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1.
Sci Rep ; 14(1): 1076, 2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212511

RESUMO

Egg deposition by herbivorous insects is well known to elicit defensive plant responses. Our study aimed to elucidate the insect and plant species specificity of these responses. To study the insect species specificity, we treated Arabidopsis thaliana with egg extracts and egg-associated secretions of a sawfly (Diprion pini), a beetle (Xanthogaleruca luteola) and a butterfly (Pieris brassicae). All egg extracts elicited salicylic acid (SA) accumulation in the plant, and all secretions induced expression of plant genes known to be responsive to the butterfly eggs, among them Pathogenesis-Related (PR) genes. All secretions contained phosphatidylcholine derivatives, known elicitors of SA accumulation and PR gene expression in Arabidopsis. The sawfly egg extract did not induce plant camalexin levels, while the other extracts did. Our studies on the plant species specificity revealed that Solanum dulcamara and Ulmus minor responded with SA accumulation and cell death to P. brassicae eggs, i.e. responses also known for A. thaliana. However, the butterfly eggs induced neoplasms only in S. dulcamara. Our results provide evidence for general, phosphatidylcholine-based, egg-associated elicitors of plant responses and for conserved plant core responses to eggs, but also point to plant and insect species-specific traits in plant-insect egg interactions.


Assuntos
Arabidopsis , Borboletas , Besouros , Himenópteros , Animais , Oviposição , Borboletas/fisiologia , Himenópteros/fisiologia , Arabidopsis/genética , Ácido Salicílico , Fosfatidilcolinas
2.
J Econ Entomol ; 115(5): 1545-1550, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-35934883

RESUMO

Palmistichus elaeisis Delvare and LaSalle 1993 (Hymenoptera: Eulophidae) and neem oil are two control alternatives for the integrated management of defoliating lepidopterans. The aim of this study was to evaluate the acute and chronic toxicity of neem oil compared to the synthetic insecticide deltamethrin, on the endoparasitoid P. elaeisis, in generations F0, F1, F2, and F3. Females of P. elaeisis were exposed to neem solutions at concentrations of 0, 1.87, 3.75, 7.50, 15.00, 30.00, and 60.00 mg ml-1, to determine the dose-response relationship and estimate the neem LC50. The sublethal effects on the parasitoid P. elaeisis in generations F0 to F3 were evaluated with these same concentrations of neem and 0.033 mg ml-1 of deltamethrin. The neem LC50 was estimated at 3.92 mg ml-1. The LC50 for P. elaeisis is 3.83 times lower than that recommended by the neem manufacturer for pest control, demonstrating high acute toxicity to this natural enemy. The chronic toxicity of both the commercial dose and those below it to P. elaeisis caused low sublethal effects. The correct concentration of neem oil in pest control is important, and its use should be performed with caution in integrated pest management programs using the endoparasitoid P. elaeisis to avoid causing interference between the two pest control techniques.


Assuntos
Himenópteros , Inseticidas , Animais , Feminino , Glicerídeos , Himenópteros/fisiologia , Inseticidas/toxicidade , Nitrilas , Pupa , Piretrinas , Terpenos
3.
Phytochemistry ; 203: 113350, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35973612

RESUMO

Defense-related metabolome traits in pine species after infestation by Sirex noctilio are largely unknown, despite, in most cases, trees being overwhelmed. Using LC-MS-based untargeted metabolomics, we revealed the systemic metabolic changes induced by this insect in 14-year-old Pinus radiata trees, the most affected species worldwide. An immediate metabolome alteration was expressed in needles after infestation, including the up-regulation of flavonols, flavan-3-ols, oxyneolignans, auxins, proline, and tryptophan, among others. The flavan-3-ols (catechin and procyanidin B1) suggested a rapidly induced photoprotection mechanism aided by diverting proline as an alternative substrate for respiration to compensate for the progressive chlorosis that degrades photosystems. Meanwhile, glutathione, glutamate, and ascorbate levels significantly dropped in needles, which may indicate the critical oxidative stress that trees had to face since the onset of the infestation. They were not fully replenished after long-term infestation, and redox homeostasis was probably not achieved, compromising tree survival. Nevertheless, a huge auxins overexpression detected in needles throughout the infestation may reflect tolerance against the premature senescence caused by the woodwasp venom. In contrast, the metabolome of wood tissues remained initially unchanged, although it seems to collapse after three months. Overall, the metabolomics strategy adopted in this work evidenced its usefulness in uncovering the fundamental roles of plants' chemical defense that govern interactions with specific stressors.


Assuntos
Catequina , Himenópteros , Pinus , Animais , Flavonóis , Glutamatos , Glutationa , Himenópteros/fisiologia , Ácidos Indolacéticos , Prolina , Árvores , Triptofano
4.
Evolution ; 74(5): 859-870, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32187651

RESUMO

Hutchinson's ecological theater and evolutionary play is a classical view of evolutionary ecology-ecology provides a template in which evolution occurs. An opposing view is that ecological and evolutionary changes are like two actors on a stage, intertwined by density and frequency dependence. These opposing views correspond to hard and soft selection, respectively. Although often presented as diametrically opposed, both types of selection can occur simultaneously, yet we largely lack knowledge of the relative importance of hard versus soft selection in the wild. I use a dataset of 3000 individual gall makers from 15 wild local populations over 5 years to investigate the hardness of selection. I show that enemy attack consistently favors some gall sizes over others (hard selection) but that these biases can be fine-tuned by density and frequency dependence (soft selection). As a result, selection is hard and soft in roughly equal measures, but the importance of each type varies as species interactions shift. I conclude that eco-evolutionary dynamics should occur when a mix of hard and soft selection acts on a population. This work contributes to the rapprochement of disparate views of evolutionary ecology-ecology is neither a rigid theater nor a flexible actor, but instead embodies components of both.


Assuntos
Dípteros/fisiologia , Dípteros/parasitologia , Himenópteros/fisiologia , Tumores de Planta/etiologia , Seleção Genética , Solidago/genética , Animais , Ontário , Oviposição , Dinâmica Populacional , Solidago/fisiologia
5.
Neotrop Entomol ; 49(2): 171-178, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31820338

RESUMO

Many hymenopteran parasitoids are known as biocontrol agents, such as Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae), which is known to parasitize larvae and pupae of coleopteran pests including Lasioderma serricorne (Fabricius) (Coleoptera: Ptinidae). The success of these parasitoids is related to their searching ability, which is mediated through chemical stimuli of the habitat, food, and the progeny of the host itself. This study aimed to assess the chemotaxic responses of A. calandrae comparing the reproductive state of the insects and the experience of wasp females, to different development stages (larvae and pupae) and the presence or absence of the host diet. The chemotaxic responses of A. calandrae individuals at 2 to 4 days old were assessed in a "Y" type olfactometer. Virgin and paired females (without and with previous experience of parasitism) were exposed to larvae of last instar contrasted with pupae and to the diet of L. serricorne. Both virgin and mated males were tested only for diet. Virgin females showed a preference for the diet in contrast to the larvae and to the pupae in contrast to the diet. Paired females without experience choose larvae over diet and made no distinction between pupae and diet. Experienced mated females showed preference for the host to which it had access before, instead of any other alternative option, indicating that there may be changes in the preference through learning.


Assuntos
Quimiotaxia , Besouros/química , Himenópteros/fisiologia , Odorantes , Animais , Besouros/parasitologia , Dieta , Feminino , Larva , Masculino , Pupa
6.
Channels (Austin) ; 13(1): 264-286, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31237176

RESUMO

Calcium entry is central to the functional processes in mast cells and basophils that contribute to the induction and maintenance of inflammatory responses. Mast cells and basophils express an array of calcium channels, which mediate responses to diverse stimuli triggered by small bioactive molecules, physicochemical stimuli and immunological inputs including antigens and direct immune cell interactions. These cells are also highly responsive to certain venoms (such as Hymenoptera envenomations), which cause histamine secretion, cytokine release and an array of pro-inflammatory functional responses. There are gaps in our understanding of the coupling of venom exposure to specific signaling pathways such as activation of calcium channels. In the present study, we performed a current survey of a model mast cell line selected for its pleiotropic responsiveness to multiple pro-inflammatory inputs. As a heterogenous stimulus, Hymenoptera venom activates multiple classes of conductance at the population level but tend to lead to the measurement of only one type of conductance per cell, despite the cell co-expressing multiple channel types. The data show that ICRAC, IARC, and TRPV-like currents are present in the model mast cell populations and respond to venom exposure. We further assessed individual venom components, specifically secretagogues and arachidonic acid, and identified the conductances associated with these stimuli in mast cells. Single-cell calcium assays and immunofluorescence analysis show that there is heterogeneity of channel expression across the cell population, but this heterogeneity does not explain the apparent selectivity for specific channels in response to exposure to venom as a composite stimulus.


Assuntos
Venenos de Artrópodes/farmacologia , Mordeduras e Picadas/imunologia , Himenópteros/fisiologia , Mastócitos/imunologia , Animais , Venenos de Artrópodes/imunologia , Venenos de Artrópodes/toxicidade , Histamina/imunologia , Humanos , Himenópteros/imunologia , Mastócitos/efeitos dos fármacos , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/imunologia
7.
Parasite ; 26: 8, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30794147

RESUMO

Quadrastichus mendeli Kim & La Salle, a parasitoid of Leptocybe invasa Fisher & La Salle, is a uniparental species. This study assessed the biological traits of Q. mendeli in the laboratory at a temperature of 27 ± 1 °C. Diets had a highly significant effect on the mean longevity of female Q. mendeli. Feeding honey solution prolonged the mean longevity of the parasitoid to 4.80 days. The estimated 50% survival period was 3 days. The mean potential fecundity in all ages was 8.85 eggs per female. Age had a highly significant effect on the mean egg load. There was a positive relationship between egg load and female size. The mean of realized fecundity throughout the life span was 2.47 progenies per female. The mean developmental time of Q. mendeli from the egg to adult stage was 27.06 days. The shorter developmental time of Q. mendeli in comparison to its host can be considered a reason for the successful control of L. invasa in Thailand.


Assuntos
Himenópteros/fisiologia , Vespas/parasitologia , Animais , Agentes de Controle Biológico , Eucalyptus/parasitologia , Feminino , Fertilidade , Longevidade , Fenótipo , Tumores de Planta/parasitologia , Tailândia
8.
Sci Total Environ ; 662: 1012-1027, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30738602

RESUMO

The relationship between pesticides and pollinators, while attracting no shortage of attention from scientists, regulators, and the public, has proven resistant to scientific synthesis and fractious in matters of policy and public opinion. This is in part because the issue has been approached in a compartmentalized and intradisciplinary way, such that evaluations of organismal pesticide effects remain largely disjoint from their upstream drivers and downstream consequences. Here, we present a socioecological framework designed to synthesize the pesticide-pollinator system and inform future scholarship and action. Our framework consists of three interlocking domains-pesticide use, pesticide exposure, and pesticide effects-each consisting of causally linked patterns, processes, and states. We elaborate each of these domains and their linkages, reviewing relevant literature and providing empirical case studies. We then propose guidelines for future pesticide-pollinator scholarship and action agenda aimed at strengthening knowledge in neglected domains and integrating knowledge across domains to provide decision support for stakeholders and policymakers. Specifically, we emphasize (1) stakeholder engagement, (2) mechanistic study of pesticide exposure, (3) understanding the propagation of pesticide effects across levels of organization, and (4) full-cost accounting of the externalities of pesticide use and regulation. Addressing these items will require transdisciplinary collaborations within and beyond the scientific community, including the expertise of farmers, agrochemical developers, and policymakers in an extended peer community.


Assuntos
Borboletas/fisiologia , Dípteros/fisiologia , Himenópteros/fisiologia , Praguicidas , Polinização , Agricultura , Animais , Pesquisa
9.
Sci Rep ; 8(1): 17636, 2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-30518939

RESUMO

Phytophagous insects tend to be either cryptic and solitary, or brightly colored and gregarious, as a defense against vertebrate predators. Here, we tested whether potent defensive chemicals produced de novo by larvae of Argidae and Pergidae sawflies have influenced the evolutionary relationship between larval appearance and levels of gregariousness. Phylogeny-based correlation analyses indicated only a weak trend for solitary species to be cryptic, and for gregarious ones to be conspicuous. Numerous Argidae were cryptic-solitary or conspicuous-gregarious, whereas most Pergidae were conspicuous-gregarious. Both families also included not truly gregarious but aggregated species, i.e. with individuals more evenly distributed on the host plant. By considering two specific morphological traits, predominant body coloration and contrasting spots on body, each one was (weakly) associated with appearance but none with gregariousness, which reflects the functional relevance of appearance as a whole. Furthermore, Argidae can display alternate appearances during successive larval instars. Finally, an independent contrasts test showed no obvious correlation between two major toxic peptides. Our results point towards diversely combined patterns of linked ecological traits in these insects. By assuming that warning coloration is more warranted against vertebrate than invertebrate predators, we suggest that the occurrence itself of toxins allowed this diversity via differing predator guilds and environmental factors, to which these insects were confronted during evolution.


Assuntos
Evolução Biológica , Himenópteros/fisiologia , Peptídeos/metabolismo , Toxinas Biológicas/metabolismo , Animais , Herbivoria , Comportamento de Busca por Hospedeiro , Himenópteros/genética , Larva/genética , Larva/fisiologia , Peptídeos/genética , Filogenia , Plantas/parasitologia , Comportamento Predatório , Toxinas Biológicas/genética
10.
PLoS One ; 13(6): e0198803, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29894508

RESUMO

Understanding how climate change affects host-parasite systems and predicting the consequences for ecosystems, economies, and human health has emerged as an important task for science and society. Some basic insight into this complex problem can be gained by comparing the thermal physiology of interacting host and parasite species. In this study, we compared upper thermal tolerance among three component species in a natural host-parasitoid-hyperparasitoid system from Virginia, USA. To assess the ecological relevance of our results, we also examined a record of maximum daily air temperatures collected near the study site in the last 124 years. We found that the caterpillar host Manduca sexta had a critical thermal maximum (CTmax) about 4°C higher than the parasitic wasp, Cotesia congregata, and the hyperparasitic wasp, Conura sp., had a CTmax about 6°C higher than its host, C. congregata. We also found significant differences in CTmax among instars and between parasitized and non-parasitized M. sexta. The highest maximum daily air temperature recorded near the study in the last 124 years was 42°C, which equals the average CTmax of one species (C. congregata) but is several degrees lower than the average CTmax of the other two species (M. sexta, Conura sp.) in this study. Our results combined with other studies suggest that significant differences in thermal performance within and among interacting host and parasite species are common in nature and that climate change may be largely disruptive to these systems with responses that are highly variable and complex.


Assuntos
Adaptação Fisiológica , Interações Hospedeiro-Parasita , Himenópteros/classificação , Himenópteros/fisiologia , Manduca/fisiologia , Manduca/parasitologia , Termotolerância , Animais , Temperatura
11.
Toxicon ; 150: 74-76, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29705151

RESUMO

Arthropod venoms may be considered important sources of bioactive molecules; however, technical difficulties, such as venom extraction and homogeneity may impair the biochemical identification of new molecules. In this context, we have developed a method to maintain wasps in captivity that allows the collection of the venom, without use of chemical, mechanical or electrical stimuli. The crude venom was analyzed by RP-HPLC-ESIQ-ToF and 20 peptides were identified by de novo peptide sequencing, among them Eumenine-Mastoparan and a Ponericin-G2-simile peptide.


Assuntos
Himenópteros/fisiologia , Venenos de Vespas/química , Animais , Feminino , Peptídeos/química , Especificidade da Espécie , Venenos de Vespas/metabolismo
12.
Environ Entomol ; 47(3): 609-622, 2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29534165

RESUMO

A new gall midge, Asphondylia nepetae sp. n. Viggiani (Diptera: Cecidomyiidae), causing flower gall on Clinopodium nepeta (L.) Kuntze (Lamiaceae), is described from Europe. The morphological characteristics of adult, larvae, and pupa are described and illustrated. Molecular approach (by sequencing 28S-D2, ITS2, and COI) confirmed that A. nepetae is a distinct species. The development of the gall is always associated with the presence of the fungus Botryosphaeria dothidea (Moug.: Fr.) Ces. and De Not. (Botryosphaeriales: Botryosphaeriaceae). The new species can complete several generations per year, on the flowers of the same host plant and its adults emerge from late spring to autumn. Pupae overwinter inside peculiar flower galls in a state of quiescence. The impact of the pest is highly variable with a percentage of flowers infested that ranged between 3 and 57.5% in the sampled years. Insect mortality was, at least in part, due to parasitoids that attack the young stages of the midge. Among them, the dominant species was Sigmophora brevicornis (Panzer) (Chalcidoidea: Eulophidae).


Assuntos
Ascomicetos/fisiologia , Herbivoria , Lamiaceae/fisiologia , Nematóceros/classificação , Tumores de Planta , Animais , Complexo IV da Cadeia de Transporte de Elétrons/análise , Cadeia Alimentar , Himenópteros/fisiologia , Proteínas de Insetos/análise , Itália , Lamiaceae/microbiologia , Larva/classificação , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/fisiologia , Nematóceros/crescimento & desenvolvimento , Nematóceros/parasitologia , Nematóceros/fisiologia , Filogenia , Pupa/classificação , Pupa/crescimento & desenvolvimento , Pupa/parasitologia , Pupa/fisiologia
13.
Nat Prod Res ; 32(5): 514-520, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28503948

RESUMO

Utilisation of Anagrus nilaparvatae is a promising and effective method for planthoppers manipulation. Twenty-seven components of remote lemongrass (Cymbopogon distans) oil were identified by GC/MS and nine volatiles were selected for behavioural experiments. In this study, we noted that the remote lemongrass oil was attractive to female A. nilaparvatae at concentrations of 0.1 and 1 mg/L. α-Pinene, ß-pinene, eucalyptol, carveol and D-carvone attracted female wasps in the dose-dependent bioassays. Blend 1 (a mixture of eucalyptol, D-carvone, carveol, α-pinene, and ß-pinene with ratios of remote lemongrass oil volatiles of 625:80:11:5:3) attracted female wasps at 10 mg/L, while blend 2 (a mixture of the same five volatiles at the same loading ratio) attracted them at 0.1 and 1 mg/L. These results suggested that plant essential oils could be attractants for natural enemies to control pests. The ratios of volatiles in the mixtures affect the attractiveness of the synthetic mixtures.


Assuntos
Cymbopogon/química , Himenópteros/fisiologia , Óleos Voláteis/farmacologia , Vespas/efeitos dos fármacos , Vespas/fisiologia , Animais , Monoterpenos Bicíclicos , Agentes de Controle Biológico/farmacologia , Compostos Bicíclicos com Pontes/análise , Compostos Bicíclicos com Pontes/farmacologia , Monoterpenos Cicloexânicos , Cicloexanóis/análise , Cicloexanóis/farmacologia , Eucaliptol , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Monoterpenos/análise , Monoterpenos/farmacologia , Óleos Voláteis/química , Compostos Orgânicos Voláteis/análise
14.
Ann Agric Environ Med ; 24(3): 428-430, 2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28954484

RESUMO

INTRODUCTION: Numerous publications indicate that the prevalence of some infectious, neoplastic and immunological diseases are associated with ABO blood groups. OBJECTIVE: The aim of this study was to verify whether ABO and Rh blood groups are associated with severe anaphylactic reactions after Hymenoptera stings. MATERIAL AND METHODS: A study was undertaken of 71,441 Caucasian subjects living in the same geographic area. The study group included 353 patients with diagnosed systemic anaphylaxis to Hymenoptera venom. Control group included 71,088 healthy blood donors. Frequencies of ABO and Rhesus groups in the study and control groups were compared using univariate and multivariate analyses. RESULTS: No statistically significant interactions were observed between the ABO blood group and anaphylactic reactions to Hymenoptera.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Anafilaxia/imunologia , Himenópteros/fisiologia , Mordeduras e Picadas de Insetos/imunologia , Sistema do Grupo Sanguíneo Rh-Hr/imunologia , Sistema ABO de Grupos Sanguíneos/sangue , Adulto , Anafilaxia/sangue , Anafilaxia/etiologia , Animais , Venenos de Artrópodes/efeitos adversos , Venenos de Artrópodes/imunologia , Feminino , Humanos , Mordeduras e Picadas de Insetos/sangue , Masculino , Pessoa de Meia-Idade , Sistema do Grupo Sanguíneo Rh-Hr/sangue , População Branca
15.
Braz. j. biol ; 77(3): 566-568, July-Sept. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-888787

RESUMO

Abstract It is recorded for the first time in the state of Rio Grande do Sul the occurrence of Scobina melanocephala (Lepeletier, 1823), Scobina thoracica (Jorgensen, 1913) and Scobina poeciloides (Ashmead, 1895), being this last the first record for Brazil. Scobina melanopyga (Klug, 1834) and Scobina torquata (Konow, 1903) were also found in the study. The analyzed material was collected utilizing Malaise traps in tobacco (Nicotiana tabacum L.) fields and is deposited at the Entomological Collection of Santa Cruz do Sul.


Resumo É registrado pela primeira no estado do Rio Grande do Sul a ocorrência de Scobina melanocephala (Lepeletier, 1823), Scobina thoracica (Jorgensen, 1913) e Scobina poeciloides (Ashmead, 1895), esta última sendo registrada pela primeira vez no Brasil. Scobina melanopyga (Klug, 1834) e Scobina torquata (Konow, 1903) também foram encontradas no estudo. O material analisado foi coletado utilizando armadilhas de Malaise em cultivo de tabaco (Nicotiana tabacum L.) e estão depositados na Coleção Entomológica de Santa Cruz do Sul.


Assuntos
Animais , Masculino , Feminino , Distribuição Animal , Himenópteros/anatomia & histologia , Himenópteros/fisiologia , Brasil
16.
Plant Genome ; 10(1)2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28464069

RESUMO

Genetic diversity in breeding programs can be impaired by fixation of alleles derived from a limited number of founder lines. This is demonstrated with the use of a solid-stem trait derived from the Portuguese landrace 'S-615' over 70 yrs ago that is widely used to resist the wheat stem sawfly ( Norton, WSS) in North America. The objective of this study was to evaluate haplotype diversity underlying the quantitative trait locus (QTL) that controls the majority of the S-615 derived solid-stem genetic variation using single-nucleotide polymorphism (SNP) assays in a diverse set of 228 solid-stem tetraploid and hexaploid wheat accessions originating from areas of the world infested with various species of WSS. Haplotype analysis showed all WSS-resistant hexaploid wheat varieties in North America, except 'Conan', evaluated in this study contain a haplotype associated with the S-615 solid-stem allele. In total, 26 haplotypes were identified among the hexaploid and tetraploid accessions at . Prevalence of most haplotypes were skewed toward either the hexaploid or tetraploid wheat accessions. The haplotype found in the S-615- hexaploid wheat landrace was not found in the solid-stem tetraploid landrace accessions evaluated in this study. Haplotype analysis revealed several new haplotypes that have potential to contain novel alleles for solid-stems at , which may form the basis for introducing genetic diversity into breeding programs aimed at WSS resistance.


Assuntos
Resistência à Doença/genética , Variação Genética , Triticum/genética , Animais , Haplótipos , Himenópteros/fisiologia , Insetos/fisiologia , Fenótipo , Caules de Planta/parasitologia , Caules de Planta/fisiologia , Polimorfismo de Nucleotídeo Único , Poliploidia , Triticum/parasitologia
17.
Ecotoxicology ; 26(6): 782-791, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28439681

RESUMO

Telenomus podisi Ashmead (Hymenoptera: Platygastridae) is an important agent for the biological control of stink bug eggs in irrigated rice areas and the best strategy for its preservation is the use of selective pesticides. The aim of this study was to know the side-effects of pesticides used in Brazilian irrigated rice areas on egg parasitoid T. podisi. We evaluated, under laboratory conditions, 13 insecticides, 11 fungicides, 11 herbicides, and a control (distilled water) in choice and no-choice tests. In the no-choice tests, the pesticides were sprayed at pre and post-parasitism stages (egg and larval stages of T. podisi). In the choice tests, sprays were conducted only at pre-parasitism stages. For all tests, we prepared cards with 25 eggs of the alternative host Euschistus heros (Fabricius) (Hemiptera: Pentatomidae) non-parasitized (pre-parasitism) and parasitized (post-parasitism), which were subjected to pesticide sprays. The parasitism and emergence rates of T. podisi were determined classifying the pesticides in terms of the reduction of parasitism or emergence rates compared to the control. The neurotoxic insecticide cypermethrin, lambda-cyhalothrin, zeta-cypermethrin, etofenprox, thiamethoxam, thiamethoxam + lambda-cyhalothrin, acetamiprid + alpha-cypermethrin, and bifenthrin + alpha-cypermethrin + carbosulfan were more harmful to T. podisi and, therefore, are less suitable for the integrated management of insect pests in irrigated rice areas.


Assuntos
Himenópteros/fisiologia , Controle de Pragas/métodos , Praguicidas/toxicidade , Irrigação Agrícola , Animais , Brasil , Monitoramento Ambiental , Oryza , Medição de Risco
18.
Braz J Biol ; 77(3): 566-568, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27683815

RESUMO

It is recorded for the first time in the state of Rio Grande do Sul the occurrence of Scobina melanocephala (Lepeletier, 1823), Scobina thoracica (Jorgensen, 1913) and Scobina poeciloides (Ashmead, 1895), being this last the first record for Brazil. Scobina melanopyga (Klug, 1834) and Scobina torquata (Konow, 1903) were also found in the study. The analyzed material was collected utilizing Malaise traps in tobacco (Nicotiana tabacum L.) fields and is deposited at the Entomological Collection of Santa Cruz do Sul.


Assuntos
Distribuição Animal , Himenópteros/anatomia & histologia , Himenópteros/fisiologia , Animais , Brasil , Feminino , Masculino
19.
Parasite ; 23: 58, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28000590

RESUMO

Leptocybe invasa Fisher & La Salle (Hymenoptera, Eulophidae) is an invasive pest in Eucalyptus plantations throughout the world. Potential biological control agents for L. invasa were investigated in the Fujian, Guangdong, Hainan, Guangxi, Jiangxi, and Sichuan provinces of China, where Eucalyptus spp. have been severely damaged by the eucalyptus gall wasp. Three hymenopteran parasitoids of L. invasa were identified: Quadrastichus mendeli Kim & La Salle (Eulophidae), Aprostocetus causalis La Salle & Wu (Eulophidae), and Megastigmus viggianii Narendran & Sureshan (Torymidae); M. viggianii is newly recorded in China. The percentages of parasitization by Q. mendeli, A. causalis, and M. viggianii were 2.96%-19.53%, 2.30%-26.38%, and 24.93%, respectively. The longevity and body length of females were significantly greater than for males in A. causalis and M. viggianii. No males of Q. mendeli were found in China. These parasitoids could be used as biological agents for L. invasa in China.


Assuntos
Eucalyptus/parasitologia , Himenópteros/fisiologia , Controle Biológico de Vetores/métodos , Tumores de Planta/parasitologia , Vespas/parasitologia , Animais , China , Feminino , Himenópteros/anatomia & histologia , Himenópteros/classificação , Longevidade , Masculino , Tumores de Planta/economia , Vespas/patogenicidade
20.
Braz. j. biol ; 76(3): 774-781, tab, graf
Artigo em Inglês | LILACS | ID: lil-785026

RESUMO

Abstract Among the natural enemies of insect pests in rice fields, parasitoids are especially notable. To better understand the space-time dynamics of these insects, the objectives of this study were to describe and compare groups of parasitoids in organic irrigated rice fields using two management approaches for levee vegetation, and to relate them to the phenological stages of rice cultivation (the seedling, vegetative, and reproductive stages). The samples were taken in a plantation located in Viamão, RS, Brazil. The total area of 18 ha was divided into two parts: a no-cut (NC) subarea in which the wild vegetation of the levees was maintained, and a cut (C) subarea in which the levee vegetation was cut monthly. In each subarea, four Malaise traps considered as pseudo-replicas were installed and remained in the field for 24 hours at each sampling location. Collections occurred twice a month from the beginning of cultivation (October 2012) until harvest (March 2013). A total of 3,184 Hymenoptera parasitoids were collected: 2,038 individuals in the NC subarea and 1,146 in the C subarea. We identified 458 morphospecies distributed in 24 families. Mymaridae was the most abundant and Eulophidae was the richest in both subareas. A total of 198 morphospecies was shared between the subareas, including Platygastridae, Eulophidae, and Mymaridae, which were the families with the highest number of shared species. The richness and abundance of parasitoids varied according to their phenological developmental stages, with peak abundance registering during the vegetative period. The Morisita index identified three groupings, indicating a similarity that was related to the three phases of rice growth and development: seedling, vegetative and post-harvest.


Resumo Entre os inimigos naturais de insetos pragas em campos de arroz, parasitoides são especialmente notáveis. Para melhor entender a dinâmica espaço-temporal destes insetos, os objetivos desse estudo foram descrever e comparar os grupos de parasitoides em campos de arroz orgânico irrigado utilizando duas abordagens de manejo da vegetação das taipas, e relacioná-los com os estádios fenológicos da cultura (plântula, vegetativo e reprodutivo). As amostragens foram realizadas em uma plantação localizada em Viamão, RS. A área total de 18 ha foi dividida em duas partes: uma subárea não roçada (NR) na qual a vegetação espontânea das taipas foi mantida, e uma roçada (R) subárea em que a vegetação das taipas foi roçada mensalmente. Em cada subárea, quatro armadilhas Malaise consideradas pseudo-réplicas foram instaladas e mantiveram-se no campo durante 24 horas, em cada local de amostragem. As coletas ocorreram duas vezes por mês, desde o início do cultivo (outubro de 2012) até a colheita (março de 2013). Um total de 3.184 himenópteros parasitoides foram coletados: 2.038 indivíduos na subárea NR e 1.146 na R. Foram identificadas 458 morfoespécies, distribuídas em 24 famílias. Mymaridae foi a mais abundante e Eulophidae a mais rica para ambas as subáreas. Um total de 198 morfoespécies foi compartilhado entre as subáreas, incluindo Platygastridae, Eulophidae e Mymaridae, que foram as famílias com o maior número de espécies compartilhadas. A riqueza e a abundância de parasitoides variou de acordo com as fases de desenvolvimento fenológico da cultura, com pico de abundância registrado no período vegetativo. O Índice de Morisita identificou três grupamentos indicando uma similaridade relacionada às fases da cultura, plântula, vegetativo e, na pós-colheita.


Assuntos
Humanos , Animais , Oryza/crescimento & desenvolvimento , Oryza/parasitologia , Biodiversidade , Irrigação Agrícola , Himenópteros/fisiologia , Brasil , Dinâmica Populacional , Densidade Demográfica , Cadeia Alimentar , Biota
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