unraveled?

Augustinos, Antonis A.; Santos-Garcia, Diego; Dionyssopoulou, Eva; Moreira, Marta; Papapanagiotou, Aristeidis; Scarvelakis, Marios; Doudoumis, Vangelis; Ramos, Silvia; Aguiar, Antonio F.; Borges, Paulo A. V.; Khadem, Manhaz; Latorre, Amparo; Tsiamis, Geor
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 13/12/2011 EN
Relevância na Pesquisa
27.39%
Aphids are a serious threat to agriculture, despite being a rather small group of insects. The about 4,000 species worldwide engage in highly interesting and complex relationships with their microbial fauna. One of the key symbionts in arthropods is Wolbachia, an α-Proteobacterium implicated in many important biological processes and believed to be a potential tool for biological control. Aphids were thought not to harbour Wolbachia; however, current data suggest that its presence in aphids has been missed, probably due to the low titre of the infection and/or to the high divergence of the Wolbachia strains of aphids. The goal of the present study is to map the Wolbachia infection status of natural aphids populations, along with the characterization of the detected Wolbachia strains. Out of 425 samples from Spain, Portugal, Greece, Israel and Iran, 37 were found to be infected. Our results, based mainly on 16S rRNA gene sequencing, indicate the presence of two new Wolbachia supergroups prevailing in aphids, along with some strains belonging either to supergroup B or to supergroup A.

Alternaria toxin-induced resistance against rose aphids and olfactory response of aphids to toxin-induced volatiles of rose plants*

Yang, Fa-zhong; Li, Li; Yang, Bin
Fonte: Zhejiang University Press Publicador: Zhejiang University Press
Tipo: Artigo de Revista Científica
Publicado em /02/2012 EN
Relevância na Pesquisa
27.39%
The search for active toxins for managing weeds or plant diseases is believed to be a promising avenue of investigation. However, the effects of Alternaria toxins on insects have just begun to be investigated. Bioactivities of toxins from four strains of Alternaria alternata on Rosa chinensis and rose aphid Macrosiphum rosivorum were tested in the present study. At a concentration of 50.0 μg/ml, the crude extract (toxin) of strain 7484 was found not to be harmful to rose plants with excised leaf-puncture method (P≥0.079), and rose plants showed enhanced resistance to rose aphids when this Alternaria toxin was sprayed on the plants (P≤0.001). However, this toxin caused no detrimental effects on aphids in insecticidal bioassay at a concentration of 10.0 to 160.0 μg/ml (P≥0.096). Therefore, the Alternaria toxin had significantly induced the resistance of rose plants against rose aphids, demonstrating that the resistance mechanism triggered by the Alternaria toxin in the rose plant may also be used by the plant to defend itself against insects. Further bioassays aimed to discover the olfactory responses of aphids to the toxin-induced volatiles of host plants. The aphids were significantly more attracted to both volatiles emitted and collected from control rose plants than to both volatiles emitted and collected from the toxin-treated rose plants (P≤0.014). This result showed that the toxin-induced resistance related to the volatile changes of host plants.

Shallot Aphids, Myzus ascalonicus, in Strawberry: Biocontrol Potential of Three Predators and Three Parasitoids

Enkegaard, Annie; Sigsgaard, Lene; Kristensen, Kristian
Fonte: University of Wisconsin Library Publicador: University of Wisconsin Library
Tipo: Artigo de Revista Científica
Publicado em 04/09/2013 EN
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The parasitization capacity of 3 parasitoids and the predation capacity of 3 predators towards the shallot aphid, Myzus ascalonicus Doncaster (Homoptera: Aphididae), on strawberry, Fragaria x ananassa Duchesne (Rosales: Rosaceae) cv. Honeoye, were examined in laboratory experiments. In Petri dish assays, both Aphidius colemani Viereck (Hymenoptera: Aphidiidae) and A. ervi Haliday readily stung shallot aphids, with no significant difference in stinging frequency between the two species. A. ervi induced a significantly higher mortality (79.0 ± 7.2%) in terms of stung aphids compared with A. colemani (55.3 ± 4.1%); however, only a minor fraction (2.7 ± 1.8% and 7.1 ± 3.1%, respectively) of the killed aphids resulted in formation of mummies, presumably due to a physiological response to parasitism. The low percentage of mummification precludes the use of either Aphidius species in anything but inundative biocontrol. In similar set-ups, Aphelinus abdominalis (Dalman) (Hymenoptera: Aphelinidae) killed almost half (49.6 ± 5.3%) of the exposed aphids through host feeding. In addition, 23.2 ± 7.3% of non-host-fed aphids developed into mummified aphids, and 38.1 ± 13.2% of non-host-fed aphids died from other parasitoid-induced causes. However...

The Green Lacewing, Chrysoperla carnea: Preference between Lettuce Aphids, Nasonovia ribisnigri, and Western Flower Thrips, Frankliniella occidentalis

Shrestha, Govinda; Enkegaard, Annie
Fonte: University of Wisconsin Library Publicador: University of Wisconsin Library
Tipo: Artigo de Revista Científica
Publicado em 30/09/2013 EN
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This study investigated the prey preference of 3rd instar green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae), between western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and lettuce aphids, Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae) in laboratory experiments at 25 ± 1° C and 70 ± 5% RH with five prey ratios (10 aphids:80 thrips, 25 aphids:65 thrips, 45 aphids:45 thrips, 65 aphids:25 thrips, and 80 aphids:10 thrips). Third instar C. carnea larvae readily preyed upon both thrips and aphids, with thrips mortality varying between 40 and 90%, and aphid mortality between 52 and 98%. Chrysoperla carnea had a significant preference for N. ribisnigri at two ratios (10 aphids:80 thrips, 65 aphids:25 thrips), but no preference for either prey at the other ratios. There was no significant linear relationship between preference index and prey ratio, but a significant intercept of the linear regression indicated an overall preference of C. carnea for aphids with a value of 0.651 ± 0.054. The possible implications of these findings for control of N. ribisnigri and F. occidentalis by C. carnea are discussed.

Shallot aphids, Myzus ascalonicus, in strawberry: Biocontrol potential of three predators and three parasitoids

Enkegaard, Annie; Sigsgaard, Lene; Kristensen, Kristian
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
27.54%
The parasitization capacity of 3 parasitoids and the predation capacity of 3 predators towards the shallot aphid, Myzus ascalonicus Doncaster (Homoptera: Aphididae), on strawberry, Fragaria x ananassa Duchesne (Rosales: Rosaceae) cv. Honeoye, were examined in laboratory experiments. In Petri dish assays, both Aphidius colemani Viereck (Hymenoptera: Aphidiidae) and A. ervi Hal-iday readily stung shallot aphids, with no significant difference in stinging frequency between the two species. A. ervi induced a significantly higher mortality (79.0 ± 7.2%) in terms of stung aphids compared with A. colemani (55.3 ± 4.1%); however, only a minor fraction (2.7 ± 1.8% and 7.1 ± 3.1%, respectively) of the killed aphids resulted in formation of mummies, presumably due to a physiological response to parasitism. The low percentage of mummification precludes the use of either Aphidius species in anything but inundative biocontrol. In similar set-ups, Ap-helinus abdominalis (Dalman) (Hymenoptera: Aphelinidae) killed almost half (49.6 ± 5.3%) of the exposed aphids through host feeding. In addition, 23.2 ± 7.3% of non-host-fed aphids developed into mummified aphids...

The green lacewing, Chrysoperla carnea: Preference between lettuce aphids, Nasonovia ribisnigri, and western flower thrips, Frankliniella occidentalis

Shrestha, Govinda; Enkegaard, Annie
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
27.52%
This study investigated the prey preference of 3rdinstar green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae), between western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and lettuce aphids, Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae) in laboratory experiments at 25 ± 1º C and 70 ± 5% RH with five prey ratios (10 aphids:80 thrips, 25 aphids:65 thrips, 45 aphids:45 thrips, 65 aphids:25 thrips, and 80 aphids:10 thrips). Third instar C. carnea larvae readily preyed upon both thrips and aphids, with thrips mortality varying between 40 and 90%, and aphid mortality between 52 and 98%. Chrysoperla carnea had a significant preference for N. ribisnigri at two ratios (10 aphids:80 thrips, 65 aphids:25 thrips), but no preference for either prey at the other ratios. There was no significant linear relationship between preference index and prey ratio, but a significant intercept of the linear regression indicated an overall preference of C. carnea for aphids with a value of 0.651 ± 0.054. The possible implications of these findings for control of N. ribisnigri and F. occidentalis by C. carnea are discussed.

Binomial Sequential Sampling Methods for Cereal Aphids in Small Grains

Elliott, N. C.; Kieckhefer, R. W.; Walgenbachi, D. D.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
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Seventy-one samples of 200 to 400 tillers each were taken from small grain fields. An equation used to relate the proportion of infested tillers to the mean number of aphids per tiller fit the data well (r2 = 0.98). Although the equation was developed from pooled counts of four species of cereal aphids (Schizaphis graminum (Rondani), Sitobion avenae (F.), Rhopalosiphum padi (L.), and R. maidis (Fitch)), it described the relationship between the proportion of infested tillers and mean number of aphids per tiller adequately for each species individually. When predictions from the equation were compared with independent data, the predicted and actual numbers of aphids per tiller were similar. Required sample sizes for estimation of the mean number of aphids per tiller with fixed average levels of precision (standard error /mean) were determined. Required sample sizes to achieve a precision level of 0.15 ranged from a low of approximately 110 tillers for intermediate aphid populations to >500 tillers for low and high aphid populations. A truncated sequential sampling plan was developed. Using this plan, from 25 to 100 tillers are inspected for the presence or absence of cereal aphids. The average number of tillers inspected to arrive at a control decision ranged from 25 to 76 tillers depending on aphid population density. The frequency of decision errors was high (approximately 0.9) for populations near the action threshold (12.5 aphids/tiller)...

As plantas bioativas como estrat??gia ?? transi????o agroecol??gica na agricultura familiar: an??lise sobre a utiliza????o emp??rica e experimental de extratos bot??nicos no manejo de af??deos em hortali??as; Plants as bioactive strategy to agroecological transition on family farms: analysis of the empirical and experimental use of botanical extracts in the management of aphids in vegetables

LOVATTO, Patr??cia Braga
Fonte: Universidade Federal de Pelotas; Agricultura familiar; Programa de P??s-Gradua????o em Sistemas de Produ????o Agr??cola Familiar; UFPel; BR Publicador: Universidade Federal de Pelotas; Agricultura familiar; Programa de P??s-Gradua????o em Sistemas de Produ????o Agr??cola Familiar; UFPel; BR
Tipo: Tese de Doutorado Formato: application/pdf
POR
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Knowledge about the use of bioactive plants for insect management has assisted in developing methods less harmful to the environment and human health, becoming a viable and environmentally sound strategy to be incorporated into agricultural production systems family that aims to sustainability. Thus, the active principles of plants can act in crop protection by acting as repellents, attractive and / or insecticides, representing a low-cost technology and reduced environmental impact, made from the recovery and maintenance of popular knowledge. Given these assumptions the research presented here was to order, identify, classify and contextualize the use of bioactive plants, used for the management of agroecossitemas by farmers in ecological basis of the Territory South Zone of RS, combining elements of research in ethnobotany research data experimental to legitimize the use of botanicals in the management of aphids on vegetable crops. Serving up the research participant and the phenomenological approach as qualitative tools for ethnobotanical research conducted with 33 farmers in ecological basis linked to the Cooperative Ecological and ARPA South-South, it was possible to infer the empirical use of 24 different plant species for management bioactive agroecosystems. Thus...

Occurrence and parasitism of aphids (Hemiptera: Aphididae) on cultivars of irrigated oat (Avena spp.) in São Carlos, Brazil

Ronquim,Júlio Cesar; Pacheco,Josué Marques; Ronquim,Carlos Cesar
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2004 EN
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The interactions between aphids and their Hymenopteran parasitoids on irrigated oats as well as the response of different cultivars of cereals regarding the resistance to these aphids and the influence on the host/parasitoid relationships were studied during two years in São Carlos, Brazil. Rhopalosiphum padi (L.) was the predominant aphid observed throughout the study, while the other species were rarely found. Five species of parasitic Hymenoptera were found: three primary parasitoids, Lysiphlebus testaceipes (Cresson), Aphidius colemani (Viereck) and Diaeretiella rapae (M'Intosh) and two hyperparasitoids, Syrphophagus aphidivorus (Myer) and Alloxysta brassicae (Ashmead). The UPF 86081 cultivar presented significant results regarding lower Rhopalosiphum padi contamination and higher aphid parasitism rates than those observed on some other cultivars. No significant effect on the percentage variation of parasitoid emergence on the mummified aphids was observed throughout this study.

Natural enemies associated to aphids in peach orchards in Araucária, Paraná, Brazil

Schuber,JM.; Monteiro,LB.; Almeida,LM.; Zawadneak,MAC.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2012 EN
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Natural enemies of the Class Insecta are important agents in the balance of aphid populations and an alternative to using insecticides to control these insects. The aim of this study was to identify the species of natural enemies associated with aphids present in peach orchards and observe the efficiency of capturing different sampling methods. The experiment was conducted from July, 2005 to September, 2006 in six peach orchards 'Chimarrita', in Araucária, PR, Brazil. The samples were taken by visual analysis in peach plants and weeds, yellow pan traps, sticky traps and funnels. Predator species were identified: Cryptolaemus montrouzieri, Cycloneda pulchella, Cycloneda sanguinea, Eriopis connexa, Harmonia axyridis, Hippodamia convergens and Scymnus sp. (Coleoptera, Coccinellidae), Allograpta sp., Palpada sp. and Toxomerus sp. (Diptera, Syrphidae) and Chrysoperla sp. (Neuroptera, Chrysopidae) and the parasitoids: Diaretiella rapae, Opius sp. and Praon sp (Braconidae). Examples of Encyrtidae and Eulophidae await identification. Chrysoperla sp. was a less abundant species. There were no statistically significant differences between the different sampling methods tested.

Evaluación del sistema planta hospedera-huésped alternativo como estrategia para el control biológico de pulgones (Hemiptera: Aphididae) en sistemas de producción hortícola en cultivos protegidos; Evaluation of an alternative host plant-phytophagous system for biological control of aphids (Hemiptera: aphididae) in protected vegetable crops

Andorno, Andrea Verónica
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2012 SPA
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Los áfidos constituyen una de las plagas de mayor importancia económica sobre una gran variedad de cultivos. El control biológico por conservación utilizando plantas hospederas y fitófagos huéspedes alternativos ha sido exitosamente utilizado en el manejo de áfidos plaga. Esta modalidad consiste en el empleo de especies vegetales hospederas de herbívoros inócuos para el cultivo de interés pero que son utilizados por los enemigos naturales de la plaga como huéspedes alternativos. El objetivo de esta tesis fue evaluar el empleo de este sistema como estrategia para el control del áfido plaga, Myzus persicae por el parasitoide Aphidius colemani en cultivos hortícolas (rúcula y pimiento). Los principales aportes de esta tesis han sido: Conocimiento de las asociaciones áfidos - enemigos naturales parasitoides en cultivos hortícolas y plantas hospederas no cultivadas. Conocimiento de la biología y parámetros poblacionales de M. persicae sobre el cultivo de rúcula. Conocimiento de los atributos biológicos y de la preferencia del parasitoide A. colemani sobre las asociaciones cultivo- huésped plaga y planta hospedera alternativa- áfido alternativo, R. padi. Conocimientos sobre la compatibilidad de empleo de insecticidas y el parasitoide A. colemani. Evaluación del sistema planta hospedera – huésped alternativo para el control biológico de M. persicae por el parasitoide A. colemani.; Aphids are a common problem on a wide variety of crops. Alternative host plant - phytophagous systems has been successfully applied in conservation biological control for aphid pests. The use of alternative host plant – phytophagous provides an alternative suitable food resource for those natural enemies controlling the target pest with no threat for the crop of interest. The aim of this thesis was to evaluate the use of the alternative host plant - aphid - parasitoid system (oat - Rhopalosiphum padi - Aphidius colemani) as a strategy for aphid pest control in vegetable crop systems (arugula and pepper). The most important contributions from this thesis are: Knowledge of the relationships between aphids - natural enemies parasitoids associated to vegetable crops and uncultivated host plants. Knowledge of the biology of the aphid pest M. persicae in arugula. Knowledge on the biology and host preference of the aphid parasitoid A. colemani. Knowledge on the side effect of pesticides on A. colemani. Evaluation of the “alternative host plant- phytophagous system” as a biological control strategy of M. persicae by the aphid parasitoid A. colemani; Fill:Andorno...

Transient expression of homologous hairpin RNA interferes with PVY transmission by aphids

Vargas, Marisol; Martínez-García, Belén; Díaz-Ruíz, José Ramón; Tenllado, Francisco
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artículo Formato: 918366 bytes; application/pdf
ENG
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Hairpin RNAs have been used to confer resistance to viruses in plants through RNA silencing. However, it has not been demonstrated that RNA silencing was effective against inoculation by aphids of non-persistently transmitted viruses, the major route of plant virus spread in nature. As a proof-of-principle strategy, we made use of Agrobacterium tumefaciens to transiently express a hairpin RNA homologous to Potato virus Y (PVY) in plant tissues. A complete and specific interference with aphid transmission of PVY was achieved by inducers of RNA silencing, as demonstrated by specific siRNAs accumulation in agroinfiltrated tissues. To our knowledge, this is the first report of successful interference with non-persistent transmission of a plant virus using RNA interference.; MV was supported by doctoral fellowships from CONICYT-BID (Chile). This work was supported by grant BIO2006-10944 from CICYT-MEC (Spain).; Peer reviewed

Activity of alatae aphids landing on open-field pepper crops in Spain; Aktivität und Vorkommen geflügelter Blattläuse auf Freilandpaprika in Spanien

Perez, P.; Duque, M.; Collar, J. L.; Avilla, C.; Fereres, Alberto
Fonte: Éditions Eugen Ulmer Publicador: Éditions Eugen Ulmer
Tipo: Artículo Formato: 4085 bytes; image/gif
ENG
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Horizontal mosaic-green-tile traps were placed in various pepper-growing areas of Spain: Aranjuez and Arganda del Rey (Madrid), Balboa (Badajoz), Cadreita (Pamplona), Mendavia and Sartaguda (Logroño), Montañana (Zaragoza), Pueblo Nuevo (Valencia) and Torrepacheco (Murcia). These mosaic-greentraps resembled much better the pepper canopy than the commonly used yellow water traps, as indicated by absorbance spectrophotometry. Sampling was extended throughout the pepper crop cycle during 1990, 1991 and 1992. Over that time, 14,363 aphids, belonging to 99 species/taxa were captured. Aphis was the principal genus captured: 57.5 % of the total (17 % belonging to the species Aphis fabae (Scopoli)). Other abundant species were: Myzus (Nectarosiphon) persicae (Sulzer) (7.46 %), Diuraphis noxia (Mordvilko) (5.23 %), Brachycaudus spp. (3.73 %), Sitobion avenae (F.) (2.51 %), Macrosiphum euphorbiae (Thomas) (2.46 %), Rhopalosiphum spp. (2.20 %) and Therioaphis spp. (1.99 %). The species included in the genus Aphis were the most abundant in all the regions sampled, although M. (N.) persicae was also predominant in the Zaragoza and Pamplona region, and D. noxia was frequently found in the Madrid region. A first aphid peak was observed soon after transplanting (May–June) in most of the regions and years sampled.; Horizontale mosaikgrüne Farbfallen wurden in verschiedenen Paprika-Anbaugebieten in Spanien aufgestellt: Aranjuez und Arganda del Rey (Madrid)...

Molecular evolution of aphids and their primary (buchnera sp.) and secondary endosymbionts: implications for the role of symbiosis in insect evolution

Sabater-Muñoz, Beatriz; Ham, Roeland C.H.J. van; Martínez-Torres, David; Silva-Moreno, Francisco; Latorre-Castillo, Amparo; Moya-Simarro, Andrés
Fonte: Asociación Interciencia Publicador: Asociación Interciencia
Tipo: Artículo
ENG
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Aphids maintain an obligate, endosymbiotic association with Buchnera sp., a bacterium closely related to Escherichia coli. Bacteria are housed in specialized cells of organ-like structures called bacteriomes in the hemocoel of the aphid and are maternally transmitted. Phylogenetic studies have shown that the association had a single origin, dated about 200-250 million years ago, and that host and endosymbiont lineages have evolved in parallel since then. However, the pattern of deepest branching within the aphid family remains unsolved, which thereby hampers an appraisal of, for example, the role played by horizontal gene transfer in the early evolution of Buchnera. The main role of Buchnera in this association is the biosynthesis and provisioning of essential amino acids to its aphid host. Physiological and metabolic studies have recently substantiated such nutritional role. In addition, genetic studies of Buchnera from several aphids have shown additional modifications, such as strong genome reduction, high A+T content compared to free-living bacteria, differential evolutionary rates, a relative increase in the number of non-synonymous substitutions, and gene amplification mediated by plasmids. Symbiosis is an active process in insect evolution as revealed by the intermediate values of the previous characteristics showed by secondary symbionts compared to free-living bacteria and Buchnera.; The authors thank the Servicio Central de Soporte a la Investigación Científica (Universitat de València) for bioinformatics and sequencing facilities. The work has been supported by grants GV-3216/95 from Generalitat Valenciana (Spain)...

Molecular evolution of aphids and their primary (buchnera sp.) and secondary endosymbionts: implications for the role of symbiosis in insect evolution

Sabater,Beatriz; van Ham,Roeland C.H.J; Martínez-Torres,David; Silva,Francisco; Latorre,Amparo; Moya,Andrés
Fonte: ASOCIACIÓN INTERCIENCIA Publicador: ASOCIACIÓN INTERCIENCIA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2001 EN
Relevância na Pesquisa
37.15%
Aphids maintain an obligate, endosymbiotic association with Buchnera sp., a bacterium closely related to Escherichia coli. Bacteria are housed in specialized cells of organ-like structures called bacteriomes in the hemocoel of the aphid and are maternally transmitted. Phylogenetic studies have shown that the association had a single origin, dated about 200-250 million years ago, and that host and endosymbiont lineages have evolved in parallel since then. However, the pattern of deepest branching within the aphid family remains unsolved, which thereby hampers an appraisal of, for example, the role played by horizontal gene transfer in the early evolution of Buchnera. The main role of Buchnera in this association is the biosynthesis and provisioning of essential amino acids to its aphid host. Physiological and metabolic studies have recently substantiated such nutritional role. In addition, genetic studies of Buchnera from several aphids have shown additional modifications, such as strong genome reduction, high A+T content compared to free-living bacteria, differential evolutionary rates, a relative increase in the number of non-synonymous substitutions, and gene amplification mediated by plasmids. Symbiosis is an active process in insect evolution as revealed by the intermediate values of the previous characteristics showed by secondary symbionts compared to free-living bacteria and Buchnera.