RESUMO
Abstract Earias vittellaFabricius, 1794 (Noctuidae: Lepidoptera) is deliberated to be one of the most destructive pests of cotton and okra vegetation in the world including Asia. The pest has established resistance to various synthetic insecticides. The use of bio-pesticide is one of the unconventional approaches to develop a vigorous ecosystem without harming non- target pests and beneficial natural insect fauna. In the present study, the toxicity levels of Citrullus colocynthis seed extract have been evaluated against the populations of E. vittellaunder standardized laboratory conditions. The toxic effects of C. colocynthis on development periods, protein contents and esterase activity of the life stages of E. vittella were also evaluated. The toxicity levels of methanol, ethanol, hexane, water and profenofos were evaluated on the 1st instar larvae of E. vittella. LC30 and LC80 concentrations exhibited the effectiveness of methanol-based C. colocynthis seed extract against 1st instar larvae of E. vitella. The enhanced larval and pupal periods were revealed in treated samples during the comparison with untreated samples. The intrinsic rate of increase, net reproductive rate in the LC30 and LC80 concentrations exposed larvae remained less than the control treatment. Fecundity, the esterase activity and protein contents were declined in LC30 and LC80 treated samples as compared to the control. The present findings suggest that C. colosynthis extracts based botanical insecticides are beneficial, ecosystem sustainable and can be integrated with insect management programs from environment safety perspective.
Resumo Earias vittella Fabricius, 1794 (Noctuidae: Lepidoptera) é considerada uma das pragas mais destrutivas de algodão e quiabo no mundo, incluindo a Ásia. Essa praga estabeleceu resistência a vários inseticidas sintéticos. O uso de biopesticidas é uma das abordagens não convencionais para desenvolver um ecossistema saudável sem prejudicar as pragas não alvo e a fauna natural benéfica de insetos. No presente estudo, os níveis de toxicidade do extrato de semente de Citrullus colocynthis foram avaliados nas populações de E. vittella em condições de laboratório padronizadas. Os efeitos tóxicos de C. colocynthis nos períodos de desenvolvimento, conteúdo de proteína e atividade esterase das fases de vida de E. vittella também foram avaliados. Os níveis de toxicidade de metanol, etanol, hexano, água e profenofós foram avaliados em larvas de 1º instar de E. vittella. As concentrações de LC30 e LC80 apresentaram eficácia do extrato de sementes de C. colocynthis à base de metanol contra larvas de 1º instar de E. vittella. Os períodos larval e pupal aumentados foram revelados nas amostras tratadas durante a comparação com as amostras não tratadas. A taxa intrínseca de aumento e a taxa reprodutiva líquida nas concentrações de larvas expostas LC30 e LC80 permaneceram menores do que o tratamento controle. A fecundidade, a atividade da esterase e o conteúdo de proteína diminuíram nas amostras tratadas com LC30 e LC80 em comparação com o controle. As presentes descobertas sugerem que os extratos de C. colocynthis à base de inseticidas botânicos são benéficos, sustentáveis para o ecossistema e podem ser integrados com programas de manejo de insetos do ponto de vista da segurança ambiental.
RESUMO
Abstract Earias vittellaFabricius, 1794 (Noctuidae: Lepidoptera) is deliberated to be one of the most destructive pests of cotton and okra vegetation in the world including Asia. The pest has established resistance to various synthetic insecticides. The use of bio-pesticide is one of the unconventional approaches to develop a vigorous ecosystem without harming non- target pests and beneficial natural insect fauna. In the present study, the toxicity levels of Citrullus colocynthis seed extract have been evaluated against the populations of E. vittellaunder standardized laboratory conditions. The toxic effects of C. colocynthis on development periods, protein contents and esterase activity of the life stages of E. vittella were also evaluated. The toxicity levels of methanol, ethanol, hexane, water and profenofos were evaluated on the 1st instar larvae of E. vittella. LC30 and LC80 concentrations exhibited the effectiveness of methanol-based C. colocynthis seed extract against 1st instar larvae of E. vitella. The enhanced larval and pupal periods were revealed in treated samples during the comparison with untreated samples. The intrinsic rate of increase, net reproductive rate in the LC30 and LC80 concentrations exposed larvae remained less than the control treatment. Fecundity, the esterase activity and protein contents were declined in LC30 and LC80 treated samples as compared to the control. The present findings suggest that C. colosynthis extracts based botanical insecticides are beneficial, ecosystem sustainable and can be integrated with insect management programs from environment safety perspective.
Resumo Earias vittella Fabricius, 1794 (Noctuidae: Lepidoptera) é considerada uma das pragas mais destrutivas de algodão e quiabo no mundo, incluindo a Ásia. Essa praga estabeleceu resistência a vários inseticidas sintéticos. O uso de biopesticidas é uma das abordagens não convencionais para desenvolver um ecossistema saudável sem prejudicar as pragas não alvo e a fauna natural benéfica de insetos. No presente estudo, os níveis de toxicidade do extrato de semente de Citrullus colocynthis foram avaliados nas populações de E. vittella em condições de laboratório padronizadas. Os efeitos tóxicos de C. colocynthis nos períodos de desenvolvimento, conteúdo de proteína e atividade esterase das fases de vida de E. vittella também foram avaliados. Os níveis de toxicidade de metanol, etanol, hexano, água e profenofós foram avaliados em larvas de 1º instar de E. vittella. As concentrações de LC30 e LC80 apresentaram eficácia do extrato de sementes de C. colocynthis à base de metanol contra larvas de 1º instar de E. vittella. Os períodos larval e pupal aumentados foram revelados nas amostras tratadas durante a comparação com as amostras não tratadas. A taxa intrínseca de aumento e a taxa reprodutiva líquida nas concentrações de larvas expostas LC30 e LC80 permaneceram menores do que o tratamento controle. A fecundidade, a atividade da esterase e o conteúdo de proteína diminuíram nas amostras tratadas com LC30 e LC80 em comparação com o controle. As presentes descobertas sugerem que os extratos de C. colocynthis à base de inseticidas botânicos são benéficos, sustentáveis para o ecossistema e podem ser integrados com programas de manejo de insetos do ponto de vista da segurança ambiental.
Assuntos
Animais , Citrullus colocynthis , Inseticidas , Mariposas , Extratos Vegetais/farmacologia , Ecossistema , LarvaRESUMO
ABSTRACT Parasitoids of the genus Trichogramma are promising for the biological control of insect pests in several crops, including cassava, which is severely attacked by Erinnyis ello L., 1758 (Lepidoptera: Sphingidae). Evaluating the biological aspects of these parasitoids to understand their dynamics is an important step towards the implementation of this control strategy in the field. Thus, our objective was to evaluate the biology of Trichogramma manicobai Brun, Moraes & Soares, 1984, and T. marandobai Brun, Moraes & Soares, 1986 in E. ello eggs. The parasitoids were obtained by collecting E. ello eggs from a commercial production of cassava, and the host's eggs were obtained from laboratory and greenhouse rearings. The average duration of a generation (T), net reproduction rate (R0), intrinsic rate of increase (rm), and the finite rate of increase (λ) were estimated, and from these, the fertility life table was calculated. The results indicated that T. marandobai has both higher net reproduction rate and a higher intrinsic rate of increase as well as requires less time to double its population than T. manicobai. Thus, T. marandobai has potential for natural and conservative biological control of E. ello. In addition, its potential in applied biological control should be evaluated through studies on the viability of its mass rearing in alternative hosts and its dispersion behavior in the field.
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A presente nota de pesquisa estima o impacto das mortes por Covid-19 sobre a esperança de vida no Brasil e regiões para os primeiros seis meses de 2020. Com base nos dados do Datasus e nas tábuas de vida com decremento simples, estimou-se que as mortes por Covid-19 ocorridas até 18 de agosto de 2020 tiveram impacto estatisticamente negativo na esperança de vida ao nascer, tanto masculina (-1,05 ano) quanto feminina (-0,85 ano). Em termos regionais, a maior perda em anos de vida é estimada no Norte (-1,65 ano para homens e -1,48 ano para mulheres), enquanto o Sul foi a região com menor impacto (-0,5 ano para homens e -0,36 para mulheres). Os resultados do modelo logístico para o país apontam que a mortalidade por Covid-19 tende a ser maior entre a população com mais de 65 anos, homens, pretos e de baixa instrução. As comorbidades aumentam a chance de desfecho morte, especialmente doença hepática e renal crônica. Tais análises foram ainda desagregadas por grandes regiões brasileiras.
This research note estimates the impact of deaths by Covid-19 on life expectancy in Brazil and the Regions for the first six months of 2020. Based on data from Datasus and the decreasing life tables, it was estimated that deaths by Covid-19 that occurred until August 18, 2020 had a statistically negative impact on life expectancy at birth, both male (-1.05 years) and female (-0.85 years). In regional terms, the greatest loss in years of life is estimated in the North (-1.65 years for men and -1.48 years for women), while in the South it was -0.5 year for men and -0.36 for women. The results of the logistic model for the country show that Covid-19 mortality tends to be higher among males, blacks, people with low education level and people over 65 years old. Comorbidities increase the chance of death, especially liver disease and chronic kidney disease. Such analyzes were further disaggregated by large Brazilian regions.
Esta nota de investigación estima el impacto de las muertes por Covid-19 en la esperanza de vida en Brasil y sus regiones durante los primeros seis meses de 2020. Con base en los datos de Datasus y de las tablas de vida decrecientes, se estimó que las muertes por Covid-19 que ocurrieron hasta el 18 de agosto de 2020 tuvieron un impacto estadísticamente negativo en la esperanza de vida al nacer, tanto en hombres (−1,05 años) como en mujeres (−0,85 año). En términos regionales, la mayor pérdida en años de vida se estima en el Norte (−1,65 año para los hombres y −1,48 años para las mujeres), mientras que en el Sur fue de −0,5 años para los hombres y −0,36 para las mujeres. Los resultados del modelo logístico para el país muestran que la mortalidad por Covid-19 tiende a ser mayor entre la población mayor de 65 años, hombres, afrobrasileros y de bajo nivel educativo. Las comorbilidades aumentan la probabilidad de muerte, especialmente la enfermedad hepática y la enfermedad renal crónica. Dichos análisis se desglosaron aun más por grandes regiones brasileñas.
Assuntos
Humanos , Fatores Socioeconômicos , Brasil , Mortalidade , Tábuas de Vida , COVID-19/mortalidade , Expectativa de Vida , PandemiasRESUMO
ABSTRACT Vatiga manihotae (Drake 1922) (Hemiptera: Tingidae) is an important cassava pest due to the great potential damage and the increasing population in recent years. However, few studies about bioecology and control of the cassava lace bug have been conducted and their results don't provide adequate control strategies. An alternative to maintain the population below economic injury levels is through the adoption of host plant resistance. To improve the understanding about the bioecology and find new sources of resistance in cassava, the biological parameters and demographics of V. manihotae on five cassava genotypes (Santa Helena, MEcu 72, Col 22, Clone 02 and Clone 03) under controlled conditions (25±2°C, 14L/10D) were evaluated. Duration and viability of the stages, the period egg-adult, sex ratio, the pre-oviposition period, fecundity and longevity of male and female was determined, and a fertility life table was prepared. Insects fed on MEcu 72 showed increased nymphal, egg-adult, and pre-oviposition periods and reduced female fecundity and longevity in comparison to the other genotypes. Demographic parameters (Ro, rm, T, DT) showed a significant impact on the growth potential of V. manihotae fed on MEcu 72 indicating that the populations would diminish over time. The combined effect of these parameters indicated that MEcu 72 has resistance on V. manihotae specimens hindering their development.
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The survival of eggs and nymphs of Diaphorina citri Kuwayama (Hemiptera: Liviidae) was estimated on young plants (< 1 year) of Citrus sinensis (cultivar Valencia) grafted on Citrus limonia in 3 seasons (Winter and Spring 2013; and Autumn 2014) in Ribeirão Preto, São Paulo State, Brazil. Young shoots with eggs were selected from natural or artificial infestations. Eggs, small nymphs (1st to 3rd instar), and large nymphs (4th and 5th instar) were counted every 3 days. Shoots with large nymphs were caged until the emergence of the adults. The lowest eggs and nymph survival were observed during Winter (0.0%), and Autumn (0.4%); the highest survival rates were recorded during Spring (12.2%). The biotic factor of mortality identified was the parasitism of large nymphs by Tamarixia radiata Waterston (Hymenoptera: Eulophidae), observed in all seasons. Air temperatures (minimum and maximum), and air relative humidity (minimum) could not explain the immature survival differences between Spring (12.2%) and Autumn (0.4%). Rainfall during Spring (165 mm) was higher than during Autumn (48 mm) and may have favored the survival of D. citri in the Spring. Adverse abiotic factors seem to be more important on immature D. citri survival than the biotic factor (parasitism).(AU)
A sobrevivência de ovos e ninfas de Diaphorina citri Kuwayama (Hemiptera: Liviidae) foi estimada em plantas jovens (< 1 ano) de Citrus sinensis (cultivar Valencia) enxertadas em Citrus limonia em 3 estações (inverno e primavera de 2013, e outono de 2014) em Ribeirão Preto, estado de São Paulo, Brasil. Ramos novos com ovos foram selecionados a partir de infestações naturais ou artificiais. Ovos, ninfas pequenas (ínstar 1 ao 3) e ninfas grandes (ínstar 4 e 5) foram contados a cada 3 dias. Ramos com ninfas grandes foram colocados em gaiolas até a emergência dos adultos. As menores sobrevivências de ovos e ninfas foram observadas no inverno (0,0%) e no outono (0,4%), e a maior sobrevivência ocorreu na primavera (12,2%). O principal fator biótico de mortalidade identificado foi o parasitismo de ninfas grandes por Tamarixia radiata Waterston (Hymenoptera: Eulophidae), observado em todas as estações. As temperaturas (mínima e máxima) e umidade relativa (mínima) do ar não explicaram as diferenças nas sobrevivências de imaturos entre a primavera (12,2%) e o outono (0,4%). As chuvas na primavera (165 mm) foram maiores que no outono (48 mm) e podem ter favorecido a sobrevivência de D. citri na primavera. Fatores abióticos adversos parecem ser mais importantes na sobrevivência de imaturos de D. citri que o fator biótico (parasitismo).(AU)
Assuntos
Mortalidade , Citrus , Ninfa , Citrus sinensis , HemípterosRESUMO
Resumen El conocimiento de la dinámica de poblaciones provee información sobre la historia reciente, el estado actual y la tendencia futura de una población. Physalaemus biligonigerus es un anuro con una amplia distribución en el Neotrópico, presenta una actividad reproductiva elevada y explosiva, pero sus poblaciones parecen estar compuestas por individuos jóvenes. El objetivo de este estudio fue analizar la demografía poblacional de P. biligonigerus en una charca semipermanente en Río Cuarto, Córdoba, Argentina y realizar una proyección poblacional a 30 generaciones. Se determinó la estructura de edad utilizando esqueletocronología, y posteriormente se construyó una tabla de vida estática. Se calculo la fecundidad y las tasas de supervivencia para cada estadío con los que se construyó una Matriz de Leslie y se realizó la proyección poblacional. La proyección muestra oscilaciones en el número de individuos pero a pesar de esto, la tendencia final de la población es a un aumento en su tamaño. La mayor proporción de supervivientes se da en las fases de huevos a larvas, y la fuerza de mortalidad actúa con intensidad sobre la fase de larvas. La tasa neta reproductiva indica que la población de P. biligonigerus de la charca en estudio está en incremento.
Abstract Knowledge of population dynamics provides information on the recent history, current status, and future trends of a population. Physalaemus biligonigerus is widely distributed in the Neotropics, this anuran has a high and explosive reproductive activity, but its populations seem to be composed of young individuals. The objective of this study was to analyze the population demography of P. biligonigerus in a semipermanent pond in Río Cuarto, Córdoba, Argentina and to carry out a population projection through 30 generations. The age structure was determined from the use of skeletochronology, and a static life table was later made. Fertility and survival rates were calculated for each stage, by which a Leslie Matrix was constructed and the population projection was performed. The projection shows oscillations in the number of individuals but in spite of this, the final tendency of the population is an increase in its size. The highest proportion of survivors occurs in the egg-to-larval stages and the mortality force acts intensively on the larval phase. The net reproductive rate indicates that the population of P. biligonigerus of the study pond is increasing. Rev. Biol. Trop. 66(2): 765-775. Epub 2018 June 01.
Assuntos
Animais , Anuros/anatomia & histologia , Desenvolvimento Ósseo/fisiologia , Anfíbios/crescimento & desenvolvimento , ArgentinaRESUMO
Abstract The soybean (Glycine max (L.): Fabaceae) is considered the most important agricultural crop in Brazil. Phytophagous tetranychid mites as Mononychellus planki McGregor, Tetranychus ludeni Zacher and T. urticae Koch have been considered pest in soybean crops. Neoseiulus idaeus Denmark & Muma (Phytoseiidae) is a predatory mite of T. ludeni and T. urticae. The aim of the present study was to evaluate the biological performance of N. idaeus when fed on T. urticae, T. ludeni and M. planki, coming from the Northwest region of Rio Grande do Sul state, Brazil. The study was conducted in the laboratory with individual predators supplied with different preys. The mean duration (days) of N. idaeus egg-adult development was similar independently of supplied prey (T. ludeni - 5.29±0.03; M. planki - 5.34±0.05 and T. urticae - 5.23±0.03 days). Female viability was 90% when fed on M. planki and 100% when fed on T. ludeni and T. urticae. Mean fecundity of N. idaeus was lower when fed on M. planki (4.6±1.58 eggs/female) and higher when fed on T. ludeni (21.8±3.22) and T. urticae (26.2±2.41). The mean generation time (T) was lower when N. idaeus fed on M. planki than when fed on T. ludeni and T. urticae. The net reproductive rate (Ro) was 4.42±0.49 on M. planki, 17.77±0.55 on T. ludeni and 20.59±0.48 on T. urticae. The innate capacity for increase (rm) was lower when N. idaeus was fed on M. planki (0.09) and higher when such predator was fed on T. ludeni (0.20) and T. urticae (0.22 females/females/day). These results demonstrated that N. idaeus is able to reach the complete development feeding on all the three tetranychid species. Mononychellus planki demonstrated to provide a sub-optimal diet if compared to T. ludeni and T. urticae.
Resumo Soja (Glycine max (L.): Fabaceae) é a mais importante cultura agrícola brasileira. Tetraniquídeos fitófagos são pragas na cultura, Mononychellus planki McGregor, Tetranychus ludeni Zacher e T. urticae Koch. Neoseiulus idaeus Denmark & Muma (Phytoseiidae) é o ácaro predador de T. ludeni e T. urticae. Este estudo teve como objetivo avaliar o desempenho biológico de N. idaeus quando alimentado com T. urticae, T. ludeni e M. planki da região noroeste do Rio Grande do Sul, Brasil. O estudo foi realizado em laboratório com predadores individualizados com diferentes presas. A duração média (dias) de N. idaeus desenvolvimento ovo-adulto foi semelhante independentemente da presa fornecida (T. ludeni - 5.29 ± 0.03; M. planki - 5.34 ± 0.05 e T. urticae - 5.23 ± 0.03 dias). Viabilidade feminina foi de 90% quando alimentados com M. planki e 100% em T. ludeni e T. urticae. Fecundidade de N. idaeus foi menor com M. planki (4.6 ± 1.58 ovos / fêmea) e maior com T. ludeni e T. urticae, 21.8 ± 3.22 e 26.2 ± 2.41, respectivamente. O tempo médio de uma geração (T) foi menor quando N. idaeus alimentados com M. planki do que quando em T. ludeni e T. urticae. A taxa líquida de reprodução (Ro) foi de 4.42 ± 0.49 em M. planki, 17.77 ± 0.55 em T. ludeni e 20.59 ± 0.48 no T. urticae. A capacidade inata de aumento (rm) foi menor em M. planki (0.09) e maior quando alimentados com T. ludeni (0.20) e T. urticae (0.22 fêmeas / fêmea / dia). Estes resultados demonstraram que N. idaeus é capaz de utilizar e desenvolver em todas as três espécies de tetraniquídeos. Mononychellus planki demonstrou ser a presa menos adequada para este predador do que T. urticae e T. ludeni.
Assuntos
Animais , Masculino , Feminino , Glycine max , Controle Biológico de Vetores , Ácaros/fisiologia , Reprodução , Brasil , Produtos Agrícolas , Tetranychidae/crescimento & desenvolvimento , Tetranychidae/fisiologia , Fertilidade , Ácaros/crescimento & desenvolvimentoRESUMO
Abstract Predatory mites that belong to the Phytoseiidae family are one of the main natural enemies of phytophagous mites, thus allowing for their use as a biological control. Phytoseiulus macropilis (Banks, 1904) (Acari: Phytoseiidae) is among the main species of predatory mites used for this purpose. Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) is considered to be one of the most important species of mite pests and has been described as attacking over 1,100 species of plants in 140 families with economic value. The objective of the present study was to investigate, in the laboratory, the reproductive parameters of the predatory mite P. macropilis when fed T. urticae. Experiments were conducted under laboratory conditions at 25 ± 2 °C of temperature, 70 ± 10% RH and 14 hours of photophase. In addition, biological aspects were evaluated and a fertility life table was established. The results of these experiments demonstrated that the longevity of adult female was 27.5 days and adult male was 29.0 days. The population was estimated to increase approximately 27 times (Ro) in mean generation time (T), which was 17.7 days. Lastly, the mite population grew 1.2 times/day (λ) and doubled every 3.7 days (TD).
Resumo Os ácaros predadores pertencentes à família Phytoseiidae constituem um dos principais inimigos naturais de ácaros fitófagos, o que possibilita o seu uso em controle biológico. Entre as principais espécies destaca-se Phytoseiulus macropilis (Banks, 1904) (Acari: Phytoseiidae). O ácaro Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) é considerado uma das espécies de ácaros-praga mais importantes, atacando mais de 1.100 espécies de plantas em 140 famílias de valor econômico. Este trabalho foi realizado com o objetivo de estudar, em laboratório, os parâmetros reprodutivos do ácaro predador P. macropilis, quando alimentado com T. urticae. Os estudos foram conduzidos em laboratório à temperatura de 25 ± 2 °C, 70 ± 10% de UR e 14 horas de fotofase e foram avaliados os aspectos biológicos e confeccionada a tabela de vida de fertilidade. Foi constatada uma longevidade de 27,5 dias para fêmeas adultas e 29,0 dias para machos. A população foi estimada em aumentar aproximadamente 27 vezes (Ro) no período médio de duração de geração (T) que foi de 17,7 dias. A população do ácaro cresceu 1,2vezes/dia (λ) e dobrou a cada 3,7 dias (TD).
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Animais , Masculino , Feminino , Reprodução , Tetranychidae , Longevidade , Ácaros/fisiologiaRESUMO
Abstract This study provides the first contribution of the biology and life table of Aphis forbesi Weed, 1889 (Hemiptera: Aphididae), an important strawberry pest throughout the world. This species lives in the crown and leaf petioles of the plant. It is difficulty to rear this species in laboratory due to protocooperation with ants observed only in the field. We studied the life cycle of A. forbesi on the leaves of the Albion strawberry cultivar at 25 ± 2 °C, 60 ± 10% relative humidity, and a 12-h photophase. The experiment was randomised with 100 replicates. The parameters of the fertility life table were calculated using TabVida. In the population studied, 25% and 46% had four and three instars, respectively. A mean of 1.43 nymphs per female per day was generated. The mean reproductive period was seven days and the mean longevity was 10 days. In every 11 days there is a generation of A. forbesi, where each female has the potential to generate between 6 to 9 individuals daily, increasing its population by 1.2 times. The average life cycle was 16.8 days. High viability observed in all instars and the resulting values of R0, rm and λ suggest that A. forbesi has the capacity to increase their numbers in a short period of time, while generating high populations in strawberry crops, requiring differential management.
Resumo Este trabalho apresenta a primeira contribuição ao estudo de biologia e tabela de vida de fertilidade de Aphis forbesi, Weed, 1889 (Hemiptera: Aphididae), uma importante praga de morangueiro no mundo. Esta espécie se desenvolve na coroa e pecíolo do morangueiro. O desenvolvimento desta espécie em laboratório apresentou dificuldades, possivelmente devido à protocooperação com formigas, observada em campo durante coletas. O ciclo de vida de A. forbesi foi estudado em folhas de morangueiro cultivar ‘Albion’ a 25 ± 2 °C, 60 ± 10% umidade relativa, e fotofase de 12 horas. O experimento foi inteiramente casualizado com 100 repetições. Os parâmetros da tabela de vida de fertilidade foram calculados usando o software TabVida. Na população estudada observou-se que as ninfas apresentaram três e quatro instares, sendo 46 e 25% respectivamente, dos indivíduos que completaram o ciclo de vida. Foi gerada uma média de 1,43 ninfas/ fêmea/ dia. O período reprodutivo médio foi de 7 dias e a longevidade média 10 dias. A cada 11 dias ocorre uma geração de A. forbesi onde cada fêmea tem capacidade de gerar de 6 a 9 indivíduos aumentando em 1,2 vezes a população. O ciclo de vida de A. forbesi durou em média 16,8 dias. A alta viabilidade observada em todos os estádios, e os valores de R0, rm e λ sugerem que A. forbesi tem a capacidade de aumentar seu número em um curto período de tempo, gerando altas populações no cultivo do morangueiro, exigindo manejo diferenciado.
Assuntos
Animais , Feminino , Afídeos/crescimento & desenvolvimento , Fragaria , Reprodução , Tábuas de Vida , Fertilidade , Longevidade , Ninfa/crescimento & desenvolvimentoRESUMO
ABSTRACT The biology, reproductive variables and population growth indicators of Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) fed on three diets, namely Cinara atlantica (Wilson, 1919) (Hemiptera: Aphididae), Brevicoryne brassicae (Linnaeus, 1758) (Hemiptera: Aphididae), and frozen eggs of Anagasta kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae), were evaluated. With all three diets, birth rate was higher than mortality, resulting in positive rm values and thus indicating population growth. Under the conditions used in the experiments, H. axyridis was able to survive, develop and reproduce normally. This demonstrates that are different kind of food that can be essential for supporting the reproduction of some species of Coccinellidae, but not with the same optimization of preferred prey.
RESUMO
La garantía de la salud en el orden político inglés decimonónico en el cual la duración media de la vida estaba determinada por la situación del individuo en la estructura de clases, no era posible ante un estado carente de organismos sanitarios de administración y control de la salubridad pública, además del influjo arrollador del sector económico egoísta, individualista y privatizador, y por la ausencia de ciudadanía activa que propiciara la agencia de espacios de acción colectiva y de acción política. Fue necesario el advenimiento de artefactos matemáticos como la tabla de supervivencia, para convencer al cuerpo social y político liberal de la época de la posibilidad de cada vez más y mejor vida, e iniciar la larga marcha de la participación política democrática hacia el estatus de ciudadano. (Acta Med Colomb 2015; 40: 326-330).
The guarantee of health in the nineteenth-century English political order in which the average length of life was determined by the status of the individual in the class structure, was not possible in front of a state devoid of health management organizations an health public control, in addition to the overwhelming influence of a selfish, individualist and privatizing economic sector, and the absence of active citizenship which could foster the management of collective and political action spaces. The advent of mathematical artifacts such as table survival was necessary to convince the liberal social and political body of the epoch of the possibility of getting more and better life, and begin the long march of democratic political participation towards the status of citizens. (Acta Med Colomb 2015; 40: 326-330).
Assuntos
Gestão em Saúde , Organização e Administração , Participação da Comunidade , Estado , SobrevivênciaRESUMO
Este trabajo describe los parámetros biológicos y poblacionales del pulgón negro, Aphis craccivora Koch, sobre fríjol caupí (Vigna unguiculata (L. Walp.)), bajo condiciones de laboratorio. Los insectos se criaron sobre plántulas individualizadas a una temperatura promedio de 28 °C, humedad relativa de 70 % y fotoperiodo de 12 horas. Los parámetros medidos fueron periodo ninfal, fecundidad, supervivencia, periodo pre-reproductivo y aspectos relativos a la tasa de crecimiento del áfido. La tasa reproductiva neta R (0) fue 66,00, la tasa intrínseca de crecimiento del áfido (r m) fue 0,51, el tiempo de duplicación de la población (TD) fue 2,3. Se analizaron las curvas de supervivencia (lx), fecundidad (mx), la duración del período ninfal y reproductivo del áfido. Los resultados difieren de los realizados en otras variedades de fríjol caupí, evidenciándose la susceptibilidad de la variedad criolla usada por los agricultores en la costa Caribe colombiana.
This research describes the population and biological parameters of the black aphid (Aphis craccivora Koch) on cowpea bean (Vigna unguiculata (L. Walp.)), under laboratory conditions. The insects were raised on individualized seedlings in an average temperature of 28 °C, at 70 % relative humidity during a photoperiod of 12 hours. The parameters measured were the nymphal period, fecundity, longevity, pre-reproductive period and aspects of aphid growth rate. The net reproductive rate R (0) was 66.00, the intrinsic g rate of increase of the aphid (rm) was 0.51, and the population doubling time (TD) was 2.3. Survival curves (lx), fecundity (mx), the duration of nymphal and the reproductive period of the aphid were analyzed. The results differ from those found in other varieties of cowpea beans, demonstrating the susceptibility of the native variety used by farmers in the Colombian Caribbean coast.
RESUMO
The predatory mite, Neoseiulus californicus (McGregor, 1954) (Acari: Phytoseiidae) is one of the principal natural enemies of tetranychid mites in several countries, promoting efficient control of those mites in several food and ornamental crops. Pest attacks such as that of the spider mite, Tetranychus urticae Koch, 1836 (Acari: Tetranychidae), is one of the problems faced by farmers, especially in the greenhouse, due to the difficulty of its control with the use of chemicals because of the development of fast resistance making it hard to control it. The objective of this work was to study the life history of the predatory mite N. californicus as a contribution to its mass laboratory rearing, having castor bean plant [Ricinus communis L. (Euphorbiaceae)] pollen as food, for its subsequent use as a natural enemy of T. urticae on a cultivation of greenhouse rosebushes. The studies were carried out in the laboratory, at 25 ± 2°C of temperature, 70 ± 10% RH and a 14 hour photophase. The biological aspects and the fertility life table were appraised. Longevity of 32.9 days was verified for adult females and 40.4 days for males. The intrinsic rate of increase (rm) was 0.2 and the mean generation time (T) was 17.2 days. The population doubled every 4.1 days. The results obtained were similar to those in which the predatory mite N. californicus fed on T. urticae.
O ácaro predador, Neoseiulus californicus (McGregor, 1954) (Acari: Phytoseiidae) é um dos principais inimigos naturais de ácaros tetraniquídeos em vários países, promovendo um eficiente controle em várias culturas alimentícias e ornamentais. O ataque de pragas como o ácaro-rajado, Tetranychus urticae Koch, 1836 (Acari: Tetranychidae), é um dos problemas enfrentados pelos produtores, principalmente em casa de vegetação, pela dificuldade de seu controle com o uso de agroquímicos devido ao rápido desenvolvimento de resistência o que dificulta seu controle. Foi objetivo deste trabalho estudar a história de vida do ácaro predador N. californicus como contribuição à sua criação massal em laboratório tendo como alimento pólen de mamoneira [Ricinus communis L. (Euphorbiaceae)] para posterior uso como inimigo natural de T. urticae em cultivo de roseiras (Rosa spp.) em casa de vegetação. Os estudos foram conduzidos em laboratório à temperatura de 25 ± 2°C, 70 ± 10% de UR e 14 horas de fotofase. Foram avaliados os aspectos biológicos e confeccionada a tabela de vida de fertilidade. Foi constatada uma longevidade de 32,9 dias para fêmeas adultas e 40,4 dias para machos. A estimativa da capacidade inata de crescimento da população (rm) foi 0,2 dias e a duração média de geração (T) foi 17,2 dias. A população dobrou a cada 4,1 dias. Os resultados obtidos foram semelhantes àqueles nos quais o predador N. californicus foi alimentado com T. urticae.
Assuntos
Animais , Feminino , Masculino , Ácaros e Carrapatos/crescimento & desenvolvimento , Ricinus communis , Pólen , Ácaros e Carrapatos/classificação , Laboratórios , Estágios do Ciclo de Vida , Controle Biológico de Vetores/métodosRESUMO
The aim of this work was to construct life table of Bemisia tabaci (Gen.) A and B (silverleaf whitefly B. argentifolii Bellows and Perring) biotype (Hem.: Aleyrodidae) on two host plants; cotton, (Gossypium hirsutum L.) and rapeseed, (Brassica napus L.). Experiments were conducted in a growth chamber under 24 ± 2ºC, 55±3% RH and 16:8 (L:D) h photoperiod on caged plants of cotton G. hirsutum L. (Varamin 76 variety) and rapeseed B. napus L. (global variety. The intrinsic rate of natural increase (r m), net reproductive rate (R0) and mean generation time (T) for B. tabaci A biotype was 0.1010 females per female per day, 18.4075 females per female and 30.079 day (d) on cotton; 0.1286, 30.6760 and 26.77 d on rapeseed; and for B biotype (B. argentifolii) those above respective parameters averaged 0.1033, 27.8426 and 32.74 d on cotton and 0.1750, 40.75 and 21.27 d on rapeseed. The total survival of A and B biotype from the egg to adult on cotton was 22.08 and 22.25, respectively. The results showed significant differences between the two biotype reared on either host plant for gross reproductive rate (GRR), net reproductive rate (R0 or NRR), intrinsic rates of increase (r m), finite rate of increase (λ), doubling time (DT) and mean generation times (Tc). To obtain a better understanding of the biology of these biotypes, Stable age distribution (Cx) and some other aspects of life history related to their hosts were also studied. Based upon the results, both biotypes showed a greater reproduction capacity on rapeseed than on cotton. Thus, rapeseed was more suitable host than cotton for two biotypes and this was an important factor in host plant selection for optimizing the control strategies of these major pests.
RESUMO
Life tables and survival curves of tadpoles from Rhinella icterica species were studied in the laboratory, under abiotic conditions controlled by a purification filter, a timer and a chiller. The survival curve for larval stage confirms a great mortality trend in the initial stages, which decreases when reaching the mature morphological condition (r = –0.94). Stages 37, 38, 39, 40 and 41 showed gradual values for their age structures, while stages 42, 43 and 44 presented high variations. Based on the results under laboratory conditions, it can be concluded that the maturity of R. icterica tadpoles development between 37 and 44 stages has a negative correlation and their predicted life expectancy is a logarithmic growth curve (y=–761.96Ln(x)+5298.5).
Tabelas de vida e curvas de sobrevivência em estágios larvais de girinos da espécie Rhinella icterica foram estudadas em laboratório, sob condições abióticas controladas com uso de filtro de depuração, timer e chiller. A curva de sobrevivência por estágio larval confirma a tendência de maior mortalidade para os estágios iniciais e menor mortalidade para o avanço da condição morfológica madura (r = –0,94). Os estágios 37, 38, 39, 40 e 41 apresentaram valores gradativos para sua estrutura etária, enquanto nos estágios 42, 43 e 44 ocorreram variações acentuadas. Com base nos resultados obtidos, nas condições de laboratório, pode-se concluir que a maturidade de desenvolvimento de girinos de R. icterica entre os estágios 37 e 44, apresenta correlação negativa e a predição de esperança de vida a uma curva logarítmica de crescimento (y=–761,96Ln(x)+5298,5).
Assuntos
Animais , Bufonidae/fisiologia , Longevidade/fisiologia , Bufonidae/classificação , Bufonidae/crescimento & desenvolvimento , Laboratórios , Modelos BiológicosRESUMO
Developmental biology, polymorphism and ecological aspects of Stiretrus decemguttatus (Hemiptera, Pentatomidae), an important predator of cassidine beetles. Stiretrus decemguttatus is an important predator of two species of cassidine beetles, Botanochara sedecimpustulata (Fabricius, 1781) and Zatrephina lineata (Fabricius, 1787) (Coleoptera, Cassidinae), on the Marajó Island, Brazil. It attacks individuals in all development stages, but preys preferentially on late-instar larvae. Its life cycle in the laboratory was 43.70 ± 1.09 days, with an egg incubation period of six days and duration from nymph and adult stages of 16.31 ± 0.11 and 22.10 ± 1.67 days, respectively. The duration of one generation (T) was 12.65 days and the intrinsic population growth rate (r) 0.25. These data reveal the adjustment of the life cycle of S. decemgutattus with those of the two preys, but suggest greater impact on Z. lineata. However, no preference over cassidine species was shown in the laboratory. Up to 17 different color patterns can be found in adults of S. decemguttatus, based on combinations of three basic sets of color markings. Some of them resemble the markings of chrysomelids associated with Ipomoea asarifolia (Convolvulaceae) and are possibly a mimetic ring. Three color patterns were identified in nymphs, none of which was associated with any specific adult color pattern.
RESUMO
Background & objectives: In Egypt, Phlebotomus papatasi is the main vector of cutaneous leishmaniasis. In nature, P. papatasi feeds on blood from different hosts and sucrose (other sugars) mainly from fig fruits. The aim of this study was to examine the effects of three food regimes on the life table parameters of females mainly the life expectancy as a factor determining the fly’s capability for Leishmania transmission. Methods: Females maintained on different diets (30% sucrose solution, Guinea pig blood and sucrose followed by blood) under laboratory conditions were observed for offspring emergence to examine the survival period expressed as the median emergence time (E50) and female fecundity (females/female). Life table was constructed including the mean life expectancy at emergence (e0) as a measure of longevity and the mortality rate per day (qx). Results: Females fed on sucrose-blood has the highest fecundity and the shortest E50 compared to those fed on other diets. The mean life expectancy at emergence (e0) differed significantly with the highest value being for females fed on sucrose. Interpretation & conclusion: The calculated expectancies for female life beyond the infective age (8 days) indicated that more flies would survive to become infective when fed on sucrose-blood meals than those offered blood alone which increases its capability for Leishmania transmission.
RESUMO
The whitefly Bemisia tuberculata has caused serious damage to cassava producing areas in the state of Mato Grosso do Sul. However, little is known about the biological characteristics of this species. The objective of this study was therefore, to monitor the development of this species bred on cassava plants under controlled greenhouse conditions, and to determine its most vulnerable stages and its reproductive capacity, as well as measuring the length and width each stage of development. To obtain these data, adult individuals were kept in voile traps on cassava leaves of five different plants, totalling ten leaves. After 24 hours the leaves were removed from the traps thus making each egg-laden leaf an experimental unit. The lowest mortality rate was record in the last nymphal stage ('pupae) compared with the other development stages. The highest mortality occurred in the nymphs at the 2nd and 3rd instars. Each female laid an average of 6.3 eggs in 24 hours. Thirteen days after egg laying, every one of the nymphs was fixed on the leaves of cassava plants. From the egg laying stage up until the adult stage, the process took 26 days. The proportion of females was 73.5%. The average size of the B. tuberculata egg was 163.22 µm in length and 72.39 µm in width and the "pupae" is 915.82 µm in length and 628.71 µm in width. The measurements of males were 797.16 µm in length and 200.81 µm in width and the length females 916.12 µm in length and 338.99 µm in width. The parasitoid Encarsia porteri (Mercet, 1928) (Hymenoptera, Aphelinidae) was found in the insect stock culture.
A mosca-branca Bemisia tuberculata tem causado sérios danos a áreas produtoras de mandioca do Estado do Mato Grosso do Sul. No entanto, pouco se sabe sobre as características biológicas dessa espécie. O objetivo deste trabalho foi, portanto, acompanhar o desenvolvimento dessa espécie criada em plantas de mandioca em condições de casa de vegetação, além de determinar as suas fases mais vulneráveis e a sua capacidade reprodutiva, e medir o comprimento e a largura das fases de desenvolvimento. Para obter esses dados, os indivíduos adultos foram mantidos em armadilhas voil de folhas de mandioca, de cinco plantas diferentes (duas folhas por planta), totalizando dez folhas. Após 24 horas, as folhas foram retiradas das armadilhas, tornando-se cada folha carregada de ovos uma unidade experimental. Na última fase de ninfa (pupa), a menor taxa de mortalidade foi observada, em comparação com os outros estágios de desenvolvimento. A maior mortalidade ocorreu em ninfas, fixadas em segundo e terceiro ínstares. Cada fêmea depositou uma média de 6,3 ovos em 24 horas. Após 13 dias de postura dos ovos, todas as ninfas estavam fixas nas folhas das plantas de mandioca. A partir da postura dos ovos até a fase de aparecimento dos adultos, foram necessários 26 dias. Houve uma proporção de 73,5% de fêmeas. Os ovos de B. tuberculata medem 163,22 µm de comprimento e 72,39 µm de largura. A pupa mede 915,82 µm de comprimento e 628,71 µm de largura. O macho mede 797,16 µm de comprimento e 200,81 µm de largura, e a fêmea mede 916,12 µm de comprimento e 338,99 µm de largura. O parasitoide Encarsia porteri (Mercet, 1928) (Hymenoptera, Aphelinidae) foi encontrado na criação estoque.
Assuntos
Animais , Feminino , Masculino , Hemípteros/fisiologia , Manihot/parasitologia , Interações Hospedeiro-Parasita , Hemípteros/classificação , Hemípteros/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Longevidade , Oviposição , Fatores de TempoRESUMO
The knowledge of population effects of food on tropical, filter-feeding cladocerans is scarce because a reduced number of species has been extensively studied. Ceriodaphnia rigaudi Richard 1894, a small-sized cladoceran distributed mainly in tropical and subtropical regions of the world, was studied. The aim of this study was to contribute to the knowledge of the reproductive biology of a poor-known Cladoceran; for this we assessed the effect of feeding and temperature on the reproduction and life cycle of this species. Three microalga species (Pseudokirchneriella subcapitata, Ankistrodesmus falcatus, and Chlorella vulgaris) were supplied as food each at a concentration of 12 mg l-1 (dry weight, equivalent to 1.3X106, 0.4X106 and 1.35X106 cell ml-1, respectively, and equivalent to 7.80 Eg C ml-1), at two temperatures (20 and 25oC). We evaluated, among other responses, longevity, total progeny, survival, life expectancy at birth and fecundity. Organisms fed with the microalgae A. falcatus and P. subcapitata presented both higher longevity (30.7± 5.91, 26.6 ± 3.59 days, respectively) and total progeny (45 ± 13.80, 40.7 ± 0.66 neonates female-1) values than those organisms fed C. vulgaris (13.5± 4.63 days and 17.6 ± 6.19 neonates female-1, respectively). On the other hand, temperature affected significantly the population parameters of C. rigaudi, recording maximal longevity values (56.1 ± 9.41 days) at 20oC in organisms fed A. falcatus; however, age at first reproduction and total progeny were negatively affected by this temperature: sexual maturation of the females was delayed until the age of 16 days and the number of neonates produced was smaller (9.8 ± 3.45 with C. vulgaris; 24.7±6.01 with P. subcapitata, and 35.5 ± 8.59 neonates female-1 with A. falcatus). The best reproductive responses for C. rigaudi in this study were obtained with A. falcatus at 25oC.