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Braz. j. biol ; 79(4): 584-588, Nov. 2019. tab
Article in English | LILACS | ID: biblio-1001478


Abstract The properties of maize pollen in the diet of Doru luteipes were determined by biological responses of the predator feeding on natural preys and artificial diet. The biological parameters of D. luteipes fed on Spodoptera frugiperda (Smith, 1797) eggs, maize pollen, Rhopalosiphum maidis (Fitch, 1856) + maize pollen and R. maidis were assessed. The effect of pollen on artificial diet on the biological variables of the predator nymphs and adults were also evaluated. Time span of nymphal development was greater for D. luteipes exclusively fed on earwigs, with the lowest rate of nymph survival. However, maize pollen plus earwigs in the diet provided the predator´s highest survival rate, whilst percentage of fertile females was double when fed on diets composed of S. frugiperda and R. maidis eggs. Development period decreased when D. luteipes nymphs consumed artificial diet plus pollen but there were high fecundity rates (number of laying/female and total egg/female) and a greater percentage of fertile females when they were fed on maize pollen.

Resumo Os benefícios do pólen de milho na composição da dieta de Doru luteipes foram determinados por meio das respostas biológicas desse predador alimentado com presas naturais e dieta artificial. Inicialmente, avaliaram-se parâmetros biológicos de D. luteipes alimentados com: ovos de Spodoptera frugiperda (Smith, 1797), pólen de milho, pólen de milho e Rhopalosiphum maidis (Fitch, 1856) e R. maidis. Posteriormente, verificou-se o efeito da presença do pólen em dieta artificial nas variáveis ​​biológicas de ninfas e adultos do predador. O período de desenvolvimento ninfal foi maior para D. luteipes alimentado, exclusivamente, com pulgões, sendo esta dieta a que propiciou menor sobrevivência ninfal. No entanto, a adição de pólen de milho na dieta com pulgões proporcionou maior taxa de sobrevivência do predador e, o percentual de fêmeas que ovipositaram foi praticamente o dobro em relação às dietas compostas por ovos de S. frugiperda e R. maidis. Quando ninfas de D. luteipes consumiram a dieta artificial adicionada com pólen verificou-se redução no período de desenvolvimento ninfal e quando o pólen de milho foi fornecido apenas na fase adulta houve uma maior fecundidade (número de posturas/fêmea e total de ovos/fêmea) e porcentagem de fêmeas que ovipositaram.

Animals , Female , Pollen , Zea mays , Food Chain , Insecta/physiology , Brazil , Diet , Insecta/growth & development , Nymph/growth & development , Nymph/physiology
Braz. j. biol ; 77(4): 703-709, Nov. 2017. tab
Article in English | LILACS | ID: biblio-888815


Abstract The purpose of this study was to investigate the development and reproduction of the zoophytophagous predator Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) fed kale, broccoli and cabbage affects its. Nymphs and adults of this predator were fed on larvae of Plutella xylostella (L.) (Lepidoptera: Plutellidae) as prey with kale, cabbage, or broccoli. In the nymph period, the duration and prey consumption were similar with all the Brassicacea cultivar. However, nymph viability was higher for predators with broccoli leaves. The mean weight of 5th-instar nymphs, newly emerged females and the sex ratio were similar among the Brassicacea cultivars, while newly emerged males were heavier with kale and broccoli leaves. The supply of broccoli leaves resulted in greater oviposition, higher number of eggs per egg mass and longer longevity of P. nigrispinus males and females. Furthermore, the consumption of P. xylostella larvae by adult predators was higher with these cultivars. The net reproductive rate (R0) and mean generation time (T) were highest for predators with prey and broccoli leaves. The reproductive parameters of P. nigrispinus were enhanced when fed on P. xylostella larvae with and broccoli leaves, which can be an alternative diet in laboratory rearing of this predator.

Resumo O objetivo deste estudo foi verificar o desenvolvimento e reprodução do zoofitófago Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) em couve, brócolis e repolho. Ninfas e adultos deste predador foram alimentados com lagartas de Plutella xylostella (L.) (Lepidoptera: Plutellidae) como presa e receberam folhas de couve, repolho ou brócolis. Durante o período ninfal, a duração do período e o consumo de presas foram semelhantes com as diferentes cultivares de brassicácea. Porém, a viabilidade ninfal foi maior para predadores com folhas de brócolis. O peso de ninfas de quinto instar e de fêmeas recém-emergidas e a razão sexual de P. nigrispinus foram semelhantes entre as cultivares de brassicáceas, enquanto que o peso de machos recém-emergidos foi maior com folhas de couve e brócolis. Folhas de brócolis proporcionaram maiores número de oviposições, ovos por postura e longevidade de machos e fêmeas de P. nigrispinus. Além disso, o consumo de lagartas de P. xylostella por adultos desse predador fora maiores com esta cultivar. A taxa líquida de reprodução (R0) e o tempo médio de geração (T) foram maiores para predadores com presa e folhas de brócolis. Podisus nigrispinus alimentados com lagartas de P. xylostella e folhas de brócolis apresentaram melhores parâmetros reprodutivos, podendo ser uma alternativa para a criação deste predador em laboratório.

Animals , Male , Female , Predatory Behavior , Brassicaceae/chemistry , Heteroptera/physiology , Moths/chemistry , Nymph/physiology , Heteroptera/growth & development , Food Chain , Larva/growth & development , Larva/chemistry , Moths/growth & development , Nymph/growth & development
Braz. j. biol ; 77(2): 267-276, Apr.-June 2017. tab, graf
Article in English | LILACS | ID: biblio-888742


Abstract Sexual choice by male stink bugs is important because females that experience food shortages lay fewer eggs with lower viability compared with well-fed females. In this study, we investigated whether Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) males fed with a low-quality diet during its nymphal stage show selectivity for sexual partners resulting in high-quality progeny. Lightweight males and females were obtained from nymphs fed weekly with Tenebrio molitor L. (Coleoptera: Tenebrionidae) pupae. By contrast, heavyweight males and females were fed three times a week and received an extra nutritional source: cotton leaves, Gossypium hirsutum L. (Malvaceae). Lightweight males preferred to mate with heavy females (77.78 ± 14.69%), whereas heavyweight males did not discriminated between light or heavyweight females. Females mated with lightweight males showed similar levels of reproduction to those mated with heavyweight males. The results provide an indication of the importance of male and female body weight for sexual selection in Asopinae stink bugs.

Resumo A seleção sexual por machos de percevejos é importante porque fêmeas que passaram por escassez alimentar poem poucos ovos com baixa viabilidade em comparação com fêmeas bem alimentadas. Nesse estudo, investigamos se machos de Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) alimentados com dieta de baixa qualidade durante seu estágio ninfal apresenta seletividade por parceiras sexuais resultando em progênie de alta qualidade. Machos e fêmeas leves foram obtidos de ninfas alimentadas semanalmente com pupas de Tenebrio molitor L. (Coleoptera: Tenebrionidae). Em contraste, machos e fêmeas pesados foram alimentados três vezes por semana e receberam uma fonte nutricional extra: folhas de algodão, Gossypium hirsutum L. (Malvaceae). Machos leves preferiram acasalar com fêmeas pesadas (77,78 ± 14,69%), enquanto machos pesados não distinguiram fêmeas leves ou pesadas para acasalamento. Fêmeas que acasalaram com machos leves apresentaram níveis de reprodução semelhantes em comparação com aquelas acasaladas com machos pesados. Os resultados fornecem uma indicação da importância do peso corpóreo de machos e fêmeas para a seleção sexual em percevejos Asopinae.

Animals , Male , Female , Body Weight , Heteroptera/physiology , Genetic Fitness , Reproduction , Heteroptera/growth & development , Heteroptera/genetics , Diet , Nymph/growth & development , Nymph/physiology , Nymph/genetics
Braz. j. biol ; 76(4): 937-941, Oct.-Dec. 2016. tab
Article in English | LILACS | ID: biblio-828102


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.

Animals , Female , Aphids/growth & development , Fragaria , Reproduction , Life Tables , Fertility , Longevity , Nymph/growth & development
Braz. j. biol ; 75(4,supl.1): 158-162, Nov. 2015. tab, graf
Article in English | LILACS | ID: lil-768228


Abstract Nasonovia ribisnigri is a key pest of lettuce (Lactuca sativa L.) in Brazil that requires alternative control methods to synthetic pesticides. We report, for the first time, the occurrence of Paecilomyces niveus as an entomopathogen of the aphid Nasonovia ribisnigri in Pinhais, Paraná, Brazil. Samples of mummified aphids were collected from lettuce crops. The fungus P. niveus (PaePR) was isolated from the insect bodies and identified by macro and micromorphology. The species was confirmed by sequencing Internal Transcribed Spacer (ITS) rDNA. We obtained a sequence of 528 bp (accession number HQ441751), which aligned with Byssochlamys nivea strains (100% identities). In a bioassay, 120 h after inoculation of N. ribisnigri with pathogenic P. niveus had an average mortality of 74%. The presence of P. niveus as a natural pathogen of N. ribisnigri in Brazil suggests that it may be possible to employ P. niveus to minimize the use of chemical insecticides.

Resumo Nasonovia ribisnigri é uma praga-chave do cultivo de alface (Lactuca sativa L.), exigindo métodos alternativos ao controle químico. Este trabalho registrou pela primeira vez, a ocorrência de Paecilomyces niveus como agente entomopatogenico do afídeo N. ribisnigri em Pinhais, Paraná, Brasil. Amostras de afídeos mumificados foram coletadas em plantas de alface. O fungo P. niveus (PaePR) foi isolado do corpo dos insetos e identificado por macro e micromorfologia e, confirmado por sequenciamento da região ITS do DNA ribossomal. A sequencia parcial de 528 bp (número de acesso HQ441751) apresentou alinhamento com 100% de identidade com sequencias de raças de Byssochlamys nivea. No bioensaio de patogenicidade P. niveus apresentou uma mortalidade média de N. ribisnigri de 74% até 120 horas da inoculação. O registro da presença de P. niveus como um patógeno natural de N. ribisnigri no Brasil sugere o potencial de utilização para minimizar o uso de inseticidas.

Animals , Aphids/microbiology , Paecilomyces/physiology , Aphids/growth & development , Brazil , Byssochlamys/classification , Byssochlamys/isolation & purification , Byssochlamys/physiology , DNA, Fungal , Molecular Sequence Data , Nymph/growth & development , Nymph/microbiology , Paecilomyces/classification , Paecilomyces/isolation & purification , Sequence Analysis, DNA
Rev. biol. trop ; 62(supl.2): 41-51, abr. 2014. ilus, graf, tab
Article in English | LILACS | ID: lil-753755


Interspecific interactions can play an important role in determining habitat selection and resource use between competing species. We examined interactions between an omnivorous shrimp and a grazing mayfly, two co-dominant taxa found in Puerto Rican headwater streams, to assess how predator presence may influence mayfly resource use and instantaneous growth in a tropical rainforest ecosystem. We conducted a series of behavioral and growth experiments to determine the effects of the freshwater shrimp, Xiphocaris elongata, on the growth rate and resource selection of mayfly nymphs in the family Leptophlebiidae. For resource choice assessments, we conducted a series of five day laboratory experiments where mayflies were given access to two resource substrate choices (cobble vs. leaves) in the presence or absence of shrimp. To assess for the effects of shrimp on mayfly fitness, we measured mayfly growth in laboratory aquaria after five days using four treatments (cobble, leaves, cobble + leaves, no resource) in the presence or absence of shrimp. In resource choice experiments, mayflies showed preference for cobble over leaf substrata (p<0.05) regardless of the presence of shrimps, however, the preference for cobble was significantly greater when shrimp were present in the leaf habitat. In growth experiments, there were no statistical differences in mayfly growth in the presence or absence of shrimp (p=0.07). However, we measured increased mayfly nymph growth in the absence of predators and when both cobble and leaves were available. Our results suggest that interspecific interactions between these taxa could potentially influence organic matter resource dynamics (e.g., leaf litter processing and export) in Puerto Rican streams. Rev. Biol. Trop. 62 (Suppl. 2): 41-51. Epub 2014 April 01.

Las relaciones interespecíficas pueden jugar un papel importante en la determinación del uso de recursos y selección de hábitat entre especies que compiten. Hemos examinado las interacciones entre un camarón omnívoro y un efemeróptero que se alimenta de vegetación , dos taxones codominantes en las partes altas de arroyos de Puerto Rico, para evaluar el efecto de los depredadores en el uso de recursos del efemeróptero y el crecimiento instantáneo en un ecosistema de selva tropical. Examinamos experimentalmente el efecto del camarón Xiphocaris elongata sobre la tasa de crecimiento y selección de recursos en ninfas efemerópteras (Leptophlebiidae). Hicimos experimentos de laboratorio de 5 días, dando a los efemerópteros acceso a dos opciones de sustrato (piedrecillas u hojas) en presencia o ausencia del camarón. Para evaluar los efectos sobre el crecimiento probamos cuatro tratamientos (piedrecillas, hojas , piedrecillas + hojas, sin ambas), en presencia o ausencia del camarón. Los efemerópteros prefirieron las piedrecillas a las hojas ( p < 0,05 ) independientemente de la presencia de los camarones. Esta preferencia fue mayor cuando junto a las hojas había camarones. Los camarones no afectaron el crecimiento de los efemerópteros (p = 0,07). Las ninfas efemerópteras crecieron mejor sin camarones y en acuarios con piedrecillas y hojas. Nuestros resultados sugieren que las interacciones interespecíficas entre estos animales podrían influir en la dinámica de la materia orgánica (por ejemplo, procesamiento de la hojarasca y su exportación) en los arroyos puertoriqueños.

Animals , Decapoda/physiology , Ecosystem , Insecta/physiology , Nymph/growth & development , Decapoda/classification , Food Preferences , Insecta/classification , Life Cycle Stages , Nymph/classification , Puerto Rico
Journal of Veterinary Science ; : 421-424, 2013.
Article in English | WPRIM | ID: wpr-43066


An adult male rufous turtle dove, Streptopelia (S.) orientalis (Aves: Columbiformes), was found dead in Yorii-machi Town, Osato District 369-1217, Saitama Prefecture, Japan, and subjected to necropsy. A large number of immobile hypopi (deutonymphs) of the hypoderatid mite, Hypodectes (H.) propus (Acarina: Hypoderatidae), were found individually encapsulated subcutaneously primarily in the adipose tissue. The mites were 1.43 mm in length and 0.44 mm in width on average, and had provoked mild inflammatory reactions that predominantly manifested as foamy macrophages and lymphoplasmocytes. PCR analysis using ribosomal DNA extracted from paraffin-blocked tissues produced a 240 bp band specific for hypoderatids. Based on the morphological features (distinct coxal apodemes, especially in the anterior portion) and PCR-based findings, the hypopi were identified as H. propus. To the best of our knowledge, this is the first case describing the subcutaneous mite H. propus in a rufous turtle dove, S. orientalis, in Japan. This study also highlights the use of paraffin blocks as a source of tissue DNA for molecular evaluation.

Animals , Male , Bird Diseases/diagnosis , Columbidae/parasitology , DNA, Ribosomal/genetics , Formaldehyde/metabolism , Japan , Mite Infestations/diagnosis , Mites/growth & development , Nymph/growth & development , Paraffin Embedding/veterinary , Polymerase Chain Reaction/veterinary
Biol. Res ; 44(1): 69-74, 2011. ilus, tab
Article in English | LILACS | ID: lil-591866


Respiration and energy metabolism are key processes in animals, which are severely constrained by the design of physical structures, such as respiratory structures. Insects have very particular respiratory systems, based on gas diffusion across tracheae. Since the efficiency of the tracheal respiratory system is highly dependent on body shape, the pattern of morphological variation during ontogeny could have important metabolic consequences. We studied this problem combining through-flow respirometry and geometric morphometrics in 88 nymphs of the sand cricket, Gryllus firmus. After measuring production in each individual, we took digital photographs and defined eight landmarks for geometric morphometric analysis. The analysis suggested that ontogenic deformations were mostly related to enlargement of the abdomen, compared to thorax and head. We found that (controlling for body size) metabolic variables and especially resting metabolism are positively correlated with a shape-component associated to an elongation of the abdomen. Our results are in agreement with the mechanics of tracheal ventilation in orthopterans, as gas circulation occurs by changes in abdominal pressures due to abdominal contractions and expansions along the longitudinal axis.

Animals , Female , Male , Energy Metabolism/physiology , Gryllidae/anatomy & histology , Gryllidae/metabolism , Respiratory Physiological Phenomena , Calorimetry, Indirect , Gryllidae/growth & development , Nymph/anatomy & histology , Nymph/growth & development , Nymph/metabolism
Mem. Inst. Oswaldo Cruz ; 105(8): 1057-1060, Dec. 2010. graf
Article in English | LILACS | ID: lil-570680


The aim of this work was to study the interaction between Trypanosoma cruzi-1 and Triatoma brasiliensis. A group of 1st instar nymphs was initially fed on T. cruzi-infected mice and a control group was fed on uninfected mice. From the second feeding onwards, both groups were otherwise fed on non-infected mice. The resulting adults were grouped in pairs: infected male/uninfected female, uninfected male/infected female, infected male and female and uninfected male/uninfected female. The infection affected only the 1st instar nymphs, which took significantly more time to reach the 2nd instar than uninfected nymphs. The differences in the molting time between the infected and uninfected nymphs from the 2nd to the 5th instars were not statistically significant. Both groups presented similar rates of nymphal mortality and reproductive performance was not significantly affected by infection in any of the treatments.

Animals , Female , Male , Mice , Molting/physiology , Triatoma/growth & development , Trypanosoma cruzi/physiology , Nymph/growth & development , Reproduction/physiology , Triatoma , Triatoma/physiology
Rev. bras. parasitol. vet ; 19(3): 164-168, July-Sept. 2010. tab
Article in English | LILACS | ID: lil-604662


The current study investigated the biology of nymphs of the first and second instars of Argas (Persicargas) miniatus. Nymphs were deprived of food for 15, 30 or 60 days and held at 27 ± 1 ºC and 80 ± 10 percent relative humidity (controlled conditions) or at room conditions of temperature and relative humidity. Nymphs of first instar deprived of food for 15 or 30 days molted to second and third instars in both controlled and room conditions. Nymphs of the first instar deprived of food for 60 days had 28 and 37 percent mortality in controlled and room conditions, respectively; and survivors did not attach to the host. Nymphs of the second instar, deprived of food for 60 days, molted either to the third instar or to males after feeding on Gallus gallus, and the nymphs of the third instar developed to adults (42.42 percent males and 36.36 percent females when nymphs were held in controlled temperature and humidity conditions, and 40.54 percent males and 48.65 percent females when nymphs were held in room conditions). The remainder of the nymphs molted to the fourth instar and then molted to females. In conclusion, the nymphal starvation period of 60 days determined the number of nymph instars in the life cycle of A. miniatus under the experimental conditions studied.

Os aspectos biológicos de ninfas de primeiro e segundo instares de Argas (Persicargas) miniatus quando submetidas a diferentes períodos de jejum (15, 30 e 60 dias), foram estudados em estufa climatizada (27 ± 1 ºC e 80 ± 10 por cento de umidade relativa) e em ambiente de laboratório. Ninfas de primeiro instar que foram submetidas a um período de jejum de 15 e 30 dias mudaram para ninfas de segundo e terceiro instar, em ambas as condições estudadas. No período de 60 dias de jejum verificou-se mortalidade de 28 e 37 por cento das ninfas de primeiro instar, em estufa climatizada e em ambiente de laboratório, respectivamente. As ninfas sobreviventes não se fixaram sobre os hospedeiros. As ninfas de segundo instar, após 60 dias de jejum, desenvolveram-se em ninfas de terceiro instar ou machos, quando alimentadas em Gallus gallus. Ainda neste grupo, as ninfas de terceiro instar mudaram para adultos (42,42 e 40,54 por cento machos; 36,36 e 48,65 por cento fêmeas, nas condições ambiente de laboratório e estufa climatizada, respectivamente) e o restante desenvolveu-se em ninfas de quarto instar que por sua vez mudaram para fêmeas. Então, a situação de jejum (60 dias) em que as ninfas foram submetidas determinou o número de ninfas no ciclo biológico de A. miniatus, sob as condições experimentais estudadas.

Animals , Female , Male , Argas/growth & development , Fasting , Nymph/growth & development , Sex Factors , Time Factors
Mem. Inst. Oswaldo Cruz ; 104(4): 668-670, July 2009. mapas, tab
Article in English | LILACS | ID: lil-523740


Strategies for controlling Chagas disease are based on spraying infested houses with pyrethroid insecticides. However, the intense use of these insecticides has promoted resistance of Triatoma infestans and, in Argentina, Bolivia and Southern Brazil, low levels of resistance have been reported. Due to the persistence of T. infestans in the state of Rio Grande do Sul (RS), we evaluated the occurrence of deltamethrin resistance in four strains from different municipalities in comparison to two susceptible strains from Brazil and one resistant strain from Bolivia. The results indicated the absence of resistance in T. infestans from RS.

Animals , Insecticides , Nitriles , Pyrethrins , Triatoma , Bolivia , Brazil , Insecticide Resistance , Nymph/drug effects , Nymph/growth & development
Mem. Inst. Oswaldo Cruz ; 103(8): 839-842, Dec. 2008. tab
Article in English | LILACS | ID: lil-502307


Studies were carried out to evaluate the efficacy of the growth regulator, triflumuron (TFM) (Starycide® sc 480 Bayer), for disrupting the development of Rhodnius prolixus fifth-instar nymph by oral, topical or continuous treatment. All treatments were able to induce high levels of mortality, delay development and molt inhibition. Oral treatment induced molt inhibition in all insects that survived at doses of 0.25, 0.50 and 5.0 mg/mL of a blood meal. The highest levels of both mortality in 24 h and molt inhibition were always observed after topical treatment. The lowest doses needed to obtain considerable biological effects were always observed after continuous treatment. In this way, the highest levels of mortality within 30 days were detected after continuous treatment, which also induced an extended inter-molting period, a lower number of over-aged nymphs and the highest level of molting in nymphs that survived. Moreover, the effects of TFM on insects were often displayed in a dose response manner. These results indicate that TFM acts as a potent growth inhibitor of R. prolixus nymphs and has the potential to be used in integrated vector control programs against hematophagous triatomine species.

Animals , Male , Benzamides/pharmacology , Insecticides/pharmacology , Rhodnius/drug effects , Dose-Response Relationship, Drug , Nymph/drug effects , Nymph/growth & development , Rhodnius/growth & development , Time Factors
Neotrop. entomol ; 37(4): 353-360, July-Aug. 2008. graf, tab
Article in English | LILACS | ID: lil-492694


The biology of the pentatomid Dichelops melacanthus (Dallas) feeding on cultivated and non-cultivated plants was studied in the laboratory. Nymph mortality varied from ≈ 60 on corn (seed mature) to 77 percent on wheat (ear immature); no nymphs survived on seedlings of corn or wheat. Nymph developmental time on soybean, corn or wheat (seed, pod or ear) varied from 25.5 to 32.8 days. Body weight at adult emergence was similar and greater on most foods than on wheat ear. Nymphs fed preferentially on soybean (pod immature). On non-cultivated hosts, nymphs showed high mortality (73 percent) on crotalaria (pod immature); on tropical spiderwort (stem) all nymphs died. Nymphs took longer time to develop on crotalaria and/or on spiderwort than on soybean. Body weight at adult emergence did not differ on crotalaria or soybean. Survivorship decreased with time on most foods, with ≈50 percent of adults alive at day 30. On corn and wheat seedlings ≈80 percent of adults were dead on day 20. Adult longevity ranged 31-43 days, except on corn and wheat seedlings < 15 days. Females percent ovipositing peaked (≈76 percent) on soybean (pod or seed immature), and was minimum (≈9 percent) on wheat ear (immature); no females reproduced on seedlings of corn or wheat. Preoviposition period was shorter (≈12 days) on soybean (immature pod or seed) and longer (≈37 days) on wheat (ear immature). Fecundity was similar and higher on all foods than on wheat (ear immature). Body weigh gain occurred on all foods, but on corn and wheat seedlings. Adults fed preferably on soybean (pod immature and seed mature); wheat (seedling) was the least preferred food.

A biologia do pentatomídeo Dichelops melacanthus (Dallas) em plantas cultivadas e não-cultivadas foi estudada em laboratório. A mortalidade ninfal variou de ≈ 60 por cento em milho (semente madura) a 77 por cento em trigo (espiga imatura); nenhuma ninfa sobreviveu em plântulas de milho ou trigo. O desenvolvimento ninfal em soja, milho ou trigo (semente, vagem ou espiga) variou de 25,5 a 32,8 dias. O peso dos adultos na emergência foi menor em espiga de trigo. As ninfas alimentaram-se preferencialmente de soja (vagem imatura). Nas plantas não-cultivadas, as ninfas tiveram mortalidade de 73 por cento em crotalária (vagem imatura); e 100 por cento em trapoeraba (ramo). O desenvolvimento ninfal foi mais lento em crotalária ou trapoeraba do que em soja. A sobrevivência dos adultos decresceu com o tempo na maioria dos alimentos, com ≈50 por cento dos adultos vivos no 30º dia. Em plântulas de milho e trigo ≈80 por cento dos adultos estavam mortos no 20º dia. A longevidade total dos adultos variou de 31-43 dias, exceto em plântulas de milho e trigo (< 15 dias). A por cento de fêmeas que ovipositou foi maior (≈76 por cento) em soja (vagem ou semente imatura) e menor (≈9 por cento) em espiga imatura de trigo; as fêmeas não reproduziram em plântulas de milho ou trigo. O período de pré-oviposição foi menor (≈12 dias) em soja (vagem ou semente imatura) e maior (≈37 dias) em trigo (espiga imatura). A fecundidade foi semelhante e maior em todos os alimentos do que em trigo (espiga imatura). O ganho de peso ocorreu em todos os alimentos, menos plântulas de milho e trigo. Os adultos alimentaram-se preferencialmente em soja (vagem imatura e semente madura); plântula de trigo foi o alimento menos preferido.

Animals , Female , Heteroptera/growth & development , Soybeans/parasitology , Triticum/parasitology , Zea mays/parasitology , Body Weight , Fertility/physiology , Heteroptera/anatomy & histology , Longevity , Nymph/growth & development , Oviposition/physiology
Rev. bras. entomol ; 51(4): 484-488, out.-dez. 2007. graf, tab
Article in English | LILACS | ID: lil-473170


The biology of nymphs and adults of the neotropical pentatomid, Dichelops melacanthus (Dallas), feeding on the natural foods, soybean, Glycine max (L.) Merrill immature pods, and corn, Zea mays L. immature seeds, and on an artificial dry diet, was studied in the laboratory. Nymph developmental time was shorter on the natural foods (ca. 21-22 days) than on the artificial diet (28 days), and most nymphs reached adulthood on the food plants (55 percent on soybean and 73 percent on corn) than on the artificial diet (40 percent). Fresh body weight at adult emergence was similar and higher for females raised as nymphs on the natural foods, compared to females from nymphs raised on the artificial diet; for males, weights were similar on all foods. Mean (female and male) survivorship up to day 20, decreased from 55 percent on soybean to 40 percent on corn, down to 0 percent on the artificial diet. Total longevity for females was higher on soybean, while for males was similar on all foods. About three times more females oviposited on soybean than on corn, but fecundity/female was similar on both foods. On the artificial diet, only one out of 30 females oviposited. Fresh body weight of adults increased significantly during the first week of adult life, and at the end of the 3rd week, weight gain was similar on all foods.

A biologia de ninfas e de adultos do pentatomídeo neotropical Dichelops melacanthus (Dallas), alimentando-se de vagens imaturas de soja, Glycine max (L.) Merrill e sementes imaturas de milho, Zea mays L., e de dieta artificial seca, foi estudada em laboratório. O tempo de desenvolvimento ninfal foi menor nas dietas naturais (ca. 21-22 dias) do que na dieta artificial (28 dias), e a maioria das ninfas atingiram a fase adulta nas dietas naturais (55 por cento em soja e 73 por cento em milho) o que não ocorreu na dieta artificial (40 por cento). O peso fresco dos adultos na emergência foi semelhante e maior para as fêmeas criadas como ninfas nas dietas naturais, comparado às fêmeas cujas ninfas foram criadas na dieta artificial; para os machos, os pesos foram semelhantes em todos os alimentos. A sobrevivência média de fêmeas e machos no 20º dia decresceu de 55 por cento em soja para 40 por cento em milho, e para 0 por cento na dieta artificial. A longevidade total para fêmeas foi maior em soja, enquanto para machos foi semelhante em todos os alimentos. Cerca de três vêzes mais fêmeas ovipositaram em soja do que em milho, mas a fecundidade/fêmea foi semelhante em ambos os alimentos. Na dieta artificial, de 30 fêmeas, apenas uma ovipositou. O ganho de peso fresco de adultos aumentou significativamente na primeira semana de vida adulta; no final da 3ª semana, o ganho de peso foi semelhante em todos os alimentos.

Animals , Male , Female , Biology , Diet , Heteroptera/growth & development , Heteroptera/physiology , Longevity , Weight Gain , Nymph/growth & development , Nymph/physiology
Rev. Soc. Bras. Med. Trop ; 40(4): 443-446, jul.-ago. 2007. tab
Article in Portuguese | LILACS, SES-SP | ID: lil-460252


Os autores analisaram em condições de laboratório, a taxa de sobrevida das ninfas, duração mínima e máxima de cada estádio, tempo de vida das formas adultas e postura das fêmeas. Foram acompanhados dois grupos de 100 ovos. Lote A, exemplares criados em um único cristalizador. Lote B os exemplares foram mantidos isolados um a um e ao atingir a fase alada formaram 20 casais, possibilitando o controle da postura das fêmeas e o tempo de vida de cada exemplar. O percentual de eclosão dos ovos foi de 96 por cento; a taxa de vida no final da fase ninfal foi de 69,5 por cento no Lote A e de 78,4 por cento no Lote B. A maior freqüência observada no tempo decorrido entre postura e eclosão da ninfa do 1° estádio foi de 28 dias. O tempo de permanência na fase de ninfa foi de 4 a 8 meses e de 5 meses na fase adulta. A postura total (média) no Lote B foi de 181,6 ovos por fêmea.

Under laboratory conditions, the authors analyzed the survival rate of nymphs, the minimum and maximum duration of each stage, the length of life of the winged forms and oviposition of the females. Two groups of 100 eggs each were monitored. In batch A, the specimens were reared in a single glass receptacle. In batch B, the specimens were kept apart, one by one, and when they reached the winged stage, they formed twenty couples, which made it possible to watch over the oviposition of the females and the length of life of each specimen. The egg eclosion rate was 96 percent; the proportion still alive at the end of the nymph phase was 69. 5 percent in batch A and 78. 4 percent in batch B. The most frequent length of time observed between oviposition and eclosion of first-stage nymphs was 28 days. The nymph phase lasted four to eight months and the adult phase five months. The mean total oviposition in batch B was 181. 6 eggs per female.

Animals , Female , Male , Oviposition/physiology , Triatoma/physiology , Laboratories , Life Cycle Stages , Life Tables , Nymph/growth & development , Triatoma/anatomy & histology
Parasitol. latinoam ; 61(1/2): 17-22, jun. 2006. ilus
Article in Spanish | LILACS | ID: lil-432844


En este trabajo se determinó cualitativa y cuantitativamente la composición química de un extracto en benceno de ejemplares de Rhodnius prolixus en diferentes estadios ninfales y edades reproductivas de las hembras. El análisis fue realizado mediante técnicas uni- y bidimensionales (1D y 2D) de Resonancia Magnética Nuclear (RMN). Se han clasificado los compuestos químicos presentes en el extracto como A, B y C, según sus zonas de desplazamiento químico. El compuesto A, situado en la zona entre d 5,0 y 5,33 ppm, puede ser atribuido a hidrógenos olefínicos (alquenos) y está presente en todo los estadios ninfales y edades reproductivas, por lo que no es de utilidad para ser marcador de edades. El Compuesto C, situado en la zona entre 2,5 ppm y 3,5 ppm, representa distintas señales las cuales presumiblemente según sus desplazamientos químicos corresponden a hidrógenos sobre carbonos nitrogenados y sirve como marcador de edad para diferenciar entre los estadios ninfales y el comienzo de la edad adulta. El Compuesto B, presente en la zona entre 4 y 5 ppm, corresponde a un triacilglicerol, y es un marcador importante para diferenciar entre las hembras no ovipositoras (HNO) y ovipositoras (HO), ya que esta última edad carece de este compuesto. También es útil usar la relación de concentraciones de los compuestos A y B, que viene dada por la integral de la señal para determinar la diferencia de edades entre los estadios ninfales. Se proponen estas técnicas para determinar los estadios ninfales y las edades reproductivas de las hembras en una muestra de triatominos colectados en condiciones de campo, lo que revelaría información importante para conocer algunas de las variables de las que depende la capacidad vectora de estos insectos en la transmisión de la Enfermedad de Chagas.

Animals , Female , Life Cycle Stages , Magnetic Resonance Spectroscopy , Rhodnius/growth & development , Rhodnius/chemistry , Benzene , Chagas Disease , Insect Vectors/chemistry , Biomarkers , Nuclear Magnetic Resonance, Biomolecular , Nymph/growth & development , Nymph/chemistry
Rev. ciênc. farm. básica apl ; 27(2): 157-161, 2006. tab
Article in Portuguese | LILACS | ID: lil-466196


A partir de ninfas de 5o estádio obtiveram-se casais de Rhodnius prolixus, que originaram ovos e ninfas para estudos de ciclo biológico e biométrico. Foram determinados os seguintes parâmetros do ciclo biológico à temperatura de 28OC e umidade relativa do ar variando entre 52 e 94%: período médio de incubação dos ovos: 13,01 dias; taxa de eclosão dos ovos: 77,6%; período médio de desenvolvimento do 1º, 2º, 3º, 4º e 5º estádio ninfal: 19, 33;19,09; 20,38; 24,37; 38,14 dias, respectivamente;percentual de mortes nos estádios ninfais: 26,70; 14,00;18,26; 17,02; 35,47% respectivamente; percentual de mudas por estádio ninfal; 73,30; 86,03; 81,73; 82,97 e 64,52%, respectivamente. Estudo biométrico mostrou que o abdômen é o maior segmento em todos os estádios. Nos quatro primeiros estádios a cabeça apresenta-se maior que o tórax, enquanto no quinto estádio a cabeça e o tórax apresentam portes equivalentes.

Animals , Biometry/methods , Nymph/growth & development , Ovum/growth & development , Rhodnius/growth & development , Triatominae
Rev. Soc. Bras. Med. Trop ; 38(3): 251-254, maio-jun. 2005. tab
Article in Portuguese | LILACS, SES-SP | ID: lil-399918


Os autores acompanharam a evolução de 150 ovos de Triatoma rubrovaria o que permitiu a construção de uma tábua de sobrevida das ninfas. A forma alada foi atingida por 94,64 por cento dos exemplares, sendo 79 deles machos e 65 fêmeas. O tempo médio dos alados machos foi de 115 dias e das fêmeas, 99 dias. Parte desses exemplares formaram 30 casais, mantidos isolados, o que possibilitou o levantamento da postura de cada fêmea. Outro lote, também formado por 30 machos e 30 fêmeas, foi mantido em um único cristalizador de vidro, o que permitiu constatar sua maior postura (7.832 ovos) em relação aquela das fêmeas acasaladas por único macho (5.167). O bom desenvolvimento dos exemplares no processo de evolução e de reprodução da espécie, nas condições do experimento, mostrou a boa capacidade de manutenção das colônias do Triatoma rubrovaria, em condições de laboratório.

Animals , Male , Female , Life Tables , Oviposition/physiology , Triatoma/physiology , Life Cycle Stages , Nymph/growth & development , Triatoma/anatomy & histology
Biocell ; 28(3): 259-269, dic. 2004. ilus
Article in English | LILACS | ID: lil-405198


The post-embryonic development of the female gonads in Triatoma infestans (Hemiptera, Heteroptera), insects of importance in health affairs as harbors and vectors of different tripanosomatidea flagellates, is presented in a complete follow-up since insect hatches from the egg up to the last molt in the fifth instar stage. The detailed description of the morphological changes which occur in each instar as well as careful measurements evaluating its size increase have been analyzed by stereomicroscopy, phase contrast, dark field, and oblique ilumination, in order to optimize the observations as well the photographic register of gonad morphology and structure. The analysis was performed on gonad specimens obtained from broods no less than twenty (20) nymph bugs, reared at constant temperature and fed-up regularly. According to the results of our study we can assert that gonad differentiation takes place in early phases of the insect development. Such is tge case that first instars nymph´s present absolutely and easily recognizably male and female gonads. From the third instar on beside the filament region, the three zones in each ovariole body is distinguished, a differentiation that is more noticeable during the fourth instar where a definite organization is present at the vitelarium. Such a clear cut zone development continues intensively during the fifth instar. Finally at the end of such fifth nymph stage and when the last molt toward adults is prepared, clear signs of ovariole maturation take place since oocytes in early vitelogenesis are found.

Animals , Female , Dogs , Morphogenesis , Nymph/anatomy & histology , Nymph/cytology , Ovary/anatomy & histology , Ovary/cytology , Triatoma/anatomy & histology , Triatoma/cytology , Gonads/anatomy & histology , Gonads/cytology , Gonads/growth & development , Nymph/growth & development , Ovary/growth & development , Triatoma/growth & development
Rev. cuba. med. trop ; 50(2): 143-149, Mayo-ago. 1998.
Article in Spanish | LILACS | ID: lil-629292


Se realizó un estudio con 2 colonias de Blattella germanica (Dictyoptera:Blattellidae), mantenidas desde 1994 en el laboratorio a 29± 1ºC, 70-75 % de humedad relativa y con alimentos diferentes: una con una dieta carente de proteínas, consistente en porciones de papa (Solanum tuberosum, L.), plátano maduro (Musa paradisiaca, L.) y solución azucarada al 10 %, y la otra con un contenido preoteico de 20,45 % que consistió en alimento de laboratorio para rata, pulverizado y seco, y una fuente de agua. Se encontraron 6 estadios ninfales con ambos tipos de alimentos y se determinaron, en cada caso, los tiempos intermudas y el tiempo de desarrollo ninfal, éstos resultaron mucho más cortos en las ninfas alimentadas con proteínas. La longevidad de cada sexo no mostró diferencias significativas en relación con el tipo de alimento utilizado. Se determinaron los tiempos en que aparecen y eclosionan las ootecas de cada ciclo ootecal con ambos alimentos. Se encontró que las hembras depositaron hasta 5 ootecas durante su vida con los 2 tipos de dietas, el promedio de ninfas por ooteca en las hembras alimentadas con proteínas fue mucho mayor (t=5,33; p<=0,001). Los resultados de este estudio demuestran que cuando el alimento de B. germanica contiene proteínas, su desarrollo ninfal es más rápido y aumenta su capacidad reproductiva, lo que lo hace un nutriente necesario en la dieta de esta especie.

It was conducted a study of 2 colonies of Blattella germanica (Dictyoptera: Blattellidae) kept since 1994 in he laboratory at 29 ± 1º C, 70-75 % of relative humidity and with different foods: one on a diet without proteins, consisitging in portions of potatoes (Solanum tuberosum, L.), ripe banana (Musa paradisiaca, L.) and a sugary solution 10 %, and the other with a protein content of 20.45 % composed of pulverized and dry laboratory food for rats and a source of water. 6 nymphal stages were found with both types of food. There were determined the times of interchanges and the time of nymphal development, which were much shorter among the nymphs feeded with proteins. The longevity of each sex showed no significant differences in connection with the type of food used. The times of appearance and eclosion of the oothecae of each oothecal cycle were determined with both foods. It was found that the females deposited up to 5 oothecae during their lives with the 2 types of diet. The average of nymphs per ootheca among the females feeded with proteins was much greater (t= 5,33; p < 0,001). The results of this study show that when the food for B. germanica contains proteins, its nymphal development is faster and its reproductive capacity increases, which means that protein is a necessary nutrient for the diet of this species.

Animals , Female , Male , Cockroaches/physiology , Diet/veterinary , Analysis of Variance , Breeding , Dietary Proteins/administration & dosage , Feeding Behavior/physiology , Longevity , Nymph/growth & development , Reproduction