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1.
Insects ; 15(9)2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39336693

RESUMO

This study investigates the species richness and distribution of ladybird beetles (Coccinellidae) across various habitats on San Cristóbal Island in the Galápagos Archipelago, Ecuador. Through extensive field surveys, we catalogued nineteen species, including four previously known species (two endemics, Psyllobora bisigma and Scymnobius scalesius, and two natives, Cycloneda sanguinea and Tenuisvalvae bromelicola). We also identified nine possibly native species reported for the first time in the Galapagos islands in this study or correspond to the first voucher specimens for the island. We collected three previously reported non-native species: Cheilomenes sexmaculata, Novius cardinalis, and Paraneda guticollis. Three species belonging to the genera Stethorus, Calloeneis, and Delphastus remain undetermined, pending further taxonomic analyses. Our findings reveal a rich and complex community with notable differences in species abundance and habitat preference. Endemic species were found to be particularly scarce and restricted mainly to crops undergoing forest regeneration and deciduous forests, emphasising their vulnerability and specialised habitat requirements. The native Cycloneda sanguinea emerged as the most prevalent species, exhibiting broad ecological adaptability. Non-native species, like Cheilomenes sexmaculata, were predominantly found in disturbed habitats, with some showing early signs of spreading into more natural environments, raising concerns about their potential impact on local biodiversity. These findings contribute valuable knowledge to understanding Coccinellidae diversity on San Cristóbal Island and highlight the importance of continued monitoring, particularly in the face of ongoing environmental change and the introduction of non-native species. This study underscores the need for targeted conservation efforts to protect the unique and fragile ecosystems of the Galápagos Archipelago.

2.
Arch Insect Biochem Physiol ; 116(3): e22125, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38973236

RESUMO

Insect pest control can be achieved by the application of RNA interference (RNAi), a key molecular tool in functional genomics. Whereas most RNAi research has focused on insect pests, few studies have been performed on natural enemies. Validating the efficacy of RNAi in natural enemies is crucial for assessing its safety and enabling molecular research on these organisms. Here, we assessed the efficacy of RNAi in the ladybird beetle Eriopis connexa Germar (Coleoptera: Coccinellidae), focusing on genes related to reproduction, such as vitellogenin (Vg) and its receptor (VgR). In the transcriptome of E. connexa, we found one VgR (EcVgR) and two Vg genes (EcVg1 and EcVg2). These genes have been validated by in silico analyses of functional domains and evolutionary relationships. Five-day-old females were injected with 500 ng/µL of a specific double-stranded RNA (dsRNA) (dsEcVg1, dsEcVg2, or dsEcVgR) for RNAi tests, while nonspecific dsRNA (dsGFP or dsAgCE8.1) was used as a control. Interestingly, dsEcVg2 was able to knockdown both Vg genes, while dsEcVg1 could silence only EcVg1. Additionally, the viability of the eggs was significantly reduced when both Vg genes were knocked down at the same time (after treatment with dsEcVg2 or "dsEcVg1+dsEcVg2"). Ultimately, malformed, nonviable eggs were produced when EcVgR was silenced. Interestingly, no dsRNA treatment had an impact on the quantity of eggs laid. Therefore, the feasibility of RNAi in E. connexa has been confirmed, suggesting that this coccinellid is an excellent Neotropical model for molecular research on natural enemies and for studying RNAi nontarget effects.


Assuntos
Besouros , Técnicas de Silenciamento de Genes , Interferência de RNA , Animais , Besouros/genética , Feminino , Vitelogeninas/genética , Vitelogeninas/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Reprodução/genética , RNA de Cadeia Dupla/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Proteínas do Ovo/genética , Proteínas do Ovo/metabolismo , Controle Biológico de Vetores
3.
Neotrop Entomol ; 52(2): 152-171, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36811712

RESUMO

The Amazon is an important source of natural enemies for biological control. The diversity of biocontrol agents in the Amazon is considerably higher than that in other Brazilian regions. However, few studies have focused on the bioprospecting of natural enemies in the Amazon. Furthermore, the expansion of agricultural land in recent decades has caused biodiversity loss in the region, including the loss of potential biocontrol agents, due to the replacement of native forests with cultivated areas and forest degradation. In this study, we reviewed the main groups of natural enemies in the Brazilian Legal Amazon: predatory mites (mainly Acari: Phytoseiidae), ladybirds (Coleoptera: Coccinellidae), and social wasps (Hymenoptera: Vespidae: Polistinae) and the Hymenoptera parasitoids of eggs (Trichogrammatidae) and of frugivorous larvae (Braconidae and Figitidae). The main species prospected and used in biological control are presented. The lack of knowledge and perspectives regarding these groups of natural enemies as well as the challenges of conducting research in the Amazon is discussed.


Assuntos
Besouros , Mariposas , Vespas , Animais , Larva , Biodiversidade , Controle Biológico de Vetores
4.
Rev. bras. entomol ; Rev. bras. entomol;67(2): e20220107, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1441261

RESUMO

ABSTRACT Chrysoperla externa (Hagen) and Hippodamia convergens (Guérin-Meneville) are voracious generalist predators, and important aphid control agents. In an environment containing a complex of species, the occurrence of intraguild interactions can interfere in the predator behavior and consumption. The aim of this work was to know the number of nymphs of Rhodobium porosum (Sanderson) and Macrosiphum rosae (Linnaeus) consumed by larvae of C. externa and H. convergens, and the interaction between these predators when confined together. First, second and third instar nymphs of R. porosum and M. rosae were provided in Petri dishes containing rose leaflets and second instar larvae of the predators. Intraguild interaction was studied in Petri dishes containing first instar nymphs of both aphid species and a second instar larva of C. externa plus one of H. convergens. A third treatment consisted of dishes containing a second instar larva of both predators maintained in the absence of prey. The evaluations took place throughout the entire instar of the predators. C. externa consumed a greater number of R. porosum nymphs and H. convergens a greater number of M. rosae nymphs. For both species of prey, the highest consumption was verified on the last day of evaluation. There was a positive interaction when the predator's larvae were confined in the presence of aphid nymphs, with no mortality observed for any of them. In the absence of prey, there was 70% mortality of H. convergens larvae due to intraguild predation.

5.
Braz. j. biol ; 82: e263276, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1384041

RESUMO

The Asian lady beetle Harmonia axyridis (Coleoptera: Coccinellidae) is a biological control agent that also may adversely impact other coccinellid species. Life table parameters were used to assess the population growth potential and the effects of interspecific competition between the invasive lady beetle H. axyridis and the native coccinellids Hippodamia convergens and Cycloneda sanguinea (Coleoptera: Coccinellidae) under laboratory conditions at 25 °C, using Schizaphis graminum (Hemiptera: Aphididae) as prey. The effects of the abiotic factors air temperature and humidity on these coccinellids by conducting a survey in a sorghum crop under average conditions of 18.1 °C and 53.5%, respectively, were also assessed. Fecundity was higher in C. sanguinea (1021.0 eggs per female) and H. axyridis (1029.2 eggs per female) than in H. convergens (484.5 eggs per female). The majority of the life table parameters showed no significant differences. The instantaneous rates of population increase (rm) of C. sanguinea, H. axyridis, and H. convergens were 0.195, 0.198, and 0.194 d-1, respectively. Based on the life table parameters obtained in this study, all three species of Coccinellidae showed a similar capacity to control a S. graminum population.


A joaninha asiática Harmonia axyridis (Coleoptera: Coccinellidae) é um agente de controle biológico que pode afetar negativamente outras espécies de coccinelídeos. Parâmetros da tabela de vida foram usados ​​para avaliar o potencial de crescimento populacional e os efeitos da competição interespecífica entre o coccinelídeo exótico H. axyridis e os coccinelídeos nativos Hippodamia convergens e Cycloneda sanguinea (Coleoptera: Coccinellidae) em condições de laboratório a 25 °C, usando Schizaphis graminum (Hemiptera: Aphididae) como presa. Também foram avaliados os efeitos dos fatores abióticos temperatura e umidade do ar sobre esses coccinelídeos por meio de levantamento em uma cultura de sorgo sob condições médias de 18,1 °C e 53,5%, respectivamente. A fecundidade foi maior em C. sanguinea (1021,0 ovos por fêmea) e H. axyridis (1029,2 ovos por fêmea) do que em H. convergens (484,5 ovos por fêmea). A maioria dos parâmetros da tabela de vida não apresentou diferenças significativas. As taxas intrínsicas de aumento (rm) de C. sanguinea, H. axyridis e H. convergens foram 0,195, 0,198 e 0,194 d­1, respectivamente. Com base nos parâmetros da tabela de vida obtidos neste estudo, as três espécies de Coccinellidae mostraram uma capacidade semelhante de controlar uma população de S. graminum.


Assuntos
Afídeos/crescimento & desenvolvimento , Besouros , Coccinella septempunctata
6.
Rev. peru. biol. (Impr.) ; 28(2): e18852, abr.-jun 2021. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1280521

RESUMO

Resumen Se presenta una revisión de los ejemplares de Coccinellini micofagos procedentes de varias provincias del departamento del Cusco, en el sur oriente de Perú. Este grupo presenta actualmente nueve especies en el país, dentro de los géneros Oxytella Weise 1902, y Psyllobora Chevrolat 1836. En el material examinado se reporta la ocurrencia de cinco de ellas: Oxytella longula Weise, Psyllobora marshalli Crotch, abancayana Almeida, P. constantini González, Perla & Almeida, y P. hybrida (Mulsant); además de otras tres especies, aún no identificadas, dentro del género Psyllobora. Para cada especie se presenta una diagnosis, fotografías y microfotografías de habito y estructuras genitales, e información sobre su distribución en Cusco.


Abstract In this work, we presented a review of the specimens of mycophagous Coccinellini from various provinces of the Cusco Department, south east of Peru. This group currently has nine species in the country, within the genera Oxytella Weise 1902, and Psyllobora Chevrolat 1836. In the material examined the occurrence of five of them is reported: Oxytella longula Weise, Psyllobora marshalli Crotch, P. abancayana Almeida, P. constantini González, Perla & Almeida, and P. hybrida (Mulsant); in addition to three other species, not yet identified, within the genus Psyllobora. For each species a diagnosis, photographs and photomicrographs of habit and genital structures, and information on their distribution in Cusco are presented.

7.
Biosci. j. (Online) ; 37: e37016, Jan.-Dec. 2021. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1358713

RESUMO

Plans for an agro-ecological system for agricultural production must consider vegetal diversification in agricultural properties because, among other advantages, it can help the biological control of pests when it focuses on such an end. Predator ladybeetles (Coleoptera: Coccinellidae) can be found in different environments; they play an important role in biological control. The aims of the present study were to feature ladybeetle populations through faunistic analysis and determine their fluctuations in an agro-ecological system comprising seven sub-systems subjected to different cultivation systems in Seropédica County, RJ. The experiment was conducted from December/2018 to December/2019 at Módulo de Cultivo Orgânico Intensivo de Hortaliças (MCOIH), which is located at Sistema Integrado de Produção Agroecológica (SIPA). In total, 1,231 adult ladybeetles were captured, distributed into 13 species, 3 genera and 2 tribes of Coccinellidae, which resulted in S (taxon richness) = 19, Shannon-Wiener diversity index (H') = 0.65 (at 0 to 1 scale) and Margalef diversity index (α) = 2.53 (values lower than 2.0 represent low diversity sites). Equitability was low (E = 0.22), since one of the ladybeetle species has prevailed: Cycloneda sanguinea (most frequent, dominating and constant) in MCOIH, as well as in each of the sub-systems. However, the simplest sub-systems installed for vegetable production (monoculture gardens) were not favorable for ladybeetle diversity, whereas sub-systems installed for polyculture of leafy vegetables recorded the greatest taxa diversity of ladybeetles, including species that predate in aphids that attack vegetables [Coleomegilla maculata, Coleomegilla quadrifasciata, Cycloneda sanguinea, Eriopis connexa, Harmonia axyridis, Hippodamia convergens and Hyperaspis (Hyperaspis) festiva]. The sub-system comprising gliricidia was used to produce fertilization biomass and favored the predominance of C. sanguinea in comparison to the other ladybeetle species in MCOIH. Spring was the season mostly favoring the occurrence of C. sanguinea and H. convergens adults; which were dominant species in ladybeetle assemblage in MCOIH; however, C. sanguinea was constant and H. convergens was accessory.


Assuntos
Besouros , Biodiversidade , Agricultura Sustentável , Controle Biológico de Vetores
8.
Rev. peru. biol. (Impr.) ; 27(2): 109-112, abr.-jun 2020. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1144939

RESUMO

Resumen Se cita por primera vez el género Neoparasitylenchus Nickle, 1967 (Tylenchida, Allantonematidae), parásito de Harmonia axyridis (Pallas, 1773) (Coleoptera, Coccinellidae) para Argentina. Se describe la especie nueva Neoparasitylenchus platense sp. n. que se caracteriza por tener en las formas de vida libre la región labial rodeada de una estructura plana, estilete delgado, levemente curvado, apéndice caudal redondeado, hembras con cuerpo marrón claro, estilete no hundido en el cuerpo y no prominente, vulva y ano subterminal, apéndice caudal redondeado, con una proyección en forma de clavija, ovíparos. Los machos con un estilete y un esófago parcialmente degenerados, espículas filiformes con base ensanchada, gubernaculum corto, bursa leptodera.


Abstract Presence of the genus Neoparasitylenchus Nickle, 1967 (Tylenchida, Allantonematidae), parasitizing Harmonia axyridis (Pallas, 1773) (Coleoptera, Coccinellidae) in Argentina. We describe a new species Neoparasitylenchus platense sp. n., which is characterized by having the free living stages lip region flatly rounded, spear slender, faintly knobbed, tail rounded, females with light brown body, stylet not sunken into body, and not prominent, subterminal vulva and anus, obtusely rounded tail end, with a peg-like projection, oviparous, and the males with a little stylet and partially degenerate oesophagus, spicules filiform with widened base, short gubernaculum, leptodera bursa.

9.
Neotrop Entomol ; 48(6): 909-918, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31321624

RESUMO

A successful pest control requires both chemical and biological agents for most commercially grown crops. However, insecticide resistance is increasing worldwide. Cabbage, a widely grown Brassicaceae, hosts the most resistant insect pest to insecticides, the diamondback moth (DBM), Plutella xylostella L. However, insecticide-resistant populations Eriopis connexa (Germar), a lady beetle often found controlling aphids and other soft-bodied pest species sharing brassica fields with DBM. Thus, as a model for integration of insecticide and biological control methods, we evaluated predation by pyrethroid-resistant and pyrethroid-susceptible lady beetles on DBM larvae offered alone and in the presence of a preferred prey, the aphid Lipaphis pseudobrassicae (Davis). During 24-h exposure, resistant and susceptible E. connexa consumed an average of 9.8 and 6.0 second-instar instar DBM larvae, respectively. Resistant beetles showed no significant preferences for prey consumption between untreated and deltamethrin-treated leaf surfaces, at field-recommended rate. As a function of DBM availability, resistant beetles exhibited similar predation on treated and untreated arena and higher predation than susceptible beetles in a treated arena. In greenhouse cages, resistant and susceptible beetles exhibited similar survival after 10 days on cabbage treated with deltamethrin and promoted the reduction of DBM to 5.0% and 5.6%, respectively. Both populations fed on a mixed diet of aphids and DBM larvae even under high availability of the preferred aphid prey. Resistant E. connexa survives deltamethrin exposure and do not alter their predatory behavior in response to this insecticide-treated environment.


Assuntos
Besouros/efeitos dos fármacos , Besouros/fisiologia , Inseticidas/farmacologia , Nitrilas/farmacologia , Comportamento Predatório , Piretrinas/farmacologia , Animais , Afídeos , Agentes de Controle Biológico , Brassica , Feminino , Resistência a Inseticidas , Larva , Mariposas
10.
Rev. peru. biol. (Impr.) ; 26(1): 27-32, ene.-mar. 2019. ilus
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1094349

RESUMO

Se cita y describe por primera vez para Argentina Parasitylenchus pseusobifurcatus sp.n. (Tylenchida, Allantonematidae), parásito de adultos de Harmonia axyridis (Pallas, 1773) (Coleopera, Coccinellidae). Esta nueva especie está muy cercana a P. bifurcatus Poinar Jr. y Steenberg, 2012, por la característica de tener todas las hembras vermiformes y los machos inmaduros la punta del apéndice caudal bifurcada, pero se diferencian entre otros por el tamaño del gubernáculo. Se describe su fórmula cariotípica.


Parasitylenchus pseusobifurcatus sp.n. (Tylenchida, Allantonematidae) is described for the first time for Argentina as a parasite of adults of Harmonia axyridis (Pallas, 1773) (Coleopera, Coccinellidae). The new species is closed to P. bifurcatus Poinar Jr. & Steenberg, 2012, by the characteristic of having the tail tip of all vermiform females and immature males bifurcated, but they differ by the size of the gubernaculum. Its karyotype formula is described.

11.
Ecotoxicol Environ Saf ; 147: 963-971, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29029382

RESUMO

Broad-spectrum insecticides may disrupt biological control and cause pest resurgence due to their negative impacts on natural enemies. The preservation of sustainable pest control in agroecosystems requires parallel assessments of insecticide toxicity to target pests and their key natural enemies. In the present study, the leaf dipping method was used to evaluate the relative toxicity of six insecticides to the striped mealybug, Ferrisia dasylirii (Cockerell) (Hemiptera: Pseudococcidae) and its predator, Tenuisvalvae notata (Mulsant) (Coleoptera: Coccinellidae). Three neurotoxic insecticides, lambda-cyhalothrin, methidathion and thiamethoxam, caused complete mortality of both pest and predator when applied at their highest field rates. In contrast, lufenuron, pymetrozine and pyriproxyfen caused moderate mortality of third-instar mealybug nymphs, and exhibited low or no toxicity to either larvae or adults of the lady beetle. At field rates, lufenuron and pymetrozine had negligible effects on prey consumption, development or reproduction of T. notata, but adults failed to emerge from pupae when fourth instar larvae were exposed to pyriproxyfen. In addition, pyriproxyfen caused temporary sterility; T. notata females laid non-viable eggs for three days after exposure, but recovered egg fertility thereafter. Our results indicate that the three neurotoxic insecticides can potentially control F. dasylirii, but are hazardous to its natural predator. In contrast, lufenuron and pymetrozine appear compatible with T. notata, although they appear less effective against the mealybug. Although the acute toxicity of pyriproxyfen to T. notata was low, some pupal mortality and reduced egg fertility suggest that this material could impede the predator's numerical response to mealybug populations.


Assuntos
Besouros/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Hemípteros/efeitos dos fármacos , Inseticidas/toxicidade , Controle Biológico de Vetores , Animais , Brasil , Besouros/crescimento & desenvolvimento , Feminino , Gossypium/parasitologia , Hemípteros/crescimento & desenvolvimento , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Ninfa/efeitos dos fármacos , Ninfa/crescimento & desenvolvimento , Comportamento Predatório/efeitos dos fármacos , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Reprodução/efeitos dos fármacos
12.
PeerJ ; 5: e3296, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28533958

RESUMO

The use of biological control agents to control pests is an alternative to pesticides and a tool to manage invasive alien species. However, biocontrol agents can themselves become invasive species under certain conditions. The harlequin ladybird (Harmonia axyridis) is a native Asian biocontrol agent that has become a successful invader. We reviewed articles containing "Harmonia axyridis" to gather information on its presence and surveyed entomologists researching Coccinellidae around the world to investigate further insights about the current distribution, vectors of introduction, habitat use and threats this species pose. The harlequin ladybird has established populations in at least 59 countries outside its native range. Twenty six percent of the surveyed scientists considered it a potential threat to native Coccinellidae. Published studies and scientists suggest Adalia bipunctata, native to Europe, is under the highest risk of population declines. Strict policies should be incorporated to prevent its arrival to non-invaded areas and to prevent further expansion range. Managing invasive species is a key priority to prevent biodiversity loss and promote ecosystem services.

13.
Zootaxa ; 4226(3): zootaxa.4226.3.7, 2017 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-28187625

RESUMO

Although Gordon (1975) revised the herbivorous ladybirds of the New World, the taxonomy of this group in the Americas is still poorly studied. Some recent efforts have been made at the generic (Szawaryn 2015b) as well as species level (Szawaryn 2015a; González & Gómez 2013; González 2015) to describe and improve our knowledge of the systematics of Neotropical Epilachnini, but they still need more investigation.


Assuntos
Besouros , Distribuição Animal , Animais , América do Sul
14.
Rev. peru. biol. (Impr.) ; 23(3): 325-328, Sept.-Dec. 2016. ilus
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1094277

RESUMO

For the first time in Argentina, we report that in Harmonia axyridis Pallas, 1773, and Cycloneda sanguinea (Linnaeus, 1763) (Coleoptera, Coccinellidae) parasitizing by nematodes which belong to the family of Allantonematidae (Nematoda, Tylenchida). The genera are Metaparasitylenchus Wachek, 1955 (Nickle, 1967), Sulphuretylenchus Rühm, 1956 (Nickle, 1967) and Contortylenchus Rühm, 1956. They will be described and photographied afterwards.


Se cita por primera vez para la Argentina nemátodos parásitos de Harmonia axyridis Pallas, 1773, y Cycloneda sanguinea (Linnaeus, 1763) (Coleoptera, Coccinellidae), estos nemátodos pertenecen a la familia de Allantonematidae (Nematoda, Tylenchida). Los géneros hallados son Metaparasitylenchus Wachek, 1955 (Nickle, 1967), Sulphuretylenchus Rühm, 1956 (Nickle, 1967) y Contortylenchus Rühm, 1956. Se describen y fotografían.

15.
Neotrop Entomol ; 45(5): 573-579, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27255766

RESUMO

The pyrethroid lambda-cyhalothrin is widely recommended for use against defoliators in crop ecosystems, but this broad-spectrum insecticide lacks efficacy against aphids; thus, key aphid predators such as the ladybird beetle Eriopis connexa (Germar) (Coleoptera: Coccinellidae) must be preserved. Given that populations of E. connexa recently identified as resistant to lambda-cyhalothrin show potential of integrating chemical and biological control in crop ecosystems, a historical goal of integrated pest management. In the present study, the resistance maintenance over F1, F2, and F3 progenies from crossing resistant (R) and susceptible (S) E. connexa populations that might be expected after releasing R predator in the crop field and the F1 offspring performance when the R population is crossed with the S population are evaluated. The offspring performance is determined for F1 progenies from crossing the R population at F40- and F45-reared generations in the laboratory with the S population at F38- and F1-reared generations in the laboratory. The mortality rate in the heterozygous F1 progeny is low and similar to the rate for the R population (<5%), but it is about 75% in F2 and F3 progenies from crossing R and S populations. Fecundity and longevity of the heterozygous F1 progeny are significantly greater compared to the R population. These results suggest that when R population beetles are released and mating with S population residents, their field offspring retains the resistance phenotype with the advantages of greater egg production and longer survival compared to the parental R population.


Assuntos
Besouros , Aptidão Genética , Resistência a Inseticidas , Inseticidas/farmacologia , Nitrilas/farmacologia , Piretrinas/farmacologia , Animais
16.
J Econ Entomol ; 108(1): 60-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26470104

RESUMO

Pyrethroid insecticides are widely recommended to control insect defoliators but lack efficacy against most aphid species. Thus, conserving aphid predators such as the lady beetle Eriopis connexa (Germar) is important to pest management in crop ecosystems that require pyrethroid sprays. In a greenhouse, early fourth-instar larvae and 5-day-old adults from susceptible (S) and resistant (R) E. connexa populations were caged on lambda-cyhalothrin-treated cotton plants, after which survival and egg production (for those caged at adult stage) were assessed. In the laboratory, similar groups were subjected to dried residues and topical treatment with one of eight pyrethroids (alpha-cypermethrin, bifenthrin, deltamethrin, esfenvalerate, fenpropathrin, permethrin, zeta-cypermethrin, and lambda-cyhalothrin), the organophosphate methidathion, or water and wetting agent. After caging on treated cotton terminals, 66% of the R-population larvae survived to adulthood, compared with 2% of those from the S-population. At 12 d after caging at adult stage under the same conditions, 64% of the females from the R-population survived and laid eggs, compared with 100% mortality and no oviposition for the S-females. In trials involving dried insecticide residues, gain in survival based on the survival difference (percentage for R-population minus percentage for S-population) across all tested pyrethroids varied from 3 to 63% for larvae and from 3 to 70% for adults. In trials involving topical sprays of the tested pyrethroids, survival differences ranged from 36 to 96% for larvae and from 21 to 82% for adults. Fenpropathrin and bifenthrin were the least and most toxic, respectively.


Assuntos
Besouros , Resistência a Inseticidas , Animais , Inseticidas , Larva , Nitrilas , Piretrinas
17.
Biol. Res ; 48: 1-14, 2015. graf, tab
Artigo em Inglês | LILACS | ID: biblio-950830

RESUMO

BACKGROUND: Changed temperature not only threaten agricultural production, but they also affect individual biological behavior, population and community of many insects, and consequently reduce the stability of our ecosystem. Insect's ability to respond to temperature stress evolved through a complex adaptive process, thus resulting in varied temperature tolerance among different insects. Both high and low extreme temperatures are detrimental to insect development since they constitute an important abiotic stress capable of inducing abnormal biological responses. Many studies on heat or cold tolerance of ladybirds have focused on measurements of physiological and biochemical indexes such as supercooling point, higher/lower lethal temperatures, survival rate, dry body weight, water content, and developmental duration. And studies of the molecular mechanisms of ladybird responses to heat or cold stress have focused on single genes, such as those encoding heat shock proteins, but has not been analyzed by transcriptome profiling. RESULTS: In this study, we report the use of Digital Gene Expression (DGE) tag profiling to gain insight into transcriptional events associated with heat- and cold-stress in C. montrouzieri. About 6 million tags (49 bp in length) were sequenced in a heat stress group, a cold stress group and a negative control group. We obtained 687 and 573 genes that showed significantly altered expression levels following heat and cold shock treatments, respectively. Analysis of the global gene expression pattern suggested that 42 enzyme-encoding genes mapped to many Gene Ontology terms are associated with insect's response to heat- and cold-stress. CONCLUSIONS: These results provide a global assessment of genes and molecular mechanisms involved in heat and cold tolerance.


Assuntos
Animais , Besouros/genética , Resposta ao Choque Térmico/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Resposta ao Choque Frio/genética , Transcriptoma , Estresse Fisiológico/genética , Besouros/classificação , Besouros/enzimologia , Biblioteca Gênica , Análise de Sequência de DNA/métodos , Genes de Insetos/fisiologia , Temperatura Baixa , Primers do DNA , Perfilação da Expressão Gênica/métodos , Reação em Cadeia da Polimerase em Tempo Real , Ontologia Genética , Temperatura Alta
18.
Neotrop Entomol ; 43(6): 555-63, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27194064

RESUMO

While searching for native natural enemies attacking invasive insect pests in Puerto Rico, we found four undescribed ladybug species belonging to the Caribbean ladybug genus Decadiomus Chapin. In this article, we describe the following species from Puerto Rico: Decadiomus seini n. sp., Decadiomus ramosi n. sp., Decadiomus hayuyai n. sp., and Decadiomus martorelli n. sp. Illustrations of the dorsal habitus, shape of prosternal carinae, and drawings of male and female genitalia are presented. We also present a key for Diomini of Puerto Rico and discuss their importance as potential biocontrol agents.


Assuntos
Besouros/classificação , Animais , Besouros/anatomia & histologia , Feminino , Genitália Feminina , Genitália Masculina , Masculino , Porto Rico
19.
Ecotoxicol Environ Saf ; 96: 53-60, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23856123

RESUMO

Simultaneous use of biological and chemical controls is a valued and historic goal of integrated pest management, but has rarely been achieved. One explanation for this failure may be the inadequate documentation of field populations of natural enemies for insecticide tolerance or resistance because natural enemies surviving insecticide application do not create problems like resistant pest species. Therefore, this study investigated 31 populations of lady beetles (Coleoptera: Coccinellidae) regarding their susceptibility to lambda-cyhalothrin, a pyrethroid insecticide that is widely used in cotton and other crops to control lepidopteran and coleopteran pests that are not targeted as prey by lady beetles. The study focused on seven coccinellid species common in cotton fields Coleomegilla maculata De Geer, Cycloneda sanguinea (L.), Eriopis connexa Germar, Harmonia axyridis (Pallas), Hippodamia convergens Guérin-Méneville, Olla v-nigrum (Mulsant), and Brumoides foudrasi (Mulsant) and one lady beetle species [Curinus coeruleus Mulsant] from a non-cotton ecosystem for comparisons. Dose-mortality curves were estimated after topical treatment of adult lady beetles with lambda-cyhalothrin. Statistically significant variations in lady beetle susceptibility were observed between species and between populations of a given species. Seven and eighteen populations of lady beetles exhibited greater values of LD50 and LD90, respectively, than the highest recommended field rate of lambda-cyhalothrin (20g a.i./hectare≈0.2g a.i./L) for cotton fields in Brazil. Furthermore, based on LD50 values, 29 out of 30 tested populations of lady beetles exhibited ratios of relative tolerance varying from 2- to 215-fold compared to the toxicity of lambda-cyhalothrin to the boll weevil, Anthonomus grandis Boh. (Coleoptera: Curculionidae). Four populations of E. connexa were 10.5-37.7 times more tolerant than the most susceptible population and thus were considered to be resistant to lambda-cyhalothrin, the first record of resistance for this species. These findings demonstrate that field selection for resistance to lambda-cyhalothrin in common lady beetles is occurring, opening up possibilities to effectively integrate biological control where the popular insecticide lambda-cyhalothrin is used.


Assuntos
Besouros/efeitos dos fármacos , Resistência a Medicamentos/fisiologia , Inseticidas/toxicidade , Nitrilas/toxicidade , Piretrinas/toxicidade , Animais , Agentes de Controle Biológico , Brasil , Dose Letal Mediana
20.
Arq. Inst. Biol. (Online) ; 78(4): 537-544, out.-dez. 2011. tab
Artigo em Português | VETINDEX | ID: biblio-1414608

RESUMO

Identificar pesticidas seletivos a inimigos naturais é fundamental para a boa prática do Manejo Integrado de Pragas. Este estudo objetivou avaliar a seletividade dos seguintes agroquímicos (em g i.a. L-1 de água) sobre o predador Cycloneda sanguinea (Linnaeus, 1763) (Coleoptera: Coccinellidae): triflumurom (Certero 480 SC ­ 0,048), espinosade (Tracer 480 SC ­ 0,24), clorfenapir (Pirate 240 SC ­ 1,2), clotianidina (Focus 500 PM ­ 0,33), imidaclopride+ß-ciflutrina (Connect 100/12,5 SC ­ 0,33/0,042), e água destilada como tratamento testemunha. As pulverizações dos produtos foram realizadas em pupas e adultos de C. sanguinea por meio de torre de Potter; as pupas permaneceram individualizadas até a emergência dos adultos quando foram formados casais. Para os adultos tratados, os casais foram formados logo após as aplicações dos produtos. Os bioensaios foram conduzidos a 25 ± 2º C, UR 60 ± 10% e fotofase de 12h. Avaliou-se a duração, sobrevivência e razão sexual de pupas diretamente tratadas; sobrevivência e parâmetros reprodutivos de adultos diretamente tratados; sobrevivência e duração dos estádios de desenvolvimento larval e pupal, razão sexual e parâmetros reprodutivos de adultos provenientes de pupas e adultos diretamente tratados. Os inseticidas triflumuron e espinosade foram seletivos às pupas de C. sanguinea, levemente nocivos aos adultos do predador, assim como às suas fases e gerações subsequentes de desenvolvimento. Clorfenapir, clotianidina e imidaclopride+ß-ciflutrina foram tóxicos a pupas e adultos de C. sanguinea.


Identifying pesticides that are selective in regard to natural enemies is critical to good practice of integrated pest management. This study was aimed to evaluate the selectivity of the following pesticides (in g a.i. L-1 of water) in regard to the predator Cycloneda sanguinea (Linnaeus, 1763) (Coleoptera: Coccinellidae): triflumuron (Certero SC 480 ­ 0.048), spinosad (Tracer 480 SC ­ 0.24), chlorfenapyr (Pirate SC 240 ­ 1.2), clothianidin (Focus 500 PM ­ 0.33), beta-cyfluthrin + imidacloprid (Connect 100/12, SC 5 ­ 0.33 / 0.042), and distilled water as a control treatment. The products were sprayed on C. sanguinea pupae and adults using a Potter's tower; the pupas were kept singly until they became adults, when couples were made. For adults, the couples were made after the application of the products. The bioassays were realized at 25 ± 2º C, RU 60 ± 10% and photophase of 12h. Evaluations were made of the duration, survival and sexual rate of directly treated pupae; survival and reproductive parameters of directly treated adults; survival and duration of the larval and pupal development stages, sexual ratio and reproductive parameters of adults developed from pupae and of directly treated adults. Triflumuron and spinosad were innocuous to the C. sanguinea pupae, and slightly prejudicial to the adults of the predator as well to its phases and generations following development. Chlorfenapyr, chlothianidin and imidacloprid/ß-cyfluthrin were toxic to C. sanguinea pupae and adults.


Assuntos
Besouros/efeitos dos fármacos , Gossypium/efeitos dos fármacos , Inseticidas
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