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1.
Braz. j. biol ; 83: e248154, 2023. tab, graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1339365

ABSTRACT

Abstract The cotton boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a key cotton crop pest in Brazil. Adverse climatic factors, such as high temperatures and low soil moisture, dehydrate oviposited cotton squares (bud flowers) on the ground and cause high mortality of its offspring within these plant structures. The objective of this research was to evaluate the mortality of the cotton boll weevil in drip and sprinkler irrigated cotton crops. The experimental design was in randomized blocks with two treatments: drip (T1) and sprinkler (T2, control) irrigated cotton crops with sixteen replications. Each parcel had one emergence cage, installed between two cotton rows per irrigation system, with 37 cotton squares with opened oviposition punctures and yellowish bracts, to capture adult cotton boll weevils. The average number of boll weevils that emerged from the cotton squares and the causes of mortality at different development stages were determined per treatment. Third-generation life tables of the boll weevil were prepared using the natural mortality data in drip and sprinkler irrigation treatments and plus actual, apparent and indispensable mortality rates and the lethality of each mortality cause. We conclude that the application of water directly to the root zone of the plants in a targeted manner, using the drip irrigation system, can cause high mortality of the cotton boll weevil immature stages inside cotton squares fallen on the ground. This is because the cotton squares fallen on the drier and hotter soil between the rows of drip-irrigated cotton dehydrates causing the boll weevils to die. This is important because it can reduce its population density of the pest and, consequently, the number of applications of chemical insecticides for its control. Thus, contributing to increase the viability of cotton production, mainly in areas of the Brazilian semiarid region where the cotton is cultivated in organic system.


Resumo O bicudo-do-algodoeiro, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), é uma praga-chave da cultura do algodão no Brasil. Fatores climáticos adversos, como altas temperaturas e baixa umidade do solo, desidratam os botões florais de algodão ovipositados caídos ao solo e causam alta mortalidade de seus descendentes dentro dessas estruturas vegetais.O objetivo desta pesquisa foi avaliar a mortalidade do bicudo-do-algodoeiro em lavouras de algodão irrigadas por gotejamento e aspersão. O delineamento experimental foi em blocos casualizados com dois tratamentos: cultivo de algodão irrigado por gotejamento (T1) e aspersão (T2, testemunha) com dezesseis repetições. Cada parcela possuía uma gaiola de emergência, instalada entre duas fileiras de algodão por sistema de irrigação, com 37 botões florais de algodão com orifícios de oviposição, brácteas abertas e amarelecidas, para captura do bicudo adulto. O número médio de bicudos que emergiu dos botões florais de algodão e as causas de mortalidade, em diferentes estágios de desenvolvimento, foram determinados por tratamento. As tabelas de vida de terceira geração do bicudo-do-algodoeiro foram preparadas usando os dados de mortalidade natural em tratamentos de irrigação por gotejamento e aspersão e as taxas de mortalidade reais, aparentes e indispensáveis e a letalidade de cada causa de mortalidade. Concluímos que a aplicação de água diretamente na zona radicular das plantas de forma direcionada, utilizando o sistema de irrigação por gotejamento, pode causar altas mortalidade dos estágios imaturos do bicudo-do-algodoeiro nos botões florais de algodão caídos no solo. Isso ocorre porque os botões florais de algodão caídos no solo mais seco e mais quente entre as fileiras do algodão irrigado por gotejamento desidratam, causando a morte dos bicudos. Isso é importante por poder reduzir a densidade populacional desse inseto e, consequentemente, o número de aplicações de inseticidas químicos para seu controle. Assim, contribuindo para aumentar a viabilidade da produção de algodão, principalmente em áreas do semiárido brasileiro em sistema orgânico.


Subject(s)
Animals , Coleoptera , Weevils , Insecticides , Oviposition , Crops, Agricultural
2.
Braz. j. biol ; 83: e247433, 2023. tab, graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1339336

ABSTRACT

Abstract The life cycle of stink bug, Glyphepomis dubia and the development of two egg parasitoids (Telenomus podisi and Trissolcus basalis) were studied at the Federal University of Maranhão, at 26 ± 2oC, relative humidity (RH) of 60 ± 10% and 12h photophase. Individuals used in the study were collected from seven rice fields located around the municipality of Arari, Maranhão, Brazil, and maintained in greenhouse and laboratory for the life cycle studies. From egg to adult, G. dubia took 35.2 days to complete the life cycle. The oviposition period was 37 days, with egg masses of about 12 eggs each and viability of 93.1%. Longevity was 53 and 65 days for females and males, respectively. The egg parasitoids Te. podisi and Tr. basalis parasitized and developed in G. dubia eggs; however, the biological characteristics of Tr. basalis were affected. Emergence of the parasitoids was higher for Te. podisi (83.5%) compared to the records for Tr. basalis (50.4%). Therefore, G. dubia may potentially achieve a pest status and Te. podisi is a promising biological control agent for G. dubia management in Brazil due to its higher longevity and better reproductive parameters.


Resumo O ciclo de vida do percevejo, Glyphepomis dubia e a biologia de dois parasitoides de ovos (Telenomus podisi e Trissolcus basalis) foram estudados na Universidade Federal do Maranhão, a 26 ± 2oC, umidade relativa (UR) de 60 ± 10% e fotofase de 12h. Sete indivíduos de G. dubia foram coletados em lavoura de arroz localizada no município de Arari, Maranhão, Brasil e mantidos em casa de vegetação e laboratório para estudos de ciclo de vida. Do ovo ao adulto, G. dubia levou 35.2 dias para completar o ciclo de vida. O período de oviposição foi de 37 dias com massas de ovos com cerca de 12 ovos/massa e viabilidade de 93.1%. A longevidade foi de 53 e 65 dias, respectivamente, para fêmeas e machos. Os parasitoides de ovos, Te. podisi e Tr. basalis parasitaram e se desenvolveram em ovos de G. dubia, no entanto as características biológicas de Tr. basalis foi afetada. A emergência dos parasitoides foi maior para Te. podisi (83.5%) em comparação com o registrado para Tr. basalis (50.4%). Portanto, G. dubia poderá apresentar potencial para atingir o status de praga e Te. podisi é um promissor agente de controle biológico para ser utilizado no manejo de G. dubia no Brasil, pois apresentou maior longevidade e os melhores parâmetros reprodutivos.


Subject(s)
Humans , Animals , Oryza , Wasps , Heteroptera , Hemiptera , Hymenoptera , Oviposition , Ovum , Biology
3.
Braz. j. biol ; 82: e255753, 2022. tab
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1355850

ABSTRACT

Abstract The leaf miner, Tuta absoluta is continue to be a serious threat to solanaceous plants, especially tomato plant worldwide. Tomato crop in Saudi Arabia has been recently affected by T. absoluta, which is difficult to control due to its unique biological features, such as high fecundity and its potential to develop resistance to chemical pesticides. In this article, the suitability and effectiveness of the predatory mite, Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae), an indigenous species usually found in tomato greenhouses of northcentral Saudi Arabia, has been evaluated on eggs and 1st instar larvae of T. absoluta in the laboratory. All experiments were conducted in an incubator at three constant temperatures of 22, 27 and 32°C ± 1°C, 50 ± 4% R.H. and L12:D12 h photoperiod. Adult females and males of N. cucumeris were able to feed and sustain oviposition on eggs and 1st instar larvae of T. absoluta, and could be an effective biocontrol agent against T. absoluta. The N. cucumeris had a clear preference for eggs compared to 1st instar larvae of T. absoluta. The results showed the obvious effect of the temperature on the consumption rate of the predatory mite. The maximum daily consumption rate occurred during the oviposition period, when the females of the predatory mite consumed an average of 4.26 eggs and 2.44 1st instar larvae of T. absoluta. In general, total fecundity was high with T. absoluta eggs as a food source when temperature increased from 22 to 32°C. The highest fecundity rate (42.92 and 20.97 eggs /female) was recorded at 32°C, while the lowest one (26.77 and 10.12 eggs / female) was recorded at 22°C, when N. cucumeris female fed on eggs and 1st instar larvae of T. absoluta, respectively. The results of this study indicated that the predatory mite, N. cucumeris can be considered a promising potential candidate for controlling the leaf miner T. absoluta, and further research is required to assess its effectiveness under greenhouse conditions.


Resumo A traça-do-tomateiro, Tuta absoluta, continua sendo uma séria ameaça às plantas solanáceas, especialmente ao tomateiro em todo o mundo. A safra de tomate na Arábia Saudita foi recentemente afetada por T. absoluta, o qual é de difícil controle por causa de suas características biológicas únicas, como alta fecundidade e potencial para desenvolver resistência a pesticidas químicos. Neste artigo, a adequação e a eficácia do ácaro predador Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae), uma espécie indígena geralmente encontrada em estufas de tomate no centro-norte da Arábia Saudita, foram avaliadas em ovos e larvas de 1º instar de T. absoluta em condições de laboratório. Todos os experimentos foram conduzidos em uma incubadora em três temperaturas constantes de 22, 27 e 32°C ± 1°C, 50 ± 4% UR e fotoperíodo L12: D12 h. Fêmeas e machos adultos de N. cucumeris foram capazes de se alimentar e sustentar a oviposição em ovos e larvas de 1º instar de T. absoluta, podendo ser um agente de biocontrole eficaz contra T. absoluta. Neoseiulus cucumeris teve uma clara preferência por ovos em comparação com larvas de 1º instar de T. absoluta. Os resultados mostram que mais presas foram consumidas conforme a temperatura aumentou de 22°C para 32°C. A taxa máxima de consumo diário ocorreu durante o período de oviposição, quando as fêmeas consumiram em média 4,26 ovos e 2,44 larvas de 1º instar de T. absoluta. Em geral, a fecundidade total foi maior com ovos de T. absoluta como fonte alimentar e com o aumento da temperatura. A maior taxa de fecundidade (42,92 e 20,97 ovos por fêmea) foi registrada a 32°C, enquanto a mais baixa (26,77 e 10,12 ovos por fêmea) foi a 22°C, quando N. cucumeris se alimentou de ovos e larvas de 1º instar de T. absoluta, respectivamente. Os resultados deste estudo indicam que o ácaro predador N. cucumeris pode ser considerado um potencial candidato para o controle da traça-do-tomateiro T. absoluta, e mais pesquisas são necessárias para avaliar sua eficácia em condições de estufa.


Subject(s)
Animals , Male , Female , Lycopersicon esculentum , Lepidoptera , Mites , Oviposition , Predatory Behavior , Pest Control, Biological , Larva
4.
Braz. j. biol ; 82: e233930, 2022. graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1278481
5.
Neotrop. ichthyol ; 19(1): e200079, 2021. mapas, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1154966

ABSTRACT

The function of the genital and anal papillae for insemination in Compsura heterura is discussed based on the description of their morphologies at different stages of the life cycle and during copulation and spawning. In males and females both the genital and anal papillae are involved in copulation in C. heterura. A pre-anal organ, anterior to the anus and stretched posteriorly, is present in adult males. The openings of the urinary channel and oviduct are separate in females. During copulation, there is an approximation between the female genital and anal papillae which become temporarily juxtaposed, forming a chamber enclosing the opening of the oviduct, which may also function in sperm capture. During spawning, the lateral edges of the female genital papilla are projected anteriorly, acquiring a tubular shape for oviposition.(AU)


A função das papilas genital e anal na inseminação em Compsura heterura é discutida com base na descrição de suas morfologias em diferentes estágios do ciclo de vida e por ocasião da cópula e desova. Em machos e fêmeas, as papilas genital e anal estão envolvidas na cópula. Um órgão pré-anal, anterior ao ânus e alongado posteriormente, está presente em machos adultos. Fêmeas possuem aberturas urinária e genital separadas. Durante a cópula, ocorre uma aproximação entre as papilas genital e anal femininas, que se justapõem temporariamente, formando uma câmara fechada onde se abre o oviduto, e que serve possivelmente à captura de esperma. Durante a desova, as bordas laterais da papila genital feminina são projetadas anteriormente, adquirindo um formato tubular para ovoposição.(AU)


Subject(s)
Animals , Characidae , Insemination , Life Cycle Stages , Oviposition
6.
Arq. Inst. Biol ; 88: e0752019, 2021. ilus, tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1348960

ABSTRACT

The two-spotted spider mite, Tetranychus urticae Koch, has caused significant damage to vineyards in the valley of the São Francisco River in Brazil. Neoseiulus idaeus Denmark & Muma is one of the most abundant species of predatory mites on vines in this region. This study evaluated the population growth rates of T. urticae on leaves of two grape (Vitis vinifera L.) cultivars ('Italia' and 'Superior Seedless') and jack bean [Canavalia ensiformis (L.) DC.] and, also, to estimate the predation rates of the pest mite by N. idaeus on leaves of both grape cultivars and jack bean. A higher oviposition rate of T. urticae was observed on 'Superior Seedless' than on 'Italia' grape leaves; however, there was no significant difference in the instantaneous growth rates of T. urticae for these grape cultivars. For 'Superior Seedless', the spider mite egg viability was significantly lower than on 'Italia' grape, indicating a resistance factor in this grape cultivar. The phytoseiid N. idaeus preyed higher number of T. urticae females on 'Superior Seedless' leaves than on 'Italia' grape and jack bean leaves for the densities of 10 and 20 pest mites per leaf arena (9 cm2). Evaluations of leaf trichomes in both grape cultivars indicated the occurrence of longer trichomes on the basal portion of the main veins of 'Superior Seedless' leaves. The presence of these longer trichomes may be associated with the better performance of N. idaeus on 'Superior Seedless' leaves.


Subject(s)
Tick Control , Vitis , Oviposition , Predatory Behavior , Pest Control, Biological , Mite Infestations
7.
Braz. j. biol ; 81(2): 326-334, 2021. graf, ilus
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1153361

ABSTRACT

This work aimed to describe the reproductive biology of Hypoptopoma inexspectatum in southern Pantanal. A total of 538 individuals were sampled and analyzed from February 2009 through January 2011 in southern Pantanal. We did not observe differences in sex-ratio, and both sexes presented positive allometric length/weight relationship (LWR). Reproduction occurs mainly from January to February. Females reached first maturation (L50) with 37.80 mm and males with 45.80 mm. Absolute fecundity is estimated in mean=177.43 (sd±127.06) oocytes and relative fecundity in 3.12 (sd±2.23) oocytes/mg. Fecundity is positively correlated with standard length (Spearman r= 0.43; p=0.013), and total spawning is a used spawning strategy for H. inexspectatum.


Este trabalho teve como objetivo descrever a biologia reprodutiva de Hypoptopoma inexspectatum na região do Pantanal Sul. Foram amostrados e analisados entre fevereiro de 2009 a janeiro de 2011 um total de 538 indivíduos. Não foi observada diferença na proporção sexual e ambos os sexos apresentam relação alométrica de peso/comprimento positiva. A reprodução ocorreu principalmente entre os meses de janeiro e fevereiro. Fêmeas atingiram o tamanho de primeira maturação (L50) com 37,80 mm e machos com 45,80 mm. A fecundidade absoluta média foi 177,43 (dp±127,06) ovócitos e a fecundidade relativa foi de 3,12 (dp±2,23) ovócitos/mg. A fecundidade foi positivamente correlacionada com o comprimento padrão (Spearman r= 0,43; p=0,013) e a desova parcelada foi a estratégia de desova utilizada por H. inexspectatum.


Subject(s)
Animals , Male , Female , Oviposition , Reproduction/physiology , Catfishes/physiology , Seasons , Brazil , Rivers
8.
Braz. j. biol ; 81(2): 448-451, 2021. tab, mapas
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1153353

ABSTRACT

This study was carried out in April - June 2014 to determine absolute fecundity (F) of the chub mackerel (Scomber japonicus Houttuyn, 1782) in Saros Bay (Aegean Sea, Turkey). The relations between the absolute fecundity and total length, total weight and age of the chub mackerel females were estimated as F=0.0318TL4.81, F=1573.9TW- 42858 and F=109607A-136129, respectively. This study aims to contribute to the reproductive biology of S. japonicus by reporting the first findings about the absolute fecundity of the species for the Aegean Sea.


Este estudo foi realizado em abril-junho de 2014 para determinar a fecundidade absoluta (F) da cavala (Scomber japonicus Houttuyn, 1782) na Baía de Saros (Mar Egeu, Turquia). As relações entre a fecundidade absoluta e comprimento total, peso total e a idade da cavala fêmeas foram estimados como F=0.0318TL4.81, F=1573.9 TW- 42858 e F=109607A-136129, respectivamente. Este estudo visa contribuir para a biologia reprodutiva de S. japonicus, apresentando as primeiras conclusões sobre a fecundidade absoluta das espécies para o Mar Egeu.


Subject(s)
Animals , Female , Body Weights and Measures/veterinary , Perciformes , Cyprinidae , Oviposition , Fertility
9.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1959-1964, Sept.-Oct. 2020. tab
Article in English | LILACS, VETINDEX | ID: biblio-1131525

ABSTRACT

This study aimed to estimate genetic parameters for simulated data of body weight (BW), abdominal width (AW), abdominal length (AL), and oviposition. Simulation was performed based on real data collected at apiaries in the region of Campo das Vertentes, Minas Gerais, Brazil. Genetic evaluations were performed using single- and two-trait models and (co)variance components were estimated by the restricted maximum likelihood method. The heritability for BW, AW, AL and oviposition were 0.54, 0.47, 0.31 and 0.66, respectively. Positive genetic correlations of high magnitude were obtained between BW and AW (0.80), BW and oviposition (0.69), AW and oviposition (0.82), and AL and oviposition (0.96). The genetic correlations between BW and AL (0.11) and between AW and AL (0.26) were considered moderate and low. In contrast, the phenotypic correlations were positive and high between BW and AW (0.97), BW and AL (0.96), and AW and AL (0.98). Phenotypic correlations of low magnitude and close to zero were obtained for oviposition with AL (0.02), AW (-0.02), and BW (-0.03). New studies involving these characteristics should be conducted on populations with biological data in order to evaluate the impact of selection on traits of economic interest.(AU)


Objetivou-se estimar parâmetros genéticos para dados simulados de peso corporal (PC), largura abdominal (LA), comprimento abdominal (CA) e oviposição (OV). A simulação foi conduzida com base em dados reais, coletados em apiários da região do Campo das Vertentes, Minas Gerais. As estimativas das análises genéticas foram realizadas por modelos uni e bicaracterísticos, sendo os componentes de (co) variância estimados pelo método da máxima verossimilhança restrita. As herdabilidades para PC, LA, CA e OV foram de 0,54, 0,47, 0,31 e 0,66 respectivamente. As correlações genéticas foram positivas e de alta magnitude para PC e LA (0,80), PC e OV (0,69), LA e OV (0,82) e CA e OV (0,96). Para PC e CA (0,11) e LA e CA (0,26), as correlações genéticas foram moderadas e de baixa magnitude. As correlações fenotípicas foram positivas e de alta magnitude para PC e LA (0,97), PC e CA (0,96) e LA e CA (0,98). Para OV e CA (0,02), OV e LA (-0,02) e OV e PC (-0,03), foram encontradas correlações fenotípicas de magnitude baixa e próximas de zero. Novos estudos devem ser realizados em populações com dados biológicos, a fim de se observar o impacto da seleção em características de interesse econômico.(AU)


Subject(s)
Animals , Oviposition/genetics , Bees/genetics , Body Weight/genetics , Body Weights and Measures/classification , Heredity , Correlation of Data
10.
Braz. j. biol ; 80(3): 641-647, July-Sept. 2020. tab, graf
Article in English | LILACS | ID: biblio-1132404

ABSTRACT

Abstract Among fruits and fruit products, oranges and orange juice are the most widely consumed worldwide. However, the effects of pest infestation of oranges on the quality of orange juice are not yet known. To evaluate the effect of the oriental fruit fly Bactrocera dorsalis on the antioxidant activity of orange juice, we measured changes in the vitamin C (Vc) concentration, total phenol content, and antioxidant activity of orange juice after the introduction of fruit fly eggs. Ten days after the eggs were introduced (larvae removed), the concentration of Vc in orange juice was 18.65 µg/mL, which was 9.16 µg/mL lower than that measured in healthy orange juice. In addition, the total phenol content decreased by 46.519 mg Gallic Acid Equivalents (GAE)/g to 9.748 mg GAE/g. Furthermore, the free-radical scavenging activity decreased from 22.297% to 5.393%. Correlation analysis indicated significant correlations between Vc concentration, total phenol content, and antioxidant activity of orange juice after B. dorsalis infestation. The decrease in Vc concentration, total phenol content and free-radical scavenging activity indicated that B. dorsalis changed the quality of orange juice by affecting the antioxidant activity of the juice after the oranges were infested.


Resumo Entre frutas e produtos de frutas, as laranjas e suco de laranja são os mais consumidos em todo o mundo. No entanto, os efeitos da infestação de laranjas sobre a qualidade do suco de laranja ainda não são conhecidos. Para avaliar o efeito da mosca-das-frutas oriental, Bactrocera dorsalis, sobre a atividade antioxidante do suco de laranja, foram medidas as mudanças na concentração de vitamina C (Vc), no teor de fenol total e na atividade antioxidante do suco de laranja após a introdução de ovos da mosca-das-frutas oriental. Dez dias após a introdução dos ovos (larvas removidas), a concentração de Vc no suco de laranja foi de 18,65 µg/mL, que foi 9,16 µg/mL menor do que a medida em suco de laranja saudável. Além disso, o teor total de fenol diminuiu de 46,519 mg em equivalente de ácido gípico (GAE)/g para 9,748 mg de GAE/g. Ademais, a atividade de eliminação de radicais livres diminuiu de 22,297% para 5,393%. A análise de correlação indicou correlações significativas dentre a concentração de Vc, o conteúdo total de fenol e a atividade antioxidante do suco de laranja após a infestação por B. dorsalis. A diminuição na concentração de Vc, o conteúdo total de fenol e a atividade sequestradora de radicais livres indicaram que B. dorsalis alterou a qualidade do suco de laranja, afetando a atividade antioxidante do suco após a infestação das laranjas.


Subject(s)
Animals , Female , Tephritidae , Citrus sinensis , Oviposition , Fruit , Antioxidants
11.
Acta amaz ; 50(3): 256-259, jul. - set. 2020.
Article in English | LILACS | ID: biblio-1118852

ABSTRACT

The oviposition behavior of the rare butterfly Minstrellus grandis (Callaghan, 1999) (Lepidoptera: Riodinidae) is recorded for the first time. Two females laid eggs on the old leaves of an unidentified Triplaris sp. (Polygonaceae), a myrmecophytic plant typically known as 'Triplaria' or 'novice' tree, inhabited by aggressive 'taxi' ants of the genus Pseudomyrmex sp. (Hymenoptera: Formicidae). These observations suggest that M. grandis caterpillars live associated with one of the most harmful types of Amazon ant-plant symbiosis. (AU)


Subject(s)
Ants , Symbiosis , Butterflies , Amazonian Ecosystem , Carnivory , Oviposition
12.
Ciênc. Saúde Colet ; 25(2): 665-672, Feb. 2020. tab, graf
Article in Portuguese | LILACS | ID: biblio-1055817

ABSTRACT

Resumo A dengue ocorre no Timor-Leste desde 2005, porém não existe um programa de monitoramento e controle do "Aedes aegypti". O objetivo deste estudo foi de avaliar a armadilha ovitrampa iscada com atraente natural como uma possível ferramenta para monitorar o vetor das arboviroses: Dengue (DENV), Chikungunya (CHIKV) e Zika (ZIKV). O estudo foi realizado na cidade de Dili, capital do Timor-Leste, entre as semanas epidemiológicas 32 (02/08) a 48 (02/12) de 2016. Foram instaladas 70 armadilhas Ovitrampa, em residências de 15 sucos (ruas), de quatro Postos Administrativos (bairros) da cidade. Para as analises dos dados utilizou-se os indicadores entomológicos: Índice de Positividade de Ovitrampa (IPO), Índice de Densidade Vetorial (IDV) e Índice de Densidade de Ovos (IDO). Durante o experimento foram coletados 158.904 ovos de Aedes spp.. O IPO demonstrou que todas as áreas tiveram 98% a 100% de armadilhas contendo ovos de Aedes spp.. Os indicadores IDO e IPO apresentaram correlações positivas e significativa com a temperatura. A defasagem de duas e três semanas para precipitação indicou correlação positiva significativa para IDV e IDO. Portanto, a armadilha ovitrampa é uma ferramenta que pode integrar as ações de um programa de monitoramento e controle de Aedes spp. no Timor-Leste.


Subject(s)
Humans , Animals , Female , Mosquito Control/methods , Aedes/virology , Mosquito Vectors/virology , Oviposition , Chikungunya virus/isolation & purification , Aedes/physiology , Dengue/prevention & control , Dengue/transmission , Dengue Virus/isolation & purification , Timor-Leste , Chikungunya Fever/prevention & control , Chikungunya Fever/transmission , Zika Virus/isolation & purification , Zika Virus Infection/prevention & control , Zika Virus Infection/transmission
13.
Rev. Soc. Bras. Med. Trop ; 53: e20200467, 2020. tab, graf
Article in English | ColecionaSUS, LILACS, ColecionaSUS, SES-SP | ID: biblio-1143874

ABSTRACT

Abstract INTRODUCTION: Semi-synthetic dillapiole compounds derived from Piper aduncum essential oil are used as alternative insecticides to control insecticide-resistant Aedes aegypti. Thus, we aimed to evaluate the genotoxic effects of semi-synthetic isodillapiole on the nuclei of neuroblasts (larvae) and oocytes (females) and the mean oviposition rates of the females over four generations (G1, G2, G3, and G4) of Ae. aegypti. METHODS: Larvae were captured in the city of Manaus, Amazonas state, Brazil, and exposed to isodillapiole in bioassays (20, 40, and 60 µg/mL) and a negative control (0.05% DMSO in tap water) for 4 h. The cerebral ganglia were extracted from the larvae and oocytes from the adult females to prepare slides for cytogenetic analysis. Breeding pairs were established and eggs counts were quantified taken after the bioassays. RESULTS: The analysis of 20,000 interphase nuclei of neuroblasts and oocytes indicated significant genotoxicity (micronuclei, budding, polynucleated cells, and other malformations) compared to that of the control. Metaphasic and anaphasic nuclei presented chromosomal breaks; however, no significant variation and damage was observed in the negative control. A significant reduction in mean oviposition rates was also recorded following exposure to isodillapiole over the four generations (G1, G2, G3, and G4). CONCLUSIONS: The toxic and genotoxic effects of isodillapiole on Ae. aegypti were caused by reduced oviposition in the females and nuclear abnormalities over the four generations of the trials. Further studies are required, rather than our in vitro assays, to verify the efficacy of exposure to this compound for controlling Ae. aegypti.


Subject(s)
Animals , Female , Aedes , Insecticides/toxicity , Oviposition , DNA Damage , Brazil , Larva
14.
Mem. Inst. Oswaldo Cruz ; 115: e200070, 2020. tab, graf
Article in English | SES-SP, LILACS, SES-SP | ID: biblio-1135278

ABSTRACT

BACKGROUND Nyssorhynchus deaneorum is a potential malaria vector because it has been shown to be competent to transmit Plasmodium vivax and Plasmodium falciparum, and because it exhibits antropophilic and endophilic behaviors in some regions of the Amazon. This profile makes Ny. deaneorum a useful mosquito for experiments that model Plasmodium-vector interactions in the Amazon. OBJECTIVE Herein we describe how a free-mating colony of Ny. deaneorum has been established using an automated light stimulation system. METHODS Mosquitoes were captured in São Francisco do Guaporé, Rondônia. The F1 generation was reared until adult emergence at which point copulation was induced using an automatic copulation induction system (ACIS). FINDINGS After four generations, natural mating and oviposition began to occur without light stimulation. The number of pupae and adult mosquitoes increased from the F5 to F10 generations. The new Ny. deaneorum colony exhibited susceptibility to P. vivax. MAIN CONCLUSIONS Automated light stimulation is an effective method for establishing an Ny. deaneorum colony under laboratory conditions as it produces enough adults to create a stenogamic colony. The establishment of a stable, P. vivax-susceptible colony of Ny. deaneorum makes it possible to model parasite-vector interactions and to test novel drug therapies that target parasite development in mosquitoes.


Subject(s)
Animals , Female , Oviposition , Copulation/physiology , Mosquito Vectors/parasitology , Insect Vectors/growth & development , Malaria , Anopheles/parasitology , Plasmodium falciparum , Plasmodium vivax , Brazil , Insect Vectors/physiology , Anopheles/physiology
15.
Mem. Inst. Oswaldo Cruz ; 115: e190437, 2020. tab, graf
Article in English | SES-SP, LILACS, SES-SP | ID: biblio-1135272

ABSTRACT

BACKGROUND Aedes aegypti and Aedes albopictus are the most important arbovirus vectors in the world. OBJECTIVES This study aimed to investigate and compare the infestation pattern of these species in a neighbourhood of Recife, Brazil, endemic for arboviruses in 2005 (T1) and 2013 (T2). METHODS Infestation, distribution and relative abundance of these sympatric species were recorded by egg collection using a network of 59 sentinel ovitraps (s-ovt) at fixed sampling stations for 12 months in T1 and T2. FINDINGS A permanent occupation pattern was detected which was characterised by the presence of egg-laying females of one or both species with a high ovitrap positivity index (94.3 to 100%) throughout both years analysed. In terms of abundance, the total of eggs collected was lower (p < 0.005) in T2 (146,153) than in T1 (281,103), although ovitraps still displayed a high index of positivity. The spatial distribution showed the presence of both species in 65.1% of the 148 s-ovt assessed, while a smaller number of traps exclusively contained Ae. aegypti (22%) or Ae. albopictus (13.2%) eggs. MAIN CONCLUSIONS Our comparative analysis demonstrated the robustness of the spatial occupation and permanence of Ae. aegypti and Ae. albopictus populations in this endemic urban area.


Subject(s)
Animals , Male , Female , Aedes/classification , Mosquito Vectors/classification , Oviposition , Arbovirus Infections/transmission , Arbovirus Infections/epidemiology , Seasons , Brazil/epidemiology , Population Density , Endemic Diseases , Aedes/physiology , Animal Distribution , Mosquito Vectors/physiology
16.
Mem. Inst. Oswaldo Cruz ; 115: e200046, 2020. tab, graf
Article in English | SES-SP, LILACS, SES-SP | ID: biblio-1135261

ABSTRACT

BACKGROUND Fluctuations in climate have been associated with variations in mosquito abundance. OBJECTIVES To analyse the influence of precipitation, temperature, solar radiation, wind speed and humidity on the oviposition dynamics of Aedes aegypti in three distinct environmental areas (Brasília Teimosa, Morro da Conceição/Alto José do Pinho and Dois Irmãos/Pintos) of the city of Recife and the Fernando de Noronha Archipelago northeastern Brazil. METHODS Time series study using a database of studies previously carried out in the areas. The eggs were collected using spatially distributed geo-referenced sentinel ovitraps (S-OVTs). Meteorological satellite data were obtained from the IRI climate data library. The association between meteorological variables and egg abundance was analysed using autoregressive models. FINDINGS Precipitation was positively associated with egg abundance in three of the four study areas with a lag of one month. Higher humidity (β = 45.7; 95% CI: 26.3 - 65.0) and lower wind speed (β = −125.2; 95% CI: −198.8 - −51.6) were associated with the average number of eggs in the hill area. MAIN CONCLUSIONS The effect of climate variables on oviposition varied according to local environmental conditions. Precipitation was a main predictor of egg abundance in the study settings.


Subject(s)
Animals , Female , Oviposition/physiology , Aedes/physiology , Population , Seasons , Brazil , Population Dynamics , Cities , Mosquito Vectors/physiology
17.
Arq. Inst. Biol ; 87: e1252018, 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1130107

ABSTRACT

The objective of this study was to evaluate the oviposition behavior of Helicoverpa armigera confined in different adult pair density and growth stages of soybean plants, and the resistance of soybean genotypes to H. armigera in the category nonpreference for oviposition. The oviposition behavior of H. armigera was assessed using one, two, and four adult pairs per soybean plant of the cultivar BR-16 at the growth stages: vegetative V8 (eighth unrolled trifoliate leaf), reproductive R2 (full bloom) and reproductive R5.2 (beginning seed). The nonpreference for oviposition was evaluated using eight soybean genotypes and an oviposition preference index was calculated. The number of trichomes in leaflets was quantified for being correlated to H. armigera oviposition. One adult pair and soybean plants stage at pod-set affected and showed the best results oviposition preference on soybean plants. The genotypes M8230-RR and W711-RR presented resistance characteristics, and PI-227687 was preferred for oviposition. The trichome density positively affects the female oviposition behavior.(AU)


O objetivo deste trabalho foi avaliar o comportamento de oviposição de Helicoverpa armigera confinadas em diferentes densidades de casais e estádios fenológicos de plantas de soja, e a resistência de genótipos de soja na categoria não preferência para oviposição para H. armigera. Para o comportamento de oviposição de H. armigera, foram avaliadas as densidades de um, dois e quatro casais por planta, e os estádios fenológicos vegetativo, de florescimento e reprodutivo de plantas de soja do cultivar BR 16. Para o teste de não preferência para oviposição, oito genótipos de soja foram utilizados e um índice de preferência para oviposição foi calculado. A densidade de tricomas nos folíolos foi quantificada para ser correlacionada com a oviposição de H. armigera. A densidade de um casal e plantas de soja em estádio reprodutivo proporcionaram os melhores resultados quanto à preferência para oviposição de H. armigera em soja. Os genótipos M8230 RR e W711 RR apresentaram características de resistência, enquanto o PI 227687 foi o mais preferido para oviposição. A quantidade de tricomas influenciou positivamente no comportamento de oviposição das fêmeas.(AU)


Subject(s)
Oviposition , Soybeans , Seeds , Trichomes , Genotype , Insecta , Lepidoptera
18.
Rev. patol. trop ; 49(1): 21-31, 2020. graf, tab
Article in English | LILACS | ID: biblio-1099703

ABSTRACT

Schistosomiasis is a parasitic disease caused by Schistosoma mansoni whose intermediate host is the snail of the genus Biomphalaria. This snail is geographically widespread, making the disease a serious public health problem. The purpose of this study was to analyze the growth, reproductive rates and mortality of B. glabrata and B. straminea in different calcium concentrations and food types. Freshly hatched snails stored in aquariums under different dietary and calcium supplementation programs were studied. Under these conditions, all planorbids survived, so there was no mortality rate and 79,839 eggs of B. straminea and 62,558 eggs of B. glabrata were obtained during the 2 months of oviposition. The following conditions: lettuce + fish food and lettuce + fish food + powdered milk resulted in the highest reproductive rates. In addition, supplementation with calcium carbonate and calcium sulfide in three different concentrations did not significantly influenced the amount of eggs or ovigerous masses. Thus, this study shows that changes in diet are crucial for the survival/oviposition of these planorbids, being an important study tool for population control. Calcium is also a key factor in these conditions, but more work is necessary to better assess its effect on snail survival.


Subject(s)
Oviposition , Schistosomiasis , Snails , Biomphalaria , Calcium , Food
19.
Braz. j. biol ; 79(3): 488-494, July-Sept. 2019. tab, graf
Article in English | LILACS | ID: biblio-1001450

ABSTRACT

Abstract In this study we evaluate the biotic potential and reproductive parameters of Spodoptera cosmioides (Walker, 1858) under controlled conditions (25 ± 1 °C, 70 ± 10% RH and 14 hour photophase). Females, on average, (14.433 days) did not live significantly longer than their male counterparts (13.100 days). The mean durations of the pre-oviposition, oviposition and post-oviposition periods were 2.767, 10.600 and 1.067 days, respectively. The mean fecundity of females was 5,073.533 eggs and the mean fertility was 5,021.027 larvae. On average, females copulated 1.167 times. Fecundity was positively correlated with the number of copulations (r = 0.583, P <0.001). The number of copulations, however, was negatively correlated whit the duration of the pre-oviposition (r = -0.560, P = 0.007) and oviposition (r = -0.479, P = 0.048) periods, and overall longevity (r = -0.512, P = 0.031). The biotic potential was estimated at 6.547 x 1021 individuals/female/year. The net reproductive rate (Ro) was 2,193.722 times per generation and the mean generation time (T) was 46.407 days. The intrinsic rate of increase (rm) was 0.166, with a finite rate of increase (λ) of 1.180, per week.


Resumo Neste estudo avaliamos o potencial biótico e parâmetros reprodutivos de Spodoptera cosmioides (Walker, 1858) em condições controladas (25 ± 1 °C, 70 ± 10% UR e 14 horas de fotofase). Em média, as fêmeas (14,433 dias) não viveram significativamente mais do que os machos (13,100 dias). A duração média dos períodos de pre-oviposição, oviposição e pós-oviposição foram 2,767; 10,600 e 1,067 dias, respectivamente. A fecundidade média das fêmeas foi de 5.073,533 ovos e a fertilidade média foi de 5.021,027 larvas. Em média, as fêmeas copularam 1,167 vezes. A fecundidade correlacionou-se positivamente com o número de cópulas (r = 0,583; P <0,001). Entretanto, o número de cópulas correlacionou-se negativamente com a duração dos períodos de pré-oviposição (r = -0,560; P = 0,007), oviposição (r = -0,479; P = 0;048) e a longevidade (r = -0,512; P = 0,031). O potencial biótico foi estimado em 6,547 x 1021 indivíduos/fêmea/ano. A taxa líquida de reprodução (Ro) foi de 2.193,722 vezes por geração e o tempo médio de cada geração (T) foi de 46,407 dias. A taxa intrínseca de crescimento (rm) foi 0,166, com uma taxa finita de aumento (λ) de 1,180, por semana.


Subject(s)
Animals , Male , Female , Oviposition , Sexual Behavior, Animal , Spodoptera/physiology , Life History Traits , Reproduction , Life Tables , Spodoptera/growth & development , Larva/growth & development , Larva/physiology , Longevity
20.
Rev. saúde pública (Online) ; 53: 29, jan. 2019. graf
Article in English | LILACS | ID: biblio-991645

ABSTRACT

ABSTRACT OBJECTIVE: To evaluate whether sites with large amount of potential breeding sites for immature forms of Aedes aegypti, called strategic points, influence in the active vector's dispersion into properties in their surroundings. METHODS: We selected four areas in the municipality of Campinas, three of them with strategic points classified as high, moderate, and low risk according to infestation and a control area, without strategic points. Between October 2015 and September 2016, we monthly installed oviposition traps and evaluated the infestation by Ae. aegypti in all properties of each selected area. To verify if there was vector dispersion from each strategic point, based on its location, we investigated the formation of clusters with excess of eggs or larvae or pupae containers, using the Gi spatial statistics. RESULTS: The amount of eggs collected in the ovitraps and the number of positive containers for Ae. aegypti did not show clusters of high values concerning its distance from the strategic point. Both presented random distribution not spatially associated with the positioning of strategic points in the area. CONCLUSIONS: Strategic points are not confirmed as responsible for the vector's dispersion for properties in their surroundings. We highlight the importance of reviewing the current strategy of the vector control program in Brazil, seeking a balance from the technical, operational, and economic point of view, without disregarding the role of strategic points as major producers of mosquitoes and their importance in the dissemination of arboviruses in periods of transmission.


RESUMO OBJETIVO: Avaliar se locais com grande quantidade de potenciais criadouros de formas imaturas de Aedes aegypti, denominados pontos estratégicos, influenciam a dispersão ativa do vetor aos imóveis no seu entorno. MÉTODOS: Foram selecionadas quatro áreas no município de Campinas, três delas com pontos estratégicos classificados como alto, médio e baixo risco segundo a infestação e uma área controle, sem ponto estratégico. Entre outubro de 2015 e setembro de 2016, instalaram-se mensalmente armadilhas de oviposição e avaliou-se a infestação por Ae. aegypti em todos os imóveis de cada área selecionada. Para verificar se houve dispersão do vetor a partir de cada ponto estratégico, com base em sua localização, investigou-se a formação de aglomerados com excesso de ovos ou de recipientes com larvas ou pupas, utilizando a estatística espacial Gi. RESULTADOS: o número de ovos coletados nas ovitrampas e o número de recipientes positivos para Ae. aegypti não apresentaram aglomerados de altos valores relativos à sua distância do ponto estratégico. Ambos apresentaram distribuição aleatória não associada espacialmente com o posicionamento dos pontos estratégicos na área. CONCLUSÕES: Pontos estratégicos não se confirmaram como responsáveis pela dispersão do vetor para os imóveis no seu entorno. Destaca-se a importância de rever a estratégia atual do programa de controle de vetores do Brasil, buscando um equilíbrio do ponto de vista técnico, operacional e econômico, sem desconsiderar o papel dos pontos estratégicos como grandes produtores de mosquitos e sua importância na disseminação de arboviroses em momentos de transmissão.


Subject(s)
Animals , Female , Oviposition/physiology , Pupa/growth & development , Mosquito Control/methods , Aedes/growth & development , Dengue/prevention & control , Mosquito Vectors/growth & development , Urban Population , Brazil , Environmental Monitoring , Mosquito Control/statistics & numerical data , Risk Factors , Aedes/virology , Dengue/transmission , Spatial Analysis , Animal Distribution/physiology , Mosquito Vectors/virology
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