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1.
Braz. j. biol ; 83: 1-6, 2023. tab
Article in English | LILACS, VETINDEX | ID: biblio-1468955

ABSTRACT

The possible interference of resistant pest’s populations to insecticides in natural enemies in the action thas not been clarified yet. Thus, this study aimed to evaluate Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) performance on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) eggs with resistance frequency to the Metaflumizone over six generations of product exposure. Egg cards (2.0 x 7.0 cm) containing eggs from two populations of S. frugiperda, (resistant to Metaflumizone and the other susceptible), were exposed to T. pretiosum females for 24 hours in free-choice and no-choice testing in three generations (G1, G4, and G6). A completely randomized experimental design was used with 25 replications, each consisting of an egg card (experimental unit) containing 20 eggs. The parameters evaluated were: parasitism (%), emergence (%), sex ratio, number of emerged parasitoids per egg and males/females longevity. ANOVA and Tukey test (P≤ 0.05) were applied on the results. Results showed a reduction in parasitism [41.0% (G1) and 28.4% (G4)], egg emergence (17.5%) and parasitoids/egg [16.2 (G4) and 17.2 (G6)] in eggs originating from the population with resistance frequency. Females emerging from G6 populations eggs without exposure to Metaflumizone had greater longevity (3.5 days more) than the resistant population. The sex ratio and male longevity were not affected. The results indicate a reduction in T. pretiosum activity if S. frugiperda populations have some frequency of resistance to Metaflumizone.


A possível interferência de populações de pragas resistentes na ação de inimigos naturais ainda não foi esclarecida. Assim, este trabalho teve como objetivo avaliar o desempenho de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) em ovos de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) com frequência de resistência à Metaflumizona ao longo de seis gerações de exposição ao produto. Cartelas (2,0 x 7,0 cm) com ovos de duas populações de S. frugiperda, (resistente à Metaflumizona e outra suscetível), foram expostas às fêmeas de T. pretiosum por 24 horas em condições de livre escolha e sem chance de escolha por três gerações (G1, G4 e G6). O delineamento experimental foi inteiramente casualizado com 25 repetições, sendo cada repetição composta por uma cartela (unidade experimental) contendo 20 ovos. Os parâmetros avaliados foram: parasitismo (%), emergência (%), razão sexual, número de parasitoides emergidos por ovo e longevidade de machos e fêmeas. ANOVA e teste de Tukey (P≤ 0,05) foram aplicados aos dados coletados. Os resultados mostraram redução do parasitismo [41,0% (G1) e 28,4% (G4)], emergência de ovos (17,5%) e parasitoides/ovo [16,2 (G4) e 17,2 (G6)] em ovos oriundos da população com frequência de resistência. As fêmeas emergidas de ovos da população G6 sem exposição à Metaflumizona, tiveram maior longevidade (3,5 dias a mais) do que a população exposta ao inseticida. A razão sexual e a longevidade de machos não foram afetadas. Os resultados indicam uma redução na atividade de T. pretiosum se as populações de S. frugiperda apresentarem alguma frequência de resistência à Metaflumizona.


Subject(s)
Animals , Hymenoptera/drug effects , Insecticides/administration & dosage , Spodoptera/parasitology
2.
Braz. j. biol ; 832023.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469171

ABSTRACT

Abstract The possible interference of resistant pests populations to insecticides in natural enemies in the action thas not been clarified yet. Thus, this study aimed to evaluate Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) performance on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) eggs with resistance frequency to the Metaflumizone over six generations of product exposure. Egg cards (2.0 x 7.0 cm) containing eggs from two populations of S. frugiperda, (resistant to Metaflumizone and the other susceptible), were exposed to T. pretiosum females for 24 hours in free-choice and no-choice testing in three generations (G1, G4, and G6). A completely randomized experimental design was used with 25 replications, each consisting of an egg card (experimental unit) containing 20 eggs. The parameters evaluated were: parasitism (%), emergence (%), sex ratio, number of emerged parasitoids per egg and males/females longevity. ANOVA and Tukey test (P 0.05) were applied on the results. Results showed a reduction in parasitism [41.0% (G1) and 28.4% (G4)], egg emergence (17.5%) and parasitoids/egg [16.2 (G4) and 17.2 (G6)] in eggs originating from the population with resistance frequency. Females emerging from G6 populations eggs without exposure to Metaflumizone had greater longevity (3.5 days more) than the resistant population. The sex ratio and male longevity were not affected. The results indicate a reduction in T. pretiosum activity if S. frugiperda populations have some frequency of resistance to Metaflumizone.


Resumo A possível interferência de populações de pragas resistentes na ação de inimigos naturais ainda não foi esclarecida. Assim, este trabalho teve como objetivo avaliar o desempenho de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) em ovos de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) com frequência de resistência à Metaflumizona ao longo de seis gerações de exposição ao produto. Cartelas (2,0 x 7,0 cm) com ovos de duas populações de S. frugiperda, (resistente à Metaflumizona e outra suscetível), foram expostas às fêmeas de T. pretiosum por 24 horas em condições de livre escolha e sem chance de escolha por três gerações (G1, G4 e G6). O delineamento experimental foi inteiramente casualizado com 25 repetições, sendo cada repetição composta por uma cartela (unidade experimental) contendo 20 ovos. Os parâmetros avaliados foram: parasitismo (%), emergência (%), razão sexual, número de parasitoides emergidos por ovo e longevidade de machos e fêmeas. ANOVA e teste de Tukey (P 0,05) foram aplicados aos dados coletados. Os resultados mostraram redução do parasitismo [41,0% (G1) e 28,4% (G4)], emergência de ovos (17,5%) e parasitoides/ovo [16,2 (G4) e 17,2 (G6)] em ovos oriundos da população com frequência de resistência. As fêmeas emergidas de ovos da população G6 sem exposição à Metaflumizona, tiveram maior longevidade (3,5 dias a mais) do que a população exposta ao inseticida. A razão sexual e a longevidade de machos não foram afetadas. Os resultados indicam uma redução na atividade de T. pretiosum se as populações de S. frugiperda apresentarem alguma frequência de resistência à Metaflumizona.

3.
Braz. j. biol ; 83: e245273, 2023. tab
Article in English | LILACS, VETINDEX | ID: biblio-1339412

ABSTRACT

Abstract The possible interference of resistant pest's populations to insecticides in natural enemies in the action thas not been clarified yet. Thus, this study aimed to evaluate Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) performance on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) eggs with resistance frequency to the Metaflumizone over six generations of product exposure. Egg cards (2.0 x 7.0 cm) containing eggs from two populations of S. frugiperda, (resistant to Metaflumizone and the other susceptible), were exposed to T. pretiosum females for 24 hours in free-choice and no-choice testing in three generations (G1, G4, and G6). A completely randomized experimental design was used with 25 replications, each consisting of an egg card (experimental unit) containing 20 eggs. The parameters evaluated were: parasitism (%), emergence (%), sex ratio, number of emerged parasitoids per egg and males/females longevity. ANOVA and Tukey test (P≤ 0.05) were applied on the results. Results showed a reduction in parasitism [41.0% (G1) and 28.4% (G4)], egg emergence (17.5%) and parasitoids/egg [16.2 (G4) and 17.2 (G6)] in eggs originating from the population with resistance frequency. Females emerging from G6 populations eggs without exposure to Metaflumizone had greater longevity (3.5 days more) than the resistant population. The sex ratio and male longevity were not affected. The results indicate a reduction in T. pretiosum activity if S. frugiperda populations have some frequency of resistance to Metaflumizone.


Resumo A possível interferência de populações de pragas resistentes na ação de inimigos naturais ainda não foi esclarecida. Assim, este trabalho teve como objetivo avaliar o desempenho de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) em ovos de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) com frequência de resistência à Metaflumizona ao longo de seis gerações de exposição ao produto. Cartelas (2,0 x 7,0 cm) com ovos de duas populações de S. frugiperda, (resistente à Metaflumizona e outra suscetível), foram expostas às fêmeas de T. pretiosum por 24 horas em condições de livre escolha e sem chance de escolha por três gerações (G1, G4 e G6). O delineamento experimental foi inteiramente casualizado com 25 repetições, sendo cada repetição composta por uma cartela (unidade experimental) contendo 20 ovos. Os parâmetros avaliados foram: parasitismo (%), emergência (%), razão sexual, número de parasitoides emergidos por ovo e longevidade de machos e fêmeas. ANOVA e teste de Tukey (P≤ 0,05) foram aplicados aos dados coletados. Os resultados mostraram redução do parasitismo [41,0% (G1) e 28,4% (G4)], emergência de ovos (17,5%) e parasitoides/ovo [16,2 (G4) e 17,2 (G6)] em ovos oriundos da população com frequência de resistência. As fêmeas emergidas de ovos da população G6 sem exposição à Metaflumizona, tiveram maior longevidade (3,5 dias a mais) do que a população exposta ao inseticida. A razão sexual e a longevidade de machos não foram afetadas. Os resultados indicam uma redução na atividade de T. pretiosum se as populações de S. frugiperda apresentarem alguma frequência de resistência à Metaflumizona.


Subject(s)
Animals , Male , Female , Wasps , Hymenoptera , Moths , Semicarbazones , Sex Ratio , Spodoptera
4.
Eur J Clin Nutr ; 76(12): 1705-1712, 2022 12.
Article in English | MEDLINE | ID: mdl-35906333

ABSTRACT

Intrauterine environment can influence the offspring's body adiposity whose distribution affect the cardiometabolic risk. Underlying mechanisms may involve the gut microbiome. We investigated associations of gestational weight gain with the adult offspring's gut microbiota, body adiposity and related parameters in participants of the Nutritionists' Health Study. METHODS: This cross-sectional analysis included 114 women who had early life and clinical data, body composition, and biological samples collected. The structure of fecal microbiota was analyzed targeting the V4 region of the 16 S rRNA gene. Beta diversity was calculated by PCoA and PERMANOVA used to test the impact of categorical variables into the diversity. Bacterial clusters were identified based on the Jensen-Shannon divergence matrix and Calinski-Harabasz index. Correlations were tested by Spearman coefficient. RESULTS: Median age was 28 (IQR 24-31) years and BMI 24.5 (IQR 21.4-28.0) kg/m2. Fifty-eight participants were assigned to a profile driven by Prevotella and 56 to another driven by Blautia. Visceral adipose tissue was correlated to abundance of Acidaminococcus genus considering the entire sample (r = 0.37; p < 0.001) and the profiles (Blautia: r = 0.35, p = 0.009, and Prevotella: r = 0.38, p = 0.006). In Blautia-driven profile, the same genus was also correlated to maternal gestational weight gain (r = 0.38, p = 0.006). CONCLUSIONS: Association of Acidaminococcus with gestational weight gain could reinforce the relevance with mothers' nutritional status for gut colonization at the beginning of life. Whether Acidaminococcus abundance could be a marker for central distribution of adiposity in young women requires further investigation.


Subject(s)
Gestational Weight Gain , Adult , Humans , Female , Adiposity , Acidaminococcus , Body Mass Index , Cross-Sectional Studies , Adult Children , Obesity, Abdominal , Obesity
5.
Braz J Biol ; 83: e245273, 2021.
Article in English | MEDLINE | ID: mdl-34669790

ABSTRACT

The possible interference of resistant pest's populations to insecticides in natural enemies in the action thas not been clarified yet. Thus, this study aimed to evaluate Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) performance on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) eggs with resistance frequency to the Metaflumizone over six generations of product exposure. Egg cards (2.0 x 7.0 cm) containing eggs from two populations of S. frugiperda, (resistant to Metaflumizone and the other susceptible), were exposed to T. pretiosum females for 24 hours in free-choice and no-choice testing in three generations (G1, G4, and G6). A completely randomized experimental design was used with 25 replications, each consisting of an egg card (experimental unit) containing 20 eggs. The parameters evaluated were: parasitism (%), emergence (%), sex ratio, number of emerged parasitoids per egg and males/females longevity. ANOVA and Tukey test (P≤ 0.05) were applied on the results. Results showed a reduction in parasitism [41.0% (G1) and 28.4% (G4)], egg emergence (17.5%) and parasitoids/egg [16.2 (G4) and 17.2 (G6)] in eggs originating from the population with resistance frequency. Females emerging from G6 populations eggs without exposure to Metaflumizone had greater longevity (3.5 days more) than the resistant population. The sex ratio and male longevity were not affected. The results indicate a reduction in T. pretiosum activity if S. frugiperda populations have some frequency of resistance to Metaflumizone.


Subject(s)
Hymenoptera , Moths , Wasps , Animals , Female , Male , Semicarbazones , Sex Ratio , Spodoptera
6.
Neotrop Entomol ; 49(6): 882-892, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32632568

ABSTRACT

Rotation of insecticide modes of action is recommended to delay selection for insecticide resistance. In this study, larvae of Spodoptera frugiperda (J.E. Smith) were exposed alternately to spinetoram and metaflumizone with insecticidal and biological response determined. Five generations (G) were evaluated with at least 200 larvae assayed per treatment. The experiment consisted of rearing field-collected and untreated larvae (M-Control), larvae with successive applications of either metaflumizone (M-MET) or spinetoram (M-SPI), and alternation of these insecticides (M-Rotation treatment) consisting of the following treatments: G2 = exposure to SPI, G3 = exposure to MET, G4 = exposure to SPI, G5 = exposure to MET, and G6 = exposure to SPI. Four days after application, those surviving larvae were used to compose the following generations. In the G7, evaluations were made on the selected populations M-MET, M-SPI, M-Rotation, and control larvae to determine biological characteristics used to calculate the fertility life table parameters and further comparisons across treatments. The frequency of resistance was increased at rate of 49.5% and 29.2% after five generations of selection pressure with MET and SPI, respectively. However, rotation of insecticides reduced the frequency of resistance about 50% over the generations. Individuals originated from successive exposures to the insecticides exhibited delayed egg incubation, greater percentage of pupae with deformation, longer larval and pupal periods, and reduction in emergence rate and longevity of adults, suggesting adaptive costs associated with resistance.


Subject(s)
Insecticide Resistance , Insecticides/administration & dosage , Spodoptera , Agriculture/methods , Animals , Brazil , Macrolides , Semicarbazones
7.
Rev. bras. plantas med ; 14(spe): 183-187, 2012. tab
Article in Portuguese | LILACS | ID: lil-648545

ABSTRACT

Avaliou-se o crescimento, a produção e o teor do óleo essencial de dois cortes de capim citronela em cultivo consorciado com algodoeiro colorido no semiárido. Para isso foram utilizados dois sistemas de consórcios (tratamentos): algodão colorido consorciado com capim citronela 3x1 e algodão colorido consorciado com capim citronela 1x1. A variedade de algodão colorido utilizada foi a BRS Rubi e as mudas de capim citronela foram produzidas no Horto de Plantas Medicinais da Unimontes. O delineamento experimental utilizado foi em blocos casualizados com dois tratamentos e 16 repetições. O experimento foi mantido em regime de sequeiro e foi avaliado a altura das plantas de capim citronela. Foram realizadas duas colheitas das folhas de capim citronela, sendo a primeira no momento da colheita da fibra do algodão e a segunda na rebrota do capim, seis meses após. Todas as plantas da parcela foram colhidas e as folhas frescas foram pesadas, no campo, com o auxílio de balança digital. Amostras das folhas colhidas foram retiradas e levadas para secagem em estufa com circulação forçada de ar a 35ºC até atingirem massa constante. Foi verificada a massa seca e posteriormente realizada a extração do óleo essencial pelo método de hidrodestilação em aparelho modificado de Clevenger. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste Skott-Knott (p<0,05). A altura das plantas não diferiu entre os tratamentos nas colheitas. Para a produção de massa fresca e seca houve diferença entre os tratamentos apenas na segunda colheita. Neste caso, as plantas cultivadas em consórcio 1x1 produziram mais do que as do consórcio 3x1. O teor de óleo essencial de capim citronela não variou entre os dois sistemas de consórcio, tanto no primeiro como no segundo corte.


The research was performed to evaluate the growth, production and essential oil content of the two harvests of citronella grass in intercropped with colored cotton in semiarid.For this, was used two system consortium (treatments): colored cotton intercropped with citronella grass 3X1 and colored cotton intercropped with citronella grass 1X1. The variety of colored cotton used was BRS Rubi and the citronella grass seedlings were produced in the Medicinal Plants Garden of Unimontes. The experimental design used was randomized blocks with two treatments and 16 repetitions. The experiment was maintained under rainfed conditions. Was evaluated plant height of citronella grass. Citronella grass leaves were harvested twice: the first was made at harvest of cotton fiber and the second in the grass regrowth, six months later. All plants in the plot were harvested and the fresh leaves were weighed, in the field, with the aid of a digital balance. Samples from leaves harvested were collected and taken for drying in an oven with forced air at 35ºC until reaching constant weight. Dry mass was verified and the performed the extraction of essential oil by hydrodestilation in Clevenger modified apparatus. Data were subjected to analysis of variance and means compared by Skott-Knott test (p<0.05). The plants height did not differ between treatments in harvests. For the production of fresh and dry mass was significant difference between treatments only in the second harvest. In this case the plants cultivated in the consortium 1x1 produced more than in the consortium 3x1. The essential oil content of citronella grass did not vary between the two systems consortium, in the first and the second harvest.


Subject(s)
Oils, Volatile/analysis , Gossypium/growth & development , Cymbopogon/growth & development , Analysis of Variance
8.
Parassitologia ; 47(1): 165-9, 2005 Mar.
Article in English | MEDLINE | ID: mdl-16044686

ABSTRACT

The spatial distribution of American visceral leishmaniasis (VL) was studied within the context of the environmental characteristics of northwest Bahia State in Brazil during an epidemic year. Geographic Information Systems (GIS) and Remote Sensing (RS) were used to characterize the landscape epidemiology of VL in order to identify and map high risk areas and endemic zones in a northwestern Bahia study area. Normalized Difference Vegetation Index (NDVI) was shown to be one of the most important risk factors in the area of study. Low NDVI values were related to high numbers of sand flies and high numbers of human and canine VL positive cases. Caatinga vegetation type was the dominant vegetation type in the endemic area. The use of RS and GIS allowed the identification of classes of VL risk that may be useful information to guide control program interventions.


Subject(s)
Environmental Monitoring , Geographic Information Systems , Leishmaniasis, Visceral/epidemiology , Satellite Communications , Animals , Brazil/epidemiology , Climate , Dog Diseases/epidemiology , Dog Diseases/parasitology , Dog Diseases/transmission , Dogs , Ecosystem , Endemic Diseases , Environmental Monitoring/instrumentation , Environmental Monitoring/methods , Epidemiological Monitoring , Humans , Incidence , Insect Vectors/parasitology , Leishmania donovani/isolation & purification , Leishmaniasis, Visceral/transmission , Leishmaniasis, Visceral/veterinary , Plants , Psychodidae/parasitology , Risk , Risk Factors , Urban Health
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