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Differential susceptibility of adults and nymphs of Blattella germanica (L.) (Blattodea: Blattellidae) to infection by Metarhizium anisopliae and assessment of delivery strategies
Lopes, RB;Alves, SB;
Neotropical Entomology , 2011, DOI: 10.1590/S1519-566X2011000300010
Abstract: microbial insecticides for cockroach control, such as those containing entomopathogenic fungi, may be an alternative to reduce contamination by chemicals in housing and food storage environments. virulence of isolate esalq1037 belonging to the metarhizium anisopliae complex against nymphs and adults of blattella germanica (l.), and its infectivity following exposure of insects to a contaminated surface or to m. anisopliae-bait were determined under laboratory conditions. estimated ld50 15 d following topical inoculation was 2.69 x 105 conidia per adult, whereas for nymphs the maximum mortality was lower than 50%. baits amended with m. anisopliae conidia had no repellent effect on targets; adult mortality was inferior to 25%, and nymphs were not susceptible. all conidia found in the digestive tract of m. anisopliae-bait fed cockroaches were unviable, and bait-treated insects that succumbed to fungal infection showed a typical mycelial growth on mouthparts and front legs, but not on the hind body parts. as opposed to baits, the use of a m. anisopliae powdery formulation for surface treatment was effective in attaining high mortality rates of b. germanica. both nymphs and adults were infected when this delivery strategy was used, and mycelia growth occurred all over the body surface. our results suggest that the development of powders or similar formulations of m. anisopliae to control b. germanica may provide faster and better results than some of the strategies based on baits currently available.
Actividad biológica del diflubenzuron sobre Blattella germanica (Dictyoptera: Blattellidae)
. Lucita Aguilera,María del C. Marquetti,Agustín Navarro
Revista Cubana de Medicina Tropical , 2001,
Abstract: Se realizó un estudio con la cepa Ameijeiras de Blattella germanica (Dictyoptera: Blattellidae), mantenida en el laboratorio desde el a o 1994 y susceptible a los insecticidas propoxur, malation y cipermetrina. Esta cepa fue tratada con 4 concentraciones diferentes de diflubenzuron (Dimilin, OMS 1804), suministradas a través del alimento a ninfas de primer estadio de desarrollo, con el objetivo de determinar su efecto sobre la supervivencia, el fenotipo y el período de desarrollo ninfal de esta especie. Se determinó la línea de regresión dosis-mortalidad y se obtuvieron los valores de CE50 = 0,042 % y CE95 = 0,357 %. Se observaron efectos subletales en las ninfas tratadas con las 4 concentraciones probadas, mientras que los efectos morfogenéticos en los adultos solo aparecieron en los que fueron expuestos a las concentraciones más altas (0,25 y 0,4 %). El período de desarrollo ninfal mostró un incremento altamente significativo al aumentar la concentración del inhibidor (F = 11,64; p The Ameijeiras strain of Blatella germanica (Dictyoptera: Blattellidae) kept in lab conditions since 1994 and susceptible to arpocarb, malathion and cipermethrin insecticides, was studied. This strain was treated with 4 diflubenzuron (Dimilin OMS 1804) concentrations supplied by feeding nymphs at their first stage of development, with the purpose of determining their effect on the survival, phenotype and period of nynmphal development of this species. The dosage-mortality line of regression was determined and the values of CE50= 0.042% and CE95= 0.357% were obtained. Sublethal effects were observed in the nymphs treated with the 4 tested concentrations whereas the morphogenetic effects in adult insects only occured when they were exposed to higher concentrations (0.25% and 0.4%). The nymph development stage showed a highly significant increase when the diflubenzuron concentration was raised. (F=11.64; p
Actividad biológica del diflubenzuron sobre Blattella germanica (Dictyoptera: Blattellidae)
Aguilera,. Lucita; Marquetti,María del C.; Navarro,Agustín;
Revista Cubana de Medicina Tropical , 2001,
Abstract: the ameijeiras strain of blatella germanica (dictyoptera: blattellidae) kept in lab conditions since 1994 and susceptible to arpocarb, malathion and cipermethrin insecticides, was studied. this strain was treated with 4 diflubenzuron (dimilin oms 1804) concentrations supplied by feeding nymphs at their first stage of development, with the purpose of determining their effect on the survival, phenotype and period of nynmphal development of this species. the dosage-mortality line of regression was determined and the values of ce50= 0.042% and ce95= 0.357% were obtained. sublethal effects were observed in the nymphs treated with the 4 tested concentrations whereas the morphogenetic effects in adult insects only occured when they were exposed to higher concentrations (0.25% and 0.4%). the nymph development stage showed a highly significant increase when the diflubenzuron concentration was raised. (f=11.64; p
Observaciones sobre aspectos biológicos de Blattella germanica (Dictyoptera: Blattellidae) en condiciones de laboratorio
AGUILERA,LUCITA; MARQUETTI,MARIA C; FUENTES,OMAR; NAVARRO,AGUSTIN;
Revista Cubana de Medicina Tropical , 1996,
Abstract: se realizó un estudio de blattella germanica (l.) 1767 (dictyoptera: blattellidae) en condiciones de laboratorio, se encontraron 6 estadios ninfales en un período de 114,71 días, a 29 ± 1oc y de 80 a 90 % de humedad relativa. se determinaron los tiempos de aparición y eclosión de cada ooteca puesta, así como el promedio de descendientes de cada una. las hembras depositaron hasta 5 ootecas a lo largo de su vida, el promedio máximo de nuevos encontrado por ooteca fue de 29,22. la longevidad promedio de los machos fue menor que la de las hembras (77,23 y 98,40 días, respectivamente) (t = 2,21; p < 0,05).
Observaciones sobre aspectos biológicos de Blattella germanica (Dictyoptera: Blattellidae) en condiciones de laboratorio  [cached]
LUCITA AGUILERA,MARIA C MARQUETTI,OMAR FUENTES,AGUSTIN NAVARRO
Revista Cubana de Medicina Tropical , 1996,
Abstract: Se realizó un estudio de Blattella germanica (L.) 1767 (Dictyoptera: Blattellidae) en condiciones de laboratorio, se encontraron 6 estadios ninfales en un período de 114,71 días, a 29 ± 1oC y de 80 a 90 % de humedad relativa. Se determinaron los tiempos de aparición y eclosión de cada ooteca puesta, así como el promedio de descendientes de cada una. Las hembras depositaron hasta 5 ootecas a lo largo de su vida, el promedio máximo de nuevos encontrado por ooteca fue de 29,22. La longevidad promedio de los machos fue menor que la de las hembras (77,23 y 98,40 días, respectivamente) (t = 2,21; p < 0,05).
Susceptibility of Field Populations of Blattella germanica (Blattaria: Blattellidae) to Spinosad  [PDF]
H. Nasiria,H. Ladonni,M. Aboulhassani,M. Limoee
Pakistan Journal of Biological Sciences , 2011,
Abstract: The German cockroach is an important household insect pest worldwide and acts as a mechanical vector and reservoir for pathogenic agents. The aim of this study was to examine the basic laboratory toxicity of Blattella germanica to spinosad. The M, T, A22, AZAR4, BOOSTAN7 and ABAN21 strains were collected from field populations of six infested kitchen student dormitories and the SAMAN strain was collected from a residential area after insecticide spraying control failure in Tehran, Iran. Technical grade spinosad was delivered in 0.5 L acetone to the first abdominal sternum of briefly CO2-anesthetize adult male cockroaches by topical application bioassay. Treated males monitored for mortality. Mortality data from the replicates was assessed by probit analysis. The average LD50 of susceptible strain was 494.3, 148.8 and 55.1 ng per insect after 24, 48 and 72 h, respectively. The LD50 of spinosad decreased with time in the field population strains. All German cockroach strains showed a similar susceptibility or lower tolerance (1.6-folds) for spinosad compared with the susceptible laboratory strain and the steep slopes of dose-response curves indicated that the field population of these German cockroach strains was homogenous in response to spinosad. These results indicated that the spinosad was relatively slow-acting in topical application bioassay, with LD50 values decreasing until 72 h and becoming stable thereafter. The effectiveness of spinosad against susceptible and the field population German cockroach strains in laboratory condition showed that spinosad probably could be useful for the control of the German cockroach.
Determinación de la resistencia a insecticidas y mecanismos de resistencia en cepas de Blattella germanica (Dictyoptera: Blattellidae) Determination of insecticide-resistance and resistance mechanisms of Blattella germanica (Dictyoptera: Blattellidae)
Cristina Díaz Pantoja,Yudelmis álvarez Gavilán,Yaxsier de Armas Rodríguez,Juan A. Bisset Lazcano
Revista Cubana de Medicina Tropical , 2007,
Abstract: Se evaluaron los niveles de resistencia en 3 cepas de Blattella germanica colectadas en diferentes lugares de Ciudad de La Habana, frente a 4 insecticidas. Las cepas fueron resistentes a los 2 piretroides evaluados (cipermetrina y lambdacialotrina) y al organofosforado malatión, mostrándose susceptibles ante el carbamato propoxur. Se determinaron los valores de α y β Esterasas, acetilcolinesterasa y glutation S-transferasa, a ejemplares de las 3 cepas involucradas en el estudio. Los resultados del trabajo mostraron una elevada actividad de esterasas en todas las cepas, sobre todo de las β Esterasas, en 2 de las 3 cepas estudiadas la enzima glutation S-transferasa fue elevada y no se demostrσ que existan modificaciones en la acetilcolinesterasa en relaciσn con la cepa de referencia. La relaciσn entre los niveles de resistencia a insecticidas, los posibles mecanismos de resistencia presentes en cada cepa y los resultados de la actividad enzimática, fueron analizados. In this paper, the level of resistance to four insecticides of 3 Blatella germanica strains collected from various places in the City of Havana province was evaluated. These strains were resistant to two pyrethroids (cypermethrin and lambdacyalothrine) and to organophosphorate malathion but susceptible to carbamate propoxur. The values of α and β esterases, acetylcholinesterase and gluthatione-S-transferase were estimated in three strains involved in the study. The results of the study showed high esterase activity in all the strains, mainly β esterases and two of the three strains presented with high gluthation-S-transferase enzyme. No changes in acetylcholinesterase were demonstrated in relation to the reference strain. The association of levels of resistance to insecticides, the possible resistance mechanisms in each strain and the results of the enzymatic activity were also analyzed.
Efecto de 2 dietas sobre aspectos biológicos de Blattella germanica (Dictyoptera: Blattellidae) en condiciones de laboratorio
Aguilera,Lucita; Marquetti,María del Carmen; Fuentes,Omar; Navarro,Agustín;
Revista Cubana de Medicina Tropical , 1998,
Abstract: 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.
Toxicity of Pyrethroid and Organophosphorous Insecticides against Two Field Collected Strains of the German Cockroach Blattella germanica (Blattaria: Blattellidae) from Hospitals in Hamadan, Iran  [cached]
Mojtaba Limoee,Behroz Davari,Seyed Hassan Moosa-Kazemi
Journal of Arthropod-Borne Diseases , 2012,
Abstract: Background: The German cockroach, Blattella germanica is a major hygienic pest and mechanical vector for pathogenicagents in hospitals and residential areas. The development of insecticide resistance is a serious problem incontrolling of this pest. Toxicity of four commonly used insecticides (permethrin, cypermethrin, malathion andchlorpyrifos) against two hospital- collected strains of the German cockroach was investigated.Methods: Topical bioassay methods were carried out for detecting insecticide susceptibility of adult male cockroaches.For each insecticide, four to six concentrations resulting in >0% and <100% mortality were used. Three tosix replicates of 10 cockroaches per concentration were conducted. The differences between LD50 (μg/g) values wereconsidered statistically significant only when the 95% confidence intervals did not overlap.Results: Two hospital- collected strains of the German cockroach showed low to moderate levels of resistance tochlorpyrifos, permethrin, malathion and cypermethrin based on resistance ratios compared with susceptible strain.Conclusion: The low level chlorpyrifos resistance suggesting this insecticide may still provide adequate control ofthese strains. While the obsereved moderate levels of resistance to cypermethrin could imply developing resistanceto this compound.
Efecto de 2 dietas sobre aspectos biológicos de Blattella germanica (Dictyoptera: Blattellidae) en condiciones de laboratorio
Lucita Aguilera,María del Carmen Marquetti,Omar Fuentes,Agustín Navarro
Revista Cubana de Medicina Tropical , 1998,
Abstract: 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 nym
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